Merge tag 'drm-next-2021-05-10' of git://anongit.freedesktop.org/drm/drm
[linux-2.6-microblaze.git] / net / batman-adv / bat_v.c
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 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/kref.h>
17 #include <linux/list.h>
18 #include <linux/minmax.h>
19 #include <linux/netdevice.h>
20 #include <linux/netlink.h>
21 #include <linux/rculist.h>
22 #include <linux/rcupdate.h>
23 #include <linux/skbuff.h>
24 #include <linux/spinlock.h>
25 #include <linux/stddef.h>
26 #include <linux/types.h>
27 #include <linux/workqueue.h>
28 #include <net/genetlink.h>
29 #include <net/netlink.h>
30 #include <uapi/linux/batadv_packet.h>
31 #include <uapi/linux/batman_adv.h>
32
33 #include "bat_algo.h"
34 #include "bat_v_elp.h"
35 #include "bat_v_ogm.h"
36 #include "gateway_client.h"
37 #include "gateway_common.h"
38 #include "hard-interface.h"
39 #include "hash.h"
40 #include "log.h"
41 #include "netlink.h"
42 #include "originator.h"
43
44 static void batadv_v_iface_activate(struct batadv_hard_iface *hard_iface)
45 {
46         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
47         struct batadv_hard_iface *primary_if;
48
49         primary_if = batadv_primary_if_get_selected(bat_priv);
50
51         if (primary_if) {
52                 batadv_v_elp_iface_activate(primary_if, hard_iface);
53                 batadv_hardif_put(primary_if);
54         }
55
56         /* B.A.T.M.A.N. V does not use any queuing mechanism, therefore it can
57          * set the interface as ACTIVE right away, without any risk of race
58          * condition
59          */
60         if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
61                 hard_iface->if_status = BATADV_IF_ACTIVE;
62 }
63
64 static int batadv_v_iface_enable(struct batadv_hard_iface *hard_iface)
65 {
66         int ret;
67
68         ret = batadv_v_elp_iface_enable(hard_iface);
69         if (ret < 0)
70                 return ret;
71
72         ret = batadv_v_ogm_iface_enable(hard_iface);
73         if (ret < 0)
74                 batadv_v_elp_iface_disable(hard_iface);
75
76         return ret;
77 }
78
79 static void batadv_v_iface_disable(struct batadv_hard_iface *hard_iface)
80 {
81         batadv_v_ogm_iface_disable(hard_iface);
82         batadv_v_elp_iface_disable(hard_iface);
83 }
84
85 static void batadv_v_primary_iface_set(struct batadv_hard_iface *hard_iface)
86 {
87         batadv_v_elp_primary_iface_set(hard_iface);
88         batadv_v_ogm_primary_iface_set(hard_iface);
89 }
90
91 /**
92  * batadv_v_iface_update_mac() - react to hard-interface MAC address change
93  * @hard_iface: the modified interface
94  *
95  * If the modified interface is the primary one, update the originator
96  * address in the ELP and OGM messages to reflect the new MAC address.
