Merge tag 'armsoc-dt' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
[linux-2.6-microblaze.git] / net / batman-adv / bat_v.c
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2013-2020  B.A.T.M.A.N. contributors:
3  *
4  * Linus Lüssing, Marek Lindner
5  */
6
7 #include "bat_v.h"
8 #include "main.h"
9
10 #include <linux/atomic.h>
11 #include <linux/cache.h>
12 #include <linux/errno.h>
13 #include <linux/if_ether.h>
14 #include <linux/init.h>
15 #include <linux/jiffies.h>
16 #include <linux/kernel.h>
17 #include <linux/kref.h>
18 #include <linux/list.h>
19 #include <linux/netdevice.h>
20 #include <linux/netlink.h>
21 #include <linux/rculist.h>
22 #include <linux/rcupdate.h>
23 #include <linux/seq_file.h>
24 #include <linux/skbuff.h>
25 #include <linux/spinlock.h>
26 #include <linux/stddef.h>
27 #include <linux/types.h>
28 #include <linux/workqueue.h>
29 #include <net/genetlink.h>
30 #include <net/netlink.h>
31 #include <uapi/linux/batadv_packet.h>
32 #include <uapi/linux/batman_adv.h>
33
34 #include "bat_algo.h"
35 #include "bat_v_elp.h"
36 #include "bat_v_ogm.h"
37 #include "gateway_client.h"
38 #include "gateway_common.h"
39 #include "hard-interface.h"
40 #include "hash.h"
41 #include "log.h"
42 #include "netlink.h"
43 #include "originator.h"
44
45 static void batadv_v_iface_activate(struct batadv_hard_iface *hard_iface)
46 {
47         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
48         struct batadv_hard_iface *primary_if;
49
50         primary_if = batadv_primary_if_get_selected(bat_priv);
51
52         if (primary_if) {
53                 batadv_v_elp_iface_activate(primary_if, hard_iface);
54                 batadv_hardif_put(primary_if);
55         }
56
57         /* B.A.T.M.A.N. V does not use any queuing mechanism, therefore it can
58          * set the interface as ACTIVE right away, without any risk of race
59          * condition
60          */
61         if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
62                 hard_iface->if_status = BATADV_IF_ACTIVE;
63 }
64
65 static int batadv_v_iface_enable(struct batadv_hard_iface *hard_iface)
66 {
67         int ret;
68
69         ret = batadv_v_elp_iface_enable(hard_iface);
70         if (ret < 0)
71                 return ret;
72
73         ret = batadv_v_ogm_iface_enable(hard_iface);
74         if (ret < 0)
75                 batadv_v_elp_iface_disable(hard_iface);
76
77         return ret;
78 }
79
80 static void batadv_v_iface_disable(struct batadv_hard_iface *hard_iface)
81 {
82         batadv_v_ogm_iface_disable(hard_iface);
83         batadv_v_elp_iface_disable(hard_iface);
84 }
85
86 static void batadv_v_primary_iface_set(struct batadv_hard_iface *hard_iface)
87 {
88         batadv_v_elp_primary_iface_set(hard_iface);
89         batadv_v_ogm_primary_iface_set(hard_iface);
90 }
91
92 /**
93  * batadv_v_iface_update_mac() - react to hard-interface MAC address change
94  * @hard_iface: the modified interface
95  *
96  * If the modified interface is the primary one, update the originator
97  * address in the ELP and OGM messages to reflect the new MAC address.
98  */
99 static void batadv_v_iface_update_mac(struct batadv_hard_iface *hard_iface)
100 {
101         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
102         struct batadv_hard_iface *primary_if;
103
104         primary_if = batadv_primary_if_get_selected(bat_priv);
105         if (primary_if != hard_iface)
106                 goto out;
107
108         batadv_v_primary_iface_set(hard_iface);
109 out:
110         if (primary_if)
111                 batadv_hardif_put(primary_if);
112 }
113
114 static void
115 batadv_v_hardif_neigh_init(struct batadv_hardif_neigh_node *hardif_neigh)
116 {
117         ewma_throughput_init(&hardif_neigh->bat_v.throughput);
118         INIT_WORK(&hardif_neigh->bat_v.metric_work,
119                   batadv_v_elp_throughput_metric_update);
120 }
121
122 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
123 /**
124  * batadv_v_orig_print_neigh() - print neighbors for the originator table
125  * @orig_node: the orig_node for which the neighbors are printed
126  * @if_outgoing: outgoing interface for these entries
127  * @seq: debugfs table seq_file struct
128  *
129  * Must be called while holding an rcu lock.
130  */
131 static void
132 batadv_v_orig_print_neigh(struct batadv_orig_node *orig_node,
133                           struct batadv_hard_iface *if_outgoing,
134                           struct seq_file *seq)
135 {
136         struct batadv_neigh_node *neigh_node;
137         struct batadv_neigh_ifinfo *n_ifinfo;
138
139         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
140                 n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
141                 if (!n_ifinfo)
142                         continue;
143
144                 seq_printf(seq, " %pM (%9u.%1u)",
145                            neigh_node->addr,
146                            n_ifinfo->bat_v.throughput / 10,
147                            n_ifinfo->bat_v.throughput % 10);
148
149                 batadv_neigh_ifinfo_put(n_ifinfo);
150         }
151 }
152
153 /**
154  * batadv_v_hardif_neigh_print() - print a single ELP neighbour node
155  * @seq: neighbour table seq_file struct
156  * @hardif_neigh: hardif neighbour information
157  */
158 static void
159 batadv_v_hardif_neigh_print(struct seq_file *seq,
160                             struct batadv_hardif_neigh_node *hardif_neigh)
161 {
162         int last_secs, last_msecs;
163         u32 throughput;
164
165         last_secs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) / 1000;
166         last_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) % 1000;
167         throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput);
168
169         seq_printf(seq, "%pM %4i.%03is (%9u.%1u) [%10s]\n",
170                    hardif_neigh->addr, last_secs, last_msecs, throughput / 10,
171                    throughput % 10, hardif_neigh->if_incoming->net_dev->name);
172 }
173
174 /**
175  * batadv_v_neigh_print() - print the single hop neighbour list
176  * @bat_priv: the bat priv with all the soft interface information
177  * @seq: neighbour table seq_file struct
178  */
179 static void batadv_v_neigh_print(struct batadv_priv *bat_priv,
180                                  struct seq_file *seq)
181 {
182         struct net_device *net_dev = (struct net_device *)seq->private;
183         struct batadv_hardif_neigh_node *hardif_neigh;
184         struct batadv_hard_iface *hard_iface;
185         int batman_count = 0;
186
187         seq_puts(seq,
188                  "  Neighbor        last-seen ( throughput) [        IF]\n");
189
190         rcu_read_lock();
191         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
192                 if (hard_iface->soft_iface != net_dev)
193                         continue;
194
195                 hlist_for_each_entry_rcu(hardif_neigh,
196                                          &hard_iface->neigh_list, list) {
197                         batadv_v_hardif_neigh_print(seq, hardif_neigh);
198                         batman_count++;
199                 }
200         }
201         rcu_read_unlock();
202
203         if (batman_count == 0)
204                 seq_puts(seq, "No batman nodes in range ...\n");
205 }
206 #endif
207
208 /**
209  * batadv_v_neigh_dump_neigh() - Dump a neighbour into a message
210  * @msg: Netlink message to dump into
211  * @portid: Port making netlink request
212  * @seq: Sequence number of netlink message
213  * @hardif_neigh: Neighbour to dump
214  *
215  * Return: Error code, or 0 on success
216  */
217 static int
218 batadv_v_neigh_dump_neigh(struct sk_buff *msg, u32 portid, u32 seq,
219                           struct batadv_hardif_neigh_node *hardif_neigh)
220 {
221         void *hdr;
222         unsigned int last_seen_msecs;
223         u32 throughput;
224
225         last_seen_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen);
226         throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput);
227         throughput = throughput * 100;
228
229         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
230                           BATADV_CMD_GET_NEIGHBORS);
231         if (!hdr)
232                 return -ENOBUFS;
233
234         if (nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
235                     hardif_neigh->addr) ||
236             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
237                         hardif_neigh->if_incoming->net_dev->ifindex) ||
238             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
239                         last_seen_msecs) ||
240             nla_put_u32(msg, BATADV_ATTR_THROUGHPUT, throughput))
241                 goto nla_put_failure;
242
243         genlmsg_end(msg, hdr);
244         return 0;
245
246  nla_put_failure:
247         genlmsg_cancel(msg, hdr);
248         return -EMSGSIZE;
249 }
250
251 /**
252  * batadv_v_neigh_dump_hardif() - Dump the  neighbours of a hard interface into
253  *  a message
254  * @msg: Netlink message to dump into
255  * @portid: Port making netlink request
256  * @seq: Sequence number of netlink message
257  * @bat_priv: The bat priv with all the soft interface information
258  * @hard_iface: The hard interface to be dumped
259  * @idx_s: Entries to be skipped
260  *
261  * This function assumes the caller holds rcu_read_lock().
262  *
263  * Return: Error code, or 0 on success
264  */
265 static int
266 batadv_v_neigh_dump_hardif(struct sk_buff *msg, u32 portid, u32 seq,
267                            struct batadv_priv *bat_priv,
268                            struct batadv_hard_iface *hard_iface,
269                            int *idx_s)
270 {
271         struct batadv_hardif_neigh_node *hardif_neigh;
272         int idx = 0;
273
274         hlist_for_each_entry_rcu(hardif_neigh,
275                                  &hard_iface->neigh_list, list) {
276                 if (idx++ < *idx_s)
277                         continue;
278
279                 if (batadv_v_neigh_dump_neigh(msg, portid, seq, hardif_neigh)) {
280                         *idx_s = idx - 1;
281                         return -EMSGSIZE;
282                 }
283         }
284
285         *idx_s = 0;
286         return 0;
287 }
288
289 /**
290  * batadv_v_neigh_dump() - Dump the neighbours of a hard interface  into a
291  *  message
292  * @msg: Netlink message to dump into
293  * @cb: Control block containing additional options
294  * @bat_priv: The bat priv with all the soft interface information
295  * @single_hardif: Limit dumping to this hard interface
296  */
297 static void
298 batadv_v_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb,
299                     struct batadv_priv *bat_priv,
300                     struct batadv_hard_iface *single_hardif)
301 {
302         struct batadv_hard_iface *hard_iface;
303         int i_hardif = 0;
304         int i_hardif_s = cb->args[0];
305         int idx = cb->args[1];
306         int portid = NETLINK_CB(cb->skb).portid;
307
308         rcu_read_lock();
309         if (single_hardif) {
310                 if (i_hardif_s == 0) {
311                         if (batadv_v_neigh_dump_hardif(msg, portid,
312                                                        cb->nlh->nlmsg_seq,
313                                                        bat_priv, single_hardif,
314                                                        &idx) == 0)
315                                 i_hardif++;
316                 }
317         } else {
318                 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
319                         if (hard_iface->soft_iface != bat_priv->soft_iface)
320                                 continue;
321
322                         if (i_hardif++ < i_hardif_s)
323                                 continue;
324
325                         if (batadv_v_neigh_dump_hardif(msg, portid,
326                                                        cb->nlh->nlmsg_seq,
327                                                        bat_priv, hard_iface,
328                                                        &idx)) {
329                                 i_hardif--;
330                                 break;
331                         }
332                 }
333         }
334         rcu_read_unlock();
335
336         cb->args[0] = i_hardif;
337         cb->args[1] = idx;
338 }
339
340 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
341 /**
342  * batadv_v_orig_print() - print the originator table
343  * @bat_priv: the bat priv with all the soft interface information
344  * @seq: debugfs table seq_file struct
345  * @if_outgoing: the outgoing interface for which this should be printed
346  */
347 static void batadv_v_orig_print(struct batadv_priv *bat_priv,
348                                 struct seq_file *seq,
349                                 struct batadv_hard_iface *if_outgoing)
350 {
351         struct batadv_neigh_node *neigh_node;
352         struct batadv_hashtable *hash = bat_priv->orig_hash;
353         int last_seen_msecs, last_seen_secs;
354         struct batadv_orig_node *orig_node;
355         struct batadv_neigh_ifinfo *n_ifinfo;
356         unsigned long last_seen_jiffies;
357         struct hlist_head *head;
358         int batman_count = 0;
359         u32 i;
360
361         seq_puts(seq,
362                  "  Originator      last-seen ( throughput)           Nexthop [outgoingIF]:   Potential nexthops ...\n");
363
364         for (i = 0; i < hash->size; i++) {
365                 head = &hash->table[i];
366
367                 rcu_read_lock();
368                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
369                         neigh_node = batadv_orig_router_get(orig_node,
370                                                             if_outgoing);
371                         if (!neigh_node)
372                                 continue;
373
374                         n_ifinfo = batadv_neigh_ifinfo_get(neigh_node,
375                                                            if_outgoing);
376                         if (!n_ifinfo)
377                                 goto next;
378
379                         last_seen_jiffies = jiffies - orig_node->last_seen;
380                         last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
381                         last_seen_secs = last_seen_msecs / 1000;
382                         last_seen_msecs = last_seen_msecs % 1000;
383
384                         seq_printf(seq, "%pM %4i.%03is (%9u.%1u) %pM [%10s]:",
385                                    orig_node->orig, last_seen_secs,
386                                    last_seen_msecs,
387                                    n_ifinfo->bat_v.throughput / 10,
388                                    n_ifinfo->bat_v.throughput % 10,
389                                    neigh_node->addr,
390                                    neigh_node->if_incoming->net_dev->name);
391
392                         batadv_v_orig_print_neigh(orig_node, if_outgoing, seq);
393                         seq_putc(seq, '\n');
394                         batman_count++;
395
396 next:
397                         batadv_neigh_node_put(neigh_node);
398                         if (n_ifinfo)
399                                 batadv_neigh_ifinfo_put(n_ifinfo);
400                 }
401                 rcu_read_unlock();
402         }
403
404         if (batman_count == 0)
405                 seq_puts(seq, "No batman nodes in range ...\n");
406 }
407 #endif
408
409 /**
410  * batadv_v_orig_dump_subentry() - Dump an originator subentry into a message
411  * @msg: Netlink message to dump into
412  * @portid: Port making netlink request
413  * @seq: Sequence number of netlink message
414  * @bat_priv: The bat priv with all the soft interface information
415  * @if_outgoing: Limit dump to entries with this outgoing interface
416  * @orig_node: Originator to dump
417  * @neigh_node: Single hops neighbour
418  * @best: Is the best originator
419  *
420  * Return: Error code, or 0 on success
421  */
422 static int
423 batadv_v_orig_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
424                             struct batadv_priv *bat_priv,
425                             struct batadv_hard_iface *if_outgoing,
426                             struct batadv_orig_node *orig_node,
427                             struct batadv_neigh_node *neigh_node,
428                             bool best)
429 {
430         struct batadv_neigh_ifinfo *n_ifinfo;
431         unsigned int last_seen_msecs;
432         u32 throughput;
433         void *hdr;
434
435         n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
436         if (!n_ifinfo)
437                 return 0;
438
439         throughput = n_ifinfo->bat_v.throughput * 100;
440
441         batadv_neigh_ifinfo_put(n_ifinfo);
442
443         last_seen_msecs = jiffies_to_msecs(jiffies - orig_node->last_seen);
444
445         if (if_outgoing != BATADV_IF_DEFAULT &&
446             if_outgoing != neigh_node->if_incoming)
447                 return 0;
448
449         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
450                           BATADV_CMD_GET_ORIGINATORS);
451         if (!hdr)
452                 return -ENOBUFS;
453
454         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN, orig_node->orig) ||
455             nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
456                     neigh_node->addr) ||
457             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
458                         neigh_node->if_incoming->net_dev->ifindex) ||
459             nla_put_u32(msg, BATADV_ATTR_THROUGHPUT, throughput) ||
460             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
461                         last_seen_msecs))
462                 goto nla_put_failure;
463
464         if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
465                 goto nla_put_failure;
466
467         genlmsg_end(msg, hdr);
468         return 0;
469
470  nla_put_failure:
471         genlmsg_cancel(msg, hdr);
472         return -EMSGSIZE;
473 }
474
475 /**
476  * batadv_v_orig_dump_entry() - Dump an originator entry into a message
477  * @msg: Netlink message to dump into
478  * @portid: Port making netlink request
479  * @seq: Sequence number of netlink message
480  * @bat_priv: The bat priv with all the soft interface information
481  * @if_outgoing: Limit dump to entries with this outgoing interface
482  * @orig_node: Originator to dump
483  * @sub_s: Number of sub entries to skip
484  *
485  * This function assumes the caller holds rcu_read_lock().
486  *
487  * Return: Error code, or 0 on success
488  */
489 static int
490 batadv_v_orig_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
491                          struct batadv_priv *bat_priv,
492                          struct batadv_hard_iface *if_outgoing,
493                          struct batadv_orig_node *orig_node, int *sub_s)
494 {
495         struct batadv_neigh_node *neigh_node_best;
496         struct batadv_neigh_node *neigh_node;
497         int sub = 0;
498         bool best;
499
500         neigh_node_best = batadv_orig_router_get(orig_node, if_outgoing);
501         if (!neigh_node_best)
502                 goto out;
503
504         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
505                 if (sub++ < *sub_s)
506                         continue;
507
508                 best = (neigh_node == neigh_node_best);
509
510                 if (batadv_v_orig_dump_subentry(msg, portid, seq, bat_priv,
511                                                 if_outgoing, orig_node,
512                                                 neigh_node, best)) {
513                         batadv_neigh_node_put(neigh_node_best);
514
515                         *sub_s = sub - 1;
516                         return -EMSGSIZE;
517                 }
518         }
519
520  out:
521         if (neigh_node_best)
522                 batadv_neigh_node_put(neigh_node_best);
523
524         *sub_s = 0;
525         return 0;
526 }
527
528 /**
529  * batadv_v_orig_dump_bucket() - Dump an originator bucket into a message
530  * @msg: Netlink message to dump into
531  * @portid: Port making netlink request
532  * @seq: Sequence number of netlink message
533  * @bat_priv: The bat priv with all the soft interface information
534  * @if_outgoing: Limit dump to entries with this outgoing interface
535  * @head: Bucket to be dumped
536  * @idx_s: Number of entries to be skipped
537  * @sub: Number of sub entries to be skipped
538  *
539  * Return: Error code, or 0 on success
540  */
541 static int
542 batadv_v_orig_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
543                           struct batadv_priv *bat_priv,
544                           struct batadv_hard_iface *if_outgoing,
545                           struct hlist_head *head, int *idx_s, int *sub)
546 {
547         struct batadv_orig_node *orig_node;
548         int idx = 0;
549
550         rcu_read_lock();
551         hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
552                 if (idx++ < *idx_s)
553                         continue;
554
555                 if (batadv_v_orig_dump_entry(msg, portid, seq, bat_priv,
556                                              if_outgoing, orig_node, sub)) {
557                         rcu_read_unlock();
558                         *idx_s = idx - 1;
559                         return -EMSGSIZE;
560                 }
561         }
562         rcu_read_unlock();
563
564         *idx_s = 0;
565         *sub = 0;
566         return 0;
567 }
568
569 /**
570  * batadv_v_orig_dump() - Dump the originators into a message
571  * @msg: Netlink message to dump into
572  * @cb: Control block containing additional options
573  * @bat_priv: The bat priv with all the soft interface information
574  * @if_outgoing: Limit dump to entries with this outgoing interface
575  */
576 static void
577 batadv_v_orig_dump(struct sk_buff *msg, struct netlink_callback *cb,
578                    struct batadv_priv *bat_priv,
579                    struct batadv_hard_iface *if_outgoing)
580 {
581         struct batadv_hashtable *hash = bat_priv->orig_hash;
582         struct hlist_head *head;
583         int bucket = cb->args[0];
584         int idx = cb->args[1];
585         int sub = cb->args[2];
586         int portid = NETLINK_CB(cb->skb).portid;
587
588         while (bucket < hash->size) {
589                 head = &hash->table[bucket];
590
591                 if (batadv_v_orig_dump_bucket(msg, portid,
592                                               cb->nlh->nlmsg_seq,
593                                               bat_priv, if_outgoing, head, &idx,
594                                               &sub))
595                         break;
596
597                 bucket++;
598         }
599
600         cb->args[0] = bucket;
601         cb->args[1] = idx;
602         cb->args[2] = sub;
603 }
604
605 static int batadv_v_neigh_cmp(struct batadv_neigh_node *neigh1,
606                               struct batadv_hard_iface *if_outgoing1,
607                               struct batadv_neigh_node *neigh2,
608                               struct batadv_hard_iface *if_outgoing2)
609 {
610         struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
611         int ret = 0;
612
613         ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
614         if (!ifinfo1)
615                 goto err_ifinfo1;
616
617         ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
618         if (!ifinfo2)
619                 goto err_ifinfo2;
620
621         ret = ifinfo1->bat_v.throughput - ifinfo2->bat_v.throughput;
622
623         batadv_neigh_ifinfo_put(ifinfo2);
624 err_ifinfo2:
625         batadv_neigh_ifinfo_put(ifinfo1);
626 err_ifinfo1:
627         return ret;
628 }
629
630 static bool batadv_v_neigh_is_sob(struct batadv_neigh_node *neigh1,
631                                   struct batadv_hard_iface *if_outgoing1,
632                                   struct batadv_neigh_node *neigh2,
633                                   struct batadv_hard_iface *if_outgoing2)
634 {
635         struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
636         u32 threshold;
637         bool ret = false;
638
639         ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
640         if (!ifinfo1)
641                 goto err_ifinfo1;
642
643         ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
644         if (!ifinfo2)
645                 goto err_ifinfo2;
646
647         threshold = ifinfo1->bat_v.throughput / 4;
648         threshold = ifinfo1->bat_v.throughput - threshold;
649
650         ret = ifinfo2->bat_v.throughput > threshold;
651
652         batadv_neigh_ifinfo_put(ifinfo2);
653 err_ifinfo2:
654         batadv_neigh_ifinfo_put(ifinfo1);
655 err_ifinfo1:
656         return ret;
657 }
658
659 /**
660  * batadv_v_init_sel_class() - initialize GW selection class
661  * @bat_priv: the bat priv with all the soft interface information
662  */
663 static void batadv_v_init_sel_class(struct batadv_priv *bat_priv)
664 {
665         /* set default throughput difference threshold to 5Mbps */
666         atomic_set(&bat_priv->gw.sel_class, 50);
667 }
668
669 static ssize_t batadv_v_store_sel_class(struct batadv_priv *bat_priv,
670                                         char *buff, size_t count)
671 {
672         u32 old_class, class;
673
674         if (!batadv_parse_throughput(bat_priv->soft_iface, buff,
675                                      "B.A.T.M.A.N. V GW selection class",
676                                      &class))
677                 return -EINVAL;
678
679         old_class = atomic_read(&bat_priv->gw.sel_class);
680         atomic_set(&bat_priv->gw.sel_class, class);
681
682         if (old_class != class)
683                 batadv_gw_reselect(bat_priv);
684
685         return count;
686 }
687
688 static ssize_t batadv_v_show_sel_class(struct batadv_priv *bat_priv, char *buff)
689 {
690         u32 class = atomic_read(&bat_priv->gw.sel_class);
691
692         return sprintf(buff, "%u.%u MBit\n", class / 10, class % 10);
693 }
694
695 /**
696  * batadv_v_gw_throughput_get() - retrieve the GW-bandwidth for a given GW
697  * @gw_node: the GW to retrieve the metric for
698  * @bw: the pointer where the metric will be stored. The metric is computed as
699  *  the minimum between the GW advertised throughput and the path throughput to
700  *  it in the mesh
701  *
702  * Return: 0 on success, -1 on failure
703  */
704 static int batadv_v_gw_throughput_get(struct batadv_gw_node *gw_node, u32 *bw)
705 {
706         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
707         struct batadv_orig_node *orig_node;
708         struct batadv_neigh_node *router;
709         int ret = -1;
710
711         orig_node = gw_node->orig_node;
712         router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
713         if (!router)
714                 goto out;
715
716         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
717         if (!router_ifinfo)
718                 goto out;
719
720         /* the GW metric is computed as the minimum between the path throughput
721          * to reach the GW itself and the advertised bandwidth.
722          * This gives us an approximation of the effective throughput that the
723          * client can expect via this particular GW node
724          */
725         *bw = router_ifinfo->bat_v.throughput;
726         *bw = min_t(u32, *bw, gw_node->bandwidth_down);
727
728         ret = 0;
729 out:
730         if (router)
731                 batadv_neigh_node_put(router);
732         if (router_ifinfo)
733                 batadv_neigh_ifinfo_put(router_ifinfo);
734
735         return ret;
736 }
737
738 /**
739  * batadv_v_gw_get_best_gw_node() - retrieve the best GW node
740  * @bat_priv: the bat priv with all the soft interface information
741  *
742  * Return: the GW node having the best GW-metric, NULL if no GW is known
743  */
744 static struct batadv_gw_node *
745 batadv_v_gw_get_best_gw_node(struct batadv_priv *bat_priv)
746 {
747         struct batadv_gw_node *gw_node, *curr_gw = NULL;
748         u32 max_bw = 0, bw;
749
750         rcu_read_lock();
751         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
752                 if (!kref_get_unless_zero(&gw_node->refcount))
753                         continue;
754
755                 if (batadv_v_gw_throughput_get(gw_node, &bw) < 0)
756                         goto next;
757
758                 if (curr_gw && bw <= max_bw)
759                         goto next;
760
761                 if (curr_gw)
762                         batadv_gw_node_put(curr_gw);
763
764                 curr_gw = gw_node;
765                 kref_get(&curr_gw->refcount);
766                 max_bw = bw;
767
768 next:
769                 batadv_gw_node_put(gw_node);
770         }
771         rcu_read_unlock();
772
773         return curr_gw;
774 }
775
776 /**
777  * batadv_v_gw_is_eligible() - check if a originator would be selected as GW
778  * @bat_priv: the bat priv with all the soft interface information
779  * @curr_gw_orig: originator representing the currently selected GW
780  * @orig_node: the originator representing the new candidate
781  *
782  * Return: true if orig_node can be selected as current GW, false otherwise
783  */
784 static bool batadv_v_gw_is_eligible(struct batadv_priv *bat_priv,
785                                     struct batadv_orig_node *curr_gw_orig,
786                                     struct batadv_orig_node *orig_node)
787 {
788         struct batadv_gw_node *curr_gw, *orig_gw = NULL;
789         u32 gw_throughput, orig_throughput, threshold;
790         bool ret = false;
791
792         threshold = atomic_read(&bat_priv->gw.sel_class);
793
794         curr_gw = batadv_gw_node_get(bat_priv, curr_gw_orig);
795         if (!curr_gw) {
796                 ret = true;
797                 goto out;
798         }
799
800         if (batadv_v_gw_throughput_get(curr_gw, &gw_throughput) < 0) {
801                 ret = true;
802                 goto out;
803         }
804
805         orig_gw = batadv_gw_node_get(bat_priv, orig_node);
806         if (!orig_gw)
807                 goto out;
808
809         if (batadv_v_gw_throughput_get(orig_gw, &orig_throughput) < 0)
810                 goto out;
811
812         if (orig_throughput < gw_throughput)
813                 goto out;
814
815         if ((orig_throughput - gw_throughput) < threshold)
816                 goto out;
817
818         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
819                    "Restarting gateway selection: better gateway found (throughput curr: %u, throughput new: %u)\n",
820                    gw_throughput, orig_throughput);
821
822         ret = true;
823 out:
824         if (curr_gw)
825                 batadv_gw_node_put(curr_gw);
826         if (orig_gw)
827                 batadv_gw_node_put(orig_gw);
828
829         return ret;
830 }
831
832 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
833 /* fails if orig_node has no router */
834 static int batadv_v_gw_write_buffer_text(struct batadv_priv *bat_priv,
835                                          struct seq_file *seq,
836                                          const struct batadv_gw_node *gw_node)
837 {
838         struct batadv_gw_node *curr_gw;
839         struct batadv_neigh_node *router;
840         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
841         int ret = -1;
842
843         router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
844         if (!router)
845                 goto out;
846
847         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
848         if (!router_ifinfo)
849                 goto out;
850
851         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
852
853         seq_printf(seq, "%s %pM (%9u.%1u) %pM [%10s]: %u.%u/%u.%u MBit\n",
854                    (curr_gw == gw_node ? "=>" : "  "),
855                    gw_node->orig_node->orig,
856                    router_ifinfo->bat_v.throughput / 10,
857                    router_ifinfo->bat_v.throughput % 10, router->addr,
858                    router->if_incoming->net_dev->name,
859                    gw_node->bandwidth_down / 10,
860                    gw_node->bandwidth_down % 10,
861                    gw_node->bandwidth_up / 10,
862                    gw_node->bandwidth_up % 10);
863         ret = seq_has_overflowed(seq) ? -1 : 0;
864
865         if (curr_gw)
866                 batadv_gw_node_put(curr_gw);
867 out:
868         if (router_ifinfo)
869                 batadv_neigh_ifinfo_put(router_ifinfo);
870         if (router)
871                 batadv_neigh_node_put(router);
872         return ret;
873 }
874
875 /**
876  * batadv_v_gw_print() - print the gateway list
877  * @bat_priv: the bat priv with all the soft interface information
878  * @seq: gateway table seq_file struct
879  */
880 static void batadv_v_gw_print(struct batadv_priv *bat_priv,
881                               struct seq_file *seq)
882 {
883         struct batadv_gw_node *gw_node;
884         int gw_count = 0;
885
886         seq_puts(seq,
887                  "      Gateway        ( throughput)           Nexthop [outgoingIF]: advertised uplink bandwidth\n");
888
889         rcu_read_lock();
890         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
891                 /* fails if orig_node has no router */
892                 if (batadv_v_gw_write_buffer_text(bat_priv, seq, gw_node) < 0)
893                         continue;
894
895                 gw_count++;
896         }
897         rcu_read_unlock();
898
899         if (gw_count == 0)
900                 seq_puts(seq, "No gateways in range ...\n");
901 }
902 #endif
903
904 /**
905  * batadv_v_gw_dump_entry() - Dump a gateway into a message
906  * @msg: Netlink message to dump into
907  * @portid: Port making netlink request
908  * @cb: Control block containing additional options
909  * @bat_priv: The bat priv with all the soft interface information
910  * @gw_node: Gateway to be dumped
911  *
912  * Return: Error code, or 0 on success
913  */
914 static int batadv_v_gw_dump_entry(struct sk_buff *msg, u32 portid,
915                                   struct netlink_callback *cb,
916                                   struct batadv_priv *bat_priv,
917                                   struct batadv_gw_node *gw_node)
918 {
919         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
920         struct batadv_neigh_node *router;
921         struct batadv_gw_node *curr_gw = NULL;
922         int ret = 0;
923         void *hdr;
924
925         router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
926         if (!router)
927                 goto out;
928
929         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
930         if (!router_ifinfo)
931                 goto out;
932
933         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
934
935         hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
936                           &batadv_netlink_family, NLM_F_MULTI,
937                           BATADV_CMD_GET_GATEWAYS);
938         if (!hdr) {
939                 ret = -ENOBUFS;
940                 goto out;
941         }
942
943         genl_dump_check_consistent(cb, hdr);
944
945         ret = -EMSGSIZE;
946
947         if (curr_gw == gw_node) {
948                 if (nla_put_flag(msg, BATADV_ATTR_FLAG_BEST)) {
949                         genlmsg_cancel(msg, hdr);
950                         goto out;
951                 }
952         }
953
954         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
955                     gw_node->orig_node->orig)) {
956                 genlmsg_cancel(msg, hdr);
957                 goto out;
958         }
959
960         if (nla_put_u32(msg, BATADV_ATTR_THROUGHPUT,
961                         router_ifinfo->bat_v.throughput)) {
962                 genlmsg_cancel(msg, hdr);
963                 goto out;
964         }
965
966         if (nla_put(msg, BATADV_ATTR_ROUTER, ETH_ALEN, router->addr)) {
967                 genlmsg_cancel(msg, hdr);
968                 goto out;
969         }
970
971         if (nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
972                            router->if_incoming->net_dev->name)) {
973                 genlmsg_cancel(msg, hdr);
974                 goto out;
975         }
976
977         if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_DOWN,
978                         gw_node->bandwidth_down)) {
979                 genlmsg_cancel(msg, hdr);
980                 goto out;
981         }
982
983         if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_UP, gw_node->bandwidth_up)) {
984                 genlmsg_cancel(msg, hdr);
985                 goto out;
986         }
987
988         genlmsg_end(msg, hdr);
989         ret = 0;
990
991 out:
992         if (curr_gw)
993                 batadv_gw_node_put(curr_gw);
994         if (router_ifinfo)
995                 batadv_neigh_ifinfo_put(router_ifinfo);
996         if (router)
997                 batadv_neigh_node_put(router);
998         return ret;
999 }
1000
1001 /**
1002  * batadv_v_gw_dump() - Dump gateways into a message
1003  * @msg: Netlink message to dump into
1004  * @cb: Control block containing additional options
1005  * @bat_priv: The bat priv with all the soft interface information
1006  */
1007 static void batadv_v_gw_dump(struct sk_buff *msg, struct netlink_callback *cb,
1008                              struct batadv_priv *bat_priv)
1009 {
1010         int portid = NETLINK_CB(cb->skb).portid;
1011         struct batadv_gw_node *gw_node;
1012         int idx_skip = cb->args[0];
1013         int idx = 0;
1014
1015         spin_lock_bh(&bat_priv->gw.list_lock);
1016         cb->seq = bat_priv->gw.generation << 1 | 1;
1017
1018         hlist_for_each_entry(gw_node, &bat_priv->gw.gateway_list, list) {
1019                 if (idx++ < idx_skip)
1020                         continue;
1021
1022                 if (batadv_v_gw_dump_entry(msg, portid, cb, bat_priv,
1023                                            gw_node)) {
1024                         idx_skip = idx - 1;
1025                         goto unlock;
1026                 }
1027         }
1028
1029         idx_skip = idx;
1030 unlock:
1031         spin_unlock_bh(&bat_priv->gw.list_lock);
1032
1033         cb->args[0] = idx_skip;
1034 }
1035
1036 static struct batadv_algo_ops batadv_batman_v __read_mostly = {
1037         .name = "BATMAN_V",
1038         .iface = {
1039                 .activate = batadv_v_iface_activate,
1040                 .enable = batadv_v_iface_enable,
1041                 .disable = batadv_v_iface_disable,
1042                 .update_mac = batadv_v_iface_update_mac,
1043                 .primary_set = batadv_v_primary_iface_set,
1044         },
1045         .neigh = {
1046                 .hardif_init = batadv_v_hardif_neigh_init,
1047                 .cmp = batadv_v_neigh_cmp,
1048                 .is_similar_or_better = batadv_v_neigh_is_sob,
1049 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1050                 .print = batadv_v_neigh_print,
1051 #endif
1052                 .dump = batadv_v_neigh_dump,
1053         },
1054         .orig = {
1055 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1056                 .print = batadv_v_orig_print,
1057 #endif
1058                 .dump = batadv_v_orig_dump,
1059         },
1060         .gw = {
1061                 .init_sel_class = batadv_v_init_sel_class,
1062                 .store_sel_class = batadv_v_store_sel_class,
1063                 .show_sel_class = batadv_v_show_sel_class,
1064                 .get_best_gw_node = batadv_v_gw_get_best_gw_node,
1065                 .is_eligible = batadv_v_gw_is_eligible,
1066 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1067                 .print = batadv_v_gw_print,
1068 #endif
1069                 .dump = batadv_v_gw_dump,
1070         },
1071 };
1072
1073 /**
1074  * batadv_v_hardif_init() - initialize the algorithm specific fields in the
1075  *  hard-interface object
1076  * @hard_iface: the hard-interface to initialize
1077  */
1078 void batadv_v_hardif_init(struct batadv_hard_iface *hard_iface)
1079 {
1080         /* enable link throughput auto-detection by setting the throughput
1081          * override to zero
1082          */
1083         atomic_set(&hard_iface->bat_v.throughput_override, 0);
1084         atomic_set(&hard_iface->bat_v.elp_interval, 500);
1085
1086         hard_iface->bat_v.aggr_len = 0;
1087         skb_queue_head_init(&hard_iface->bat_v.aggr_list);
1088         INIT_DELAYED_WORK(&hard_iface->bat_v.aggr_wq,
1089                           batadv_v_ogm_aggr_work);
1090 }
1091
1092 /**
1093  * batadv_v_mesh_init() - initialize the B.A.T.M.A.N. V private resources for a
1094  *  mesh
1095  * @bat_priv: the object representing the mesh interface to initialise
1096  *
1097  * Return: 0 on success or a negative error code otherwise
1098  */
1099 int batadv_v_mesh_init(struct batadv_priv *bat_priv)
1100 {
1101         int ret = 0;
1102
1103         ret = batadv_v_ogm_init(bat_priv);
1104         if (ret < 0)
1105                 return ret;
1106
1107         return 0;
1108 }
1109
1110 /**
1111  * batadv_v_mesh_free() - free the B.A.T.M.A.N. V private resources for a mesh
1112  * @bat_priv: the object representing the mesh interface to free
1113  */
1114 void batadv_v_mesh_free(struct batadv_priv *bat_priv)
1115 {
1116         batadv_v_ogm_free(bat_priv);
1117 }
1118
1119 /**
1120  * batadv_v_init() - B.A.T.M.A.N. V initialization function
1121  *
1122  * Description: Takes care of initializing all the subcomponents.
1123  * It is invoked upon module load only.
1124  *
1125  * Return: 0 on success or a negative error code otherwise
1126  */
1127 int __init batadv_v_init(void)
1128 {
1129         int ret;
1130
1131         /* B.A.T.M.A.N. V echo location protocol packet  */
1132         ret = batadv_recv_handler_register(BATADV_ELP,
1133                                            batadv_v_elp_packet_recv);
1134         if (ret < 0)
1135                 return ret;
1136
1137         ret = batadv_recv_handler_register(BATADV_OGM2,
1138                                            batadv_v_ogm_packet_recv);
1139         if (ret < 0)
1140                 goto elp_unregister;
1141
1142         ret = batadv_algo_register(&batadv_batman_v);
1143         if (ret < 0)
1144                 goto ogm_unregister;
1145
1146         return ret;
1147
1148 ogm_unregister:
1149         batadv_recv_handler_unregister(BATADV_OGM2);
1150
1151 elp_unregister:
1152         batadv_recv_handler_unregister(BATADV_ELP);
1153
1154         return ret;
1155 }