cw1200: When debug is enabled, display all wakeup conditions for the wait_event_inter...
[firefly-linux-kernel-4.4.55.git] / include / net / neighbour.h
1 #ifndef _NET_NEIGHBOUR_H
2 #define _NET_NEIGHBOUR_H
3
4 #include <linux/neighbour.h>
5
6 /*
7  *      Generic neighbour manipulation
8  *
9  *      Authors:
10  *      Pedro Roque             <roque@di.fc.ul.pt>
11  *      Alexey Kuznetsov        <kuznet@ms2.inr.ac.ru>
12  *
13  *      Changes:
14  *
15  *      Harald Welte:           <laforge@gnumonks.org>
16  *              - Add neighbour cache statistics like rtstat
17  */
18
19 #include <linux/atomic.h>
20 #include <linux/netdevice.h>
21 #include <linux/skbuff.h>
22 #include <linux/rcupdate.h>
23 #include <linux/seq_file.h>
24
25 #include <linux/err.h>
26 #include <linux/sysctl.h>
27 #include <linux/workqueue.h>
28 #include <net/rtnetlink.h>
29
30 /*
31  * NUD stands for "neighbor unreachability detection"
32  */
33
34 #define NUD_IN_TIMER    (NUD_INCOMPLETE|NUD_REACHABLE|NUD_DELAY|NUD_PROBE)
35 #define NUD_VALID       (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
36 #define NUD_CONNECTED   (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)
37
38 struct neighbour;
39
40 struct neigh_parms {
41 #ifdef CONFIG_NET_NS
42         struct net *net;
43 #endif
44         struct net_device *dev;
45         struct neigh_parms *next;
46         int     (*neigh_setup)(struct neighbour *);
47         void    (*neigh_cleanup)(struct neighbour *);
48         struct neigh_table *tbl;
49
50         void    *sysctl_table;
51
52         int dead;
53         atomic_t refcnt;
54         struct rcu_head rcu_head;
55
56         int     base_reachable_time;
57         int     retrans_time;
58         int     gc_staletime;
59         int     reachable_time;
60         int     delay_probe_time;
61
62         int     queue_len_bytes;
63         int     ucast_probes;
64         int     app_probes;
65         int     mcast_probes;
66         int     anycast_delay;
67         int     proxy_delay;
68         int     proxy_qlen;
69         int     locktime;
70 };
71
72 struct neigh_statistics {
73         unsigned long allocs;           /* number of allocated neighs */
74         unsigned long destroys;         /* number of destroyed neighs */
75         unsigned long hash_grows;       /* number of hash resizes */
76
77         unsigned long res_failed;       /* number of failed resolutions */
78
79         unsigned long lookups;          /* number of lookups */
80         unsigned long hits;             /* number of hits (among lookups) */
81
82         unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */
83         unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
84
85         unsigned long periodic_gc_runs; /* number of periodic GC runs */
86         unsigned long forced_gc_runs;   /* number of forced GC runs */
87
88         unsigned long unres_discards;   /* number of unresolved drops */
89 };
90
91 #define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
92
93 struct neighbour {
94         struct neighbour __rcu  *next;
95         struct neigh_table      *tbl;
96         struct neigh_parms      *parms;
97         unsigned long           confirmed;
98         unsigned long           updated;
99         rwlock_t                lock;
100         atomic_t                refcnt;
101         struct sk_buff_head     arp_queue;
102         unsigned int            arp_queue_len_bytes;
103         struct timer_list       timer;
104         unsigned long           used;
105         atomic_t                probes;
106         __u8                    flags;
107         __u8                    nud_state;
108         __u8                    type;
109         __u8                    dead;
110         seqlock_t               ha_lock;
111         unsigned char           ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
112         struct hh_cache         hh;
113         int                     (*output)(struct neighbour *, struct sk_buff *);
114         const struct neigh_ops  *ops;
115         struct rcu_head         rcu;
116         struct net_device       *dev;
117         u8                      primary_key[0];
118 };
119
120 struct neigh_ops {
121         int                     family;
122         void                    (*solicit)(struct neighbour *, struct sk_buff *);
123         void                    (*error_report)(struct neighbour *, struct sk_buff *);
124         int                     (*output)(struct neighbour *, struct sk_buff *);
125         int                     (*connected_output)(struct neighbour *, struct sk_buff *);
126 };
127
128 struct pneigh_entry {
129         struct pneigh_entry     *next;
130 #ifdef CONFIG_NET_NS
131         struct net              *net;
132 #endif
133         struct net_device       *dev;
134         u8                      flags;
135         u8                      key[0];
136 };
137
138 /*
139  *      neighbour table manipulation
140  */
141
142 #define NEIGH_NUM_HASH_RND      4
143
144 struct neigh_hash_table {
145         struct neighbour __rcu  **hash_buckets;
146         unsigned int            hash_shift;
147         __u32                   hash_rnd[NEIGH_NUM_HASH_RND];
148         struct rcu_head         rcu;
149 };
150
151
152 struct neigh_table {
153         struct neigh_table      *next;
154         int                     family;
155         int                     entry_size;
156         int                     key_len;
157         __u32                   (*hash)(const void *pkey,
158                                         const struct net_device *dev,
159                                         __u32 *hash_rnd);
160         int                     (*constructor)(struct neighbour *);
161         int                     (*pconstructor)(struct pneigh_entry *);
162         void                    (*pdestructor)(struct pneigh_entry *);
163         void                    (*proxy_redo)(struct sk_buff *skb);
164         char                    *id;
165         struct neigh_parms      parms;
166         /* HACK. gc_* should follow parms without a gap! */
167         int                     gc_interval;
168         int                     gc_thresh1;
169         int                     gc_thresh2;
170         int                     gc_thresh3;
171         unsigned long           last_flush;
172         struct delayed_work     gc_work;
173         struct timer_list       proxy_timer;
174         struct sk_buff_head     proxy_queue;
175         atomic_t                entries;
176         rwlock_t                lock;
177         unsigned long           last_rand;
178         struct neigh_statistics __percpu *stats;
179         struct neigh_hash_table __rcu *nht;
180         struct pneigh_entry     **phash_buckets;
181 };
182
183 #define NEIGH_PRIV_ALIGN        sizeof(long long)
184 #define NEIGH_ENTRY_SIZE(size)  ALIGN((size), NEIGH_PRIV_ALIGN)
185
186 static inline void *neighbour_priv(const struct neighbour *n)
187 {
188         return (char *)n + n->tbl->entry_size;
189 }
190
191 /* flags for neigh_update() */
192 #define NEIGH_UPDATE_F_OVERRIDE                 0x00000001
193 #define NEIGH_UPDATE_F_WEAK_OVERRIDE            0x00000002
194 #define NEIGH_UPDATE_F_OVERRIDE_ISROUTER        0x00000004
195 #define NEIGH_UPDATE_F_ISROUTER                 0x40000000
196 #define NEIGH_UPDATE_F_ADMIN                    0x80000000
197
198 extern void                     neigh_table_init(struct neigh_table *tbl);
199 extern int                      neigh_table_clear(struct neigh_table *tbl);
200 extern struct neighbour *       neigh_lookup(struct neigh_table *tbl,
201                                              const void *pkey,
202                                              struct net_device *dev);
203 extern struct neighbour *       neigh_lookup_nodev(struct neigh_table *tbl,
204                                                    struct net *net,
205                                                    const void *pkey);
206 extern struct neighbour *       __neigh_create(struct neigh_table *tbl,
207                                                const void *pkey,
208                                                struct net_device *dev,
209                                                bool want_ref);
210 static inline struct neighbour *neigh_create(struct neigh_table *tbl,
211                                              const void *pkey,
212                                              struct net_device *dev)
213 {
214         return __neigh_create(tbl, pkey, dev, true);
215 }
216 extern void                     neigh_destroy(struct neighbour *neigh);
217 extern int                      __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
218 extern int                      neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, 
219                                              u32 flags);
220 extern void                     neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
221 extern int                      neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
222 extern int                      neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
223 extern int                      neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
224 extern int                      neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb);
225 extern int                      neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
226 extern struct neighbour         *neigh_event_ns(struct neigh_table *tbl,
227                                                 u8 *lladdr, void *saddr,
228                                                 struct net_device *dev);
229
230 extern struct neigh_parms       *neigh_parms_alloc(struct net_device *dev, struct neigh_table *tbl);
231 extern void                     neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
232
233 static inline
234 struct net                      *neigh_parms_net(const struct neigh_parms *parms)
235 {
236         return read_pnet(&parms->net);
237 }
238
239 extern unsigned long            neigh_rand_reach_time(unsigned long base);
240
241 extern void                     pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
242                                                struct sk_buff *skb);
243 extern struct pneigh_entry      *pneigh_lookup(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev, int creat);
244 extern struct pneigh_entry      *__pneigh_lookup(struct neigh_table *tbl,
245                                                  struct net *net,
246                                                  const void *key,
247                                                  struct net_device *dev);
248 extern int                      pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev);
249
250 static inline
251 struct net                      *pneigh_net(const struct pneigh_entry *pneigh)
252 {
253         return read_pnet(&pneigh->net);
254 }
255
256 extern void neigh_app_ns(struct neighbour *n);
257 extern void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie);
258 extern void __neigh_for_each_release(struct neigh_table *tbl, int (*cb)(struct neighbour *));
259 extern void pneigh_for_each(struct neigh_table *tbl, void (*cb)(struct pneigh_entry *));
260
261 struct neigh_seq_state {
262         struct seq_net_private p;
263         struct neigh_table *tbl;
264         struct neigh_hash_table *nht;
265         void *(*neigh_sub_iter)(struct neigh_seq_state *state,
266                                 struct neighbour *n, loff_t *pos);
267         unsigned int bucket;
268         unsigned int flags;
269 #define NEIGH_SEQ_NEIGH_ONLY    0x00000001
270 #define NEIGH_SEQ_IS_PNEIGH     0x00000002
271 #define NEIGH_SEQ_SKIP_NOARP    0x00000004
272 };
273 extern void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *, unsigned int);
274 extern void *neigh_seq_next(struct seq_file *, void *, loff_t *);
275 extern void neigh_seq_stop(struct seq_file *, void *);
276
277 extern int                      neigh_sysctl_register(struct net_device *dev, 
278                                                       struct neigh_parms *p,
279                                                       char *p_name,
280                                                       proc_handler *proc_handler);
281 extern void                     neigh_sysctl_unregister(struct neigh_parms *p);
282
283 static inline void __neigh_parms_put(struct neigh_parms *parms)
284 {
285         atomic_dec(&parms->refcnt);
286 }
287
288 static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
289 {
290         atomic_inc(&parms->refcnt);
291         return parms;
292 }
293
294 /*
295  *      Neighbour references
296  */
297
298 static inline void neigh_release(struct neighbour *neigh)
299 {
300         if (atomic_dec_and_test(&neigh->refcnt))
301                 neigh_destroy(neigh);
302 }
303
304 static inline struct neighbour * neigh_clone(struct neighbour *neigh)
305 {
306         if (neigh)
307                 atomic_inc(&neigh->refcnt);
308         return neigh;
309 }
310
311 #define neigh_hold(n)   atomic_inc(&(n)->refcnt)
312
313 static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
314 {
315         unsigned long now = jiffies;
316         
317         if (neigh->used != now)
318                 neigh->used = now;
319         if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
320                 return __neigh_event_send(neigh, skb);
321         return 0;
322 }
323
324 #ifdef CONFIG_BRIDGE_NETFILTER
325 static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
326 {
327         unsigned int seq, hh_alen;
328
329         do {
330                 seq = read_seqbegin(&hh->hh_lock);
331                 hh_alen = HH_DATA_ALIGN(ETH_HLEN);
332                 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
333         } while (read_seqretry(&hh->hh_lock, seq));
334         return 0;
335 }
336 #endif
337
338 static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
339 {
340         unsigned int seq;
341         int hh_len;
342
343         do {
344                 seq = read_seqbegin(&hh->hh_lock);
345                 hh_len = hh->hh_len;
346                 if (likely(hh_len <= HH_DATA_MOD)) {
347                         /* this is inlined by gcc */
348                         memcpy(skb->data - HH_DATA_MOD, hh->hh_data, HH_DATA_MOD);
349                 } else {
350                         int hh_alen = HH_DATA_ALIGN(hh_len);
351
352                         memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
353                 }
354         } while (read_seqretry(&hh->hh_lock, seq));
355
356         skb_push(skb, hh_len);
357         return dev_queue_xmit(skb);
358 }
359
360 static inline struct neighbour *
361 __neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
362 {
363         struct neighbour *n = neigh_lookup(tbl, pkey, dev);
364
365         if (n || !creat)
366                 return n;
367
368         n = neigh_create(tbl, pkey, dev);
369         return IS_ERR(n) ? NULL : n;
370 }
371
372 static inline struct neighbour *
373 __neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
374   struct net_device *dev)
375 {
376         struct neighbour *n = neigh_lookup(tbl, pkey, dev);
377
378         if (n)
379                 return n;
380
381         return neigh_create(tbl, pkey, dev);
382 }
383
384 struct neighbour_cb {
385         unsigned long sched_next;
386         unsigned int flags;
387 };
388
389 #define LOCALLY_ENQUEUED 0x1
390
391 #define NEIGH_CB(skb)   ((struct neighbour_cb *)(skb)->cb)
392
393 static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
394                                      const struct net_device *dev)
395 {
396         unsigned int seq;
397
398         do {
399                 seq = read_seqbegin(&n->ha_lock);
400                 memcpy(dst, n->ha, dev->addr_len);
401         } while (read_seqretry(&n->ha_lock, seq));
402 }
403 #endif