97  */
98 static void batadv_v_iface_update_mac(struct batadv_hard_iface *hard_iface)
99 {
100         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
101         struct batadv_hard_iface *primary_if;
102
103         primary_if = batadv_primary_if_get_selected(bat_priv);
104         if (primary_if != hard_iface)
105                 goto out;
106
107         batadv_v_primary_iface_set(hard_iface);
108 out:
109         if (primary_if)
110                 batadv_hardif_put(primary_if);
111 }
112
113 static void
114 batadv_v_hardif_neigh_init(struct batadv_hardif_neigh_node *hardif_neigh)
115 {
116         ewma_throughput_init(&hardif_neigh->bat_v.throughput);
117         INIT_WORK(&hardif_neigh->bat_v.metric_work,
118                   batadv_v_elp_throughput_metric_update);
119 }
120
121 /**
122  * batadv_v_neigh_dump_neigh() - Dump a neighbour into a message
123  * @msg: Netlink message to dump into
124  * @portid: Port making netlink request
125  * @seq: Sequence number of netlink message
126  * @hardif_neigh: Neighbour to dump
127  *
128  * Return: Error code, or 0 on success
129  */
130 static int
131 batadv_v_neigh_dump_neigh(struct sk_buff *msg, u32 portid, u32 seq,
132                           struct batadv_hardif_neigh_node *hardif_neigh)
133 {
134         void *hdr;
135         unsigned int last_seen_msecs;
136         u32 throughput;
137
138         last_seen_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen);
139         throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput);
140         throughput = throughput * 100;
141
142         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
143                           BATADV_CMD_GET_NEIGHBORS);
144         if (!hdr)
145                 return -ENOBUFS;
146
147         if (nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
148                     hardif_neigh->addr) ||
149             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
150                         hardif_neigh->if_incoming->net_dev->ifindex) ||
151             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
152                         last_seen_msecs) ||
153             nla_put_u32(msg, BATADV_ATTR_THROUGHPUT, throughput))
154                 goto nla_put_failure;
155
156         genlmsg_end(msg, hdr);
157         return 0;
158
159  nla_put_failure:
160         genlmsg_cancel(msg, hdr);
161         return -EMSGSIZE;
162 }
163
164 /**
165  * batadv_v_neigh_dump_hardif() - Dump the  neighbours of a hard interface into
166  *  a message
167  * @msg: Netlink message to dump into
168  * @portid: Port making netlink request
169  * @seq: Sequence number of netlink message
170  * @bat_priv: The bat priv with all the soft interface information
171  * @hard_iface: The hard interface to be dumped
172  * @idx_s: Entries to be skipped
173  *
174  * This function assumes the caller holds rcu_read_lock().
175  *
176  * Return: Error code, or 0 on success
177  */
178 static int
179 batadv_v_neigh_dump_hardif(struct sk_buff *msg, u32 portid, u32 seq,
180                            struct batadv_priv *bat_priv,
181                            struct batadv_hard_iface *hard_iface,
182                            int *idx_s)
183 {
184         struct batadv_hardif_neigh_node *hardif_neigh;
185         int idx = 0;
186
187         hlist_for_each_entry_rcu(hardif_neigh,
188                                  &hard_iface->neigh_list, list) {
189                 if (idx++ < *idx_s)
190                         continue;
191
192                 if (batadv_v_neigh_dump_neigh(msg, portid, seq, hardif_neigh)) {
193                         *idx_s = idx - 1;
194                         return -EMSGSIZE;
195                 }
196         }
197
198         *idx_s = 0;
199         return 0;
200 }
201
202 /**
203  * batadv_v_neigh_dump() - Dump the neighbours of a hard interface  into a
204  *  message
205  * @msg: Netlink message to dump into
206  * @cb: Control block containing additional options
207  * @bat_priv: The bat priv with all the soft interface information
208  * @single_hardif: Limit dumping to this hard interface
209  */
210 static void
211 batadv_v_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb,
212                     struct batadv_priv *bat_priv,
213                     struct batadv_hard_iface *single_hardif)
214 {
215         struct batadv_hard_iface *hard_iface;
216         int i_hardif = 0;
217         int i_hardif_s = cb->args[0];
218         int idx = cb->args[1];
219         int portid = NETLINK_CB(cb->skb).portid;
220
221         rcu_read_lock();
222         if (single_hardif) {
223                 if (i_hardif_s == 0) {
224                         if (batadv_v_neigh_dump_hardif(msg, portid,
225                                                        cb->nlh->nlmsg_seq,
226                                                        bat_priv, single_hardif,
227                                                        &idx) == 0)
228                                 i_hardif++;
229                 }
230         } else {
231                 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
232                         if (hard_iface->soft_iface != bat_priv->soft_iface)
233                                 continue;
234
235                         if (i_hardif++ < i_hardif_s)
236                                 continue;
237
238                         if (batadv_v_neigh_dump_hardif(msg, portid,
239                                                        cb->nlh->nlmsg_seq,
240                                                        bat_priv, hard_iface,
241                                                        &idx)) {
242                                 i_hardif--;
243                                 break;
244                         }
245                 }
246         }
247         rcu_read_unlock();
248
249         cb->args[0] = i_hardif;
250         cb->args[1] = idx;
251 }
252
253 /**
254  * batadv_v_orig_dump_subentry() - Dump an originator subentry into a message
255  * @msg: Netlink message to dump into
256  * @portid: Port making netlink request
257  * @seq: Sequence number of netlink message
258  * @bat_priv: The bat priv with all the soft interface information
259  * @if_outgoing: Limit dump to entries with this outgoing interface
260  * @orig_node: Originator to dump
261  * @neigh_node: Single hops neighbour
262  * @best: Is the best originator
263  *
264  * Return: Error code, or 0 on success
265  */
266 static int
267 batadv_v_orig_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
268                             struct batadv_priv *bat_priv,
269                             struct batadv_hard_iface *if_outgoing,
270                             struct batadv_orig_node *orig_node,
271                             struct batadv_neigh_node *neigh_node,
272                             bool best)
273 {
274         struct batadv_neigh_ifinfo *n_ifinfo;
275         unsigned int last_seen_msecs;
276         u32 throughput;
277         void *hdr;
278
279         n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
280         if (!n_ifinfo)
281                 return 0;
282
283         throughput = n_ifinfo->bat_v.throughput * 100;
284
285         batadv_neigh_ifinfo_put(n_ifinfo);
286
287         last_seen_msecs = jiffies_to_msecs(jiffies - orig_node->last_seen);
288
289         if (if_outgoing != BATADV_IF_DEFAULT &&
290             if_outgoing != neigh_node->if_incoming)
291                 return 0;
292
293         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
294                           BATADV_CMD_GET_ORIGINATORS);
295         if (!hdr)
296                 return -ENOBUFS;
297
298         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN, orig_node->orig) ||
299             nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
300                     neigh_node->addr) ||
301             nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
302                         neigh_node->if_incoming->net_dev->ifindex) ||
303             nla_put_u32(msg, BATADV_ATTR_THROUGHPUT, throughput) ||
304             nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
305                         last_seen_msecs))
306                 goto nla_put_failure;
307
308         if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
309                 goto nla_put_failure;
310
311         genlmsg_end(msg, hdr);
312         return 0;
313
314  nla_put_failure:
315         genlmsg_cancel(msg, hdr);
316         return -EMSGSIZE;
317 }
318
319 /**
320  * batadv_v_orig_dump_entry() - Dump an originator entry into a message
321  * @msg: Netlink message to dump into
322  * @portid: Port making netlink request
323  * @seq: Sequence number of netlink message
324  * @bat_priv: The bat priv with all the soft interface information
325  * @if_outgoing: Limit dump to entries with this outgoing interface
326  * @orig_node: Originator to dump
327  * @sub_s: Number of sub entries to skip
328  *
329  * This function assumes the caller holds rcu_read_lock().
330  *
331  * Return: Error code, or 0 on success
332  */
333 static int
334 batadv_v_orig_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
335                          struct batadv_priv *bat_priv,
336                          struct batadv_hard_iface *if_outgoing,
337                          struct batadv_orig_node *orig_node, int *sub_s)
338 {
339         struct batadv_neigh_node *neigh_node_best;
340         struct batadv_neigh_node *neigh_node;
341         int sub = 0;
342         bool best;
343
344         neigh_node_best = batadv_orig_router_get(orig_node, if_outgoing);
345         if (!neigh_node_best)
346                 goto out;
347
348         hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
349                 if (sub++ < *sub_s)
350                         continue;
351
352                 best = (neigh_node == neigh_node_best);
353
354                 if (batadv_v_orig_dump_subentry(msg, portid, seq, bat_priv,
355                                                 if_outgoing, orig_node,
356                                                 neigh_node, best)) {
357                         batadv_neigh_node_put(neigh_node_best);
358
359                         *sub_s = sub - 1;
360                         return -EMSGSIZE;
361                 }
362         }
363
364  out:
365         if (neigh_node_best)
366                 batadv_neigh_node_put(neigh_node_best);
367
368         *sub_s = 0;
369         return 0;
370 }
371
372 /**
373  * batadv_v_orig_dump_bucket() - Dump an originator bucket into a message
374  * @msg: Netlink message to dump into
375  * @portid: Port making netlink request
376  * @seq: Sequence number of netlink message
377  * @bat_priv: The bat priv with all the soft interface information
378  * @if_outgoing: Limit dump to entries with this outgoing interface
379  * @head: Bucket to be dumped
380  * @idx_s: Number of entries to be skipped
381  * @sub: Number of sub entries to be skipped
382  *
383  * Return: Error code, or 0 on success
384  */
385 static int
386 batadv_v_orig_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
387                           struct batadv_priv *bat_priv,
388                           struct batadv_hard_iface *if_outgoing,
389                           struct hlist_head *head, int *idx_s, int *sub)
390 {
391         struct batadv_orig_node *orig_node;
392         int idx = 0;
393
394         rcu_read_lock();
395         hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
396                 if (idx++ < *idx_s)
397                         continue;
398
399                 if (batadv_v_orig_dump_entry(msg, portid, seq, bat_priv,
400                                              if_outgoing, orig_node, sub)) {
401                         rcu_read_unlock();
402                         *idx_s = idx - 1;
403                         return -EMSGSIZE;
404                 }
405         }
406         rcu_read_unlock();
407
408         *idx_s = 0;
409         *sub = 0;
410         return 0;
411 }
412
413 /**
414  * batadv_v_orig_dump() - Dump the originators into a message
415  * @msg: Netlink message to dump into
416  * @cb: Control block containing additional options
417  * @bat_priv: The bat priv with all the soft interface information
418  * @if_outgoing: Limit dump to entries with this outgoing interface
419  */
420 static void
421 batadv_v_orig_dump(struct sk_buff *msg, struct netlink_callback *cb,
422                    struct batadv_priv *bat_priv,
423                    struct batadv_hard_iface *if_outgoing)
424 {
425         struct batadv_hashtable *hash = bat_priv->orig_hash;
426         struct hlist_head *head;
427         int bucket = cb->args[0];
428         int idx = cb->args[1];
429         int sub = cb->args[2];
430         int portid = NETLINK_CB(cb->skb).portid;
431
432         while (bucket < hash->size) {
433                 head = &hash->table[bucket];
434
435                 if (batadv_v_orig_dump_bucket(msg, portid,
436                                               cb->nlh->nlmsg_seq,
437                                               bat_priv, if_outgoing, head, &idx,
438                                               &sub))
439                         break;
440
441                 bucket++;
442         }
443
444         cb->args[0] = bucket;
445         cb->args[1] = idx;
446         cb->args[2] = sub;
447 }
448
449 static int batadv_v_neigh_cmp(struct batadv_neigh_node *neigh1,
450                               struct batadv_hard_iface *if_outgoing1,
451                               struct batadv_neigh_node *neigh2,
452                               struct batadv_hard_iface *if_outgoing2)
453 {
454         struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
455         int ret = 0;
456
457         ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
458         if (!ifinfo1)
459                 goto err_ifinfo1;
460
461         ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
462         if (!ifinfo2)
463                 goto err_ifinfo2;
464
465         ret = ifinfo1->bat_v.throughput - ifinfo2->bat_v.throughput;
466
467         batadv_neigh_ifinfo_put(ifinfo2);
468 err_ifinfo2:
469         batadv_neigh_ifinfo_put(ifinfo1);
470 err_ifinfo1:
471         return ret;
472 }
473
474 static bool batadv_v_neigh_is_sob(struct batadv_neigh_node *neigh1,
475                                   struct batadv_hard_iface *if_outgoing1,
476                                   struct batadv_neigh_node *neigh2,
477                                   struct batadv_hard_iface *if_outgoing2)
478 {
479         struct batadv_neigh_ifinfo *ifinfo1, *ifinfo2;
480         u32 threshold;
481         bool ret = false;
482
483         ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
484         if (!ifinfo1)
485                 goto err_ifinfo1;
486
487         ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
488         if (!ifinfo2)
489                 goto err_ifinfo2;
490
491         threshold = ifinfo1->bat_v.throughput / 4;
492         threshold = ifinfo1->bat_v.throughput - threshold;
493
494         ret = ifinfo2->bat_v.throughput > threshold;
495
496         batadv_neigh_ifinfo_put(ifinfo2);
497 err_ifinfo2:
498         batadv_neigh_ifinfo_put(ifinfo1);
499 err_ifinfo1:
500         return ret;
501 }
502
503 /**
504  * batadv_v_init_sel_class() - initialize GW selection class
505  * @bat_priv: the bat priv with all the soft interface information
506  */
507 static void batadv_v_init_sel_class(struct batadv_priv *bat_priv)
508 {
509         /* set default throughput difference threshold to 5Mbps */
510         atomic_set(&bat_priv->gw.sel_class, 50);
511 }
512
513 static ssize_t batadv_v_store_sel_class(struct batadv_priv *bat_priv,
514                                         char *buff, size_t count)
515 {
516         u32 old_class, class;
517
518         if (!batadv_parse_throughput(bat_priv->soft_iface, buff,
519                                      "B.A.T.M.A.N. V GW selection class",
520                                      &class))
521                 return -EINVAL;
522
523         old_class = atomic_read(&bat_priv->gw.sel_class);
524         atomic_set(&bat_priv->gw.sel_class, class);
525
526         if (old_class != class)
527                 batadv_gw_reselect(bat_priv);
528
529         return count;
530 }
531
532 /**
533  * batadv_v_gw_throughput_get() - retrieve the GW-bandwidth for a given GW
534  * @gw_node: the GW to retrieve the metric for
535  * @bw: the pointer where the metric will be stored. The metric is computed as
536  *  the minimum between the GW advertised throughput and the path throughput to
537  *  it in the mesh
538  *
539  * Return: 0 on success, -1 on failure
540  */
541 static int batadv_v_gw_throughput_get(struct batadv_gw_node *gw_node, u32 *bw)
542 {
543         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
544         struct batadv_orig_node *orig_node;
545         struct batadv_neigh_node *router;
546         int ret = -1;
547
548         orig_node = gw_node->orig_node;
549         router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
550         if (!router)
551                 goto out;
552
553         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
554         if (!router_ifinfo)
555                 goto out;
556
557         /* the GW metric is computed as the minimum between the path throughput
558          * to reach the GW itself and the advertised bandwidth.
559          * This gives us an approximation of the effective throughput that the
560          * client can expect via this particular GW node
561          */
562         *bw = router_ifinfo->bat_v.throughput;
563         *bw = min_t(u32, *bw, gw_node->bandwidth_down);
564
565         ret = 0;
566 out:
567         if (router)
568                 batadv_neigh_node_put(router);
569         if (router_ifinfo)
570                 batadv_neigh_ifinfo_put(router_ifinfo);
571
572         return ret;
573 }
574
575 /**
576  * batadv_v_gw_get_best_gw_node() - retrieve the best GW node
577  * @bat_priv: the bat priv with all the soft interface information
578  *
579  * Return: the GW node having the best GW-metric, NULL if no GW is known
580  */
581 static struct batadv_gw_node *
582 batadv_v_gw_get_best_gw_node(struct batadv_priv *bat_priv)
583 {
584         struct batadv_gw_node *gw_node, *curr_gw = NULL;
585         u32 max_bw = 0, bw;
586
587         rcu_read_lock();
588         hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
589                 if (!kref_get_unless_zero(&gw_node->refcount))
590                         continue;
591
592                 if (batadv_v_gw_throughput_get(gw_node, &bw) < 0)
593                         goto next;
594
595                 if (curr_gw && bw <= max_bw)
596                         goto next;
597
598                 if (curr_gw)
599                         batadv_gw_node_put(curr_gw);
600
601                 curr_gw = gw_node;
602                 kref_get(&curr_gw->refcount);
603                 max_bw = bw;
604
605 next:
606                 batadv_gw_node_put(gw_node);
607         }
608         rcu_read_unlock();
609
610         return curr_gw;
611 }
612
613 /**
614  * batadv_v_gw_is_eligible() - check if a originator would be selected as GW
615  * @bat_priv: the bat priv with all the soft interface information
616  * @curr_gw_orig: originator representing the currently selected GW
617  * @orig_node: the originator representing the new candidate
618  *
619  * Return: true if orig_node can be selected as current GW, false otherwise
620  */
621 static bool batadv_v_gw_is_eligible(struct batadv_priv *bat_priv,
622                                     struct batadv_orig_node *curr_gw_orig,
623                                     struct batadv_orig_node *orig_node)
624 {
625         struct batadv_gw_node *curr_gw, *orig_gw = NULL;
626         u32 gw_throughput, orig_throughput, threshold;
627         bool ret = false;
628
629         threshold = atomic_read(&bat_priv->gw.sel_class);
630
631         curr_gw = batadv_gw_node_get(bat_priv, curr_gw_orig);
632         if (!curr_gw) {
633                 ret = true;
634                 goto out;
635         }
636
637         if (batadv_v_gw_throughput_get(curr_gw, &gw_throughput) < 0) {
638                 ret = true;
639                 goto out;
640         }
641
642         orig_gw = batadv_gw_node_get(bat_priv, orig_node);
643         if (!orig_gw)
644                 goto out;
645
646         if (batadv_v_gw_throughput_get(orig_gw, &orig_throughput) < 0)
647                 goto out;
648
649         if (orig_throughput < gw_throughput)
650                 goto out;
651
652         if ((orig_throughput - gw_throughput) < threshold)
653                 goto out;
654
655         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
656                    "Restarting gateway selection: better gateway found (throughput curr: %u, throughput new: %u)\n",
657                    gw_throughput, orig_throughput);
658
659         ret = true;
660 out:
661         if (curr_gw)
662                 batadv_gw_node_put(curr_gw);
663         if (orig_gw)
664                 batadv_gw_node_put(orig_gw);
665
666         return ret;
667 }
668
669 /**
670  * batadv_v_gw_dump_entry() - Dump a gateway into a message
671  * @msg: Netlink message to dump into
672  * @portid: Port making netlink request
673  * @cb: Control block containing additional options
674  * @bat_priv: The bat priv with all the soft interface information
675  * @gw_node: Gateway to be dumped
676  *
677  * Return: Error code, or 0 on success
678  */
679 static int batadv_v_gw_dump_entry(struct sk_buff *msg, u32 portid,
680                                   struct netlink_callback *cb,
681                                   struct batadv_priv *bat_priv,
682                                   struct batadv_gw_node *gw_node)
683 {
684         struct batadv_neigh_ifinfo *router_ifinfo = NULL;
685         struct batadv_neigh_node *router;
686         struct batadv_gw_node *curr_gw = NULL;
687         int ret = 0;
688         void *hdr;
689
690         router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
691         if (!router)
692                 goto out;
693
694         router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
695         if (!router_ifinfo)
696                 goto out;
697
698         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
699
700         hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
701                           &batadv_netlink_family, NLM_F_MULTI,
702                           BATADV_CMD_GET_GATEWAYS);
703         if (!hdr) {
704                 ret = -ENOBUFS;
705                 goto out;
706         }
707
708         genl_dump_check_consistent(cb, hdr);
709
710         ret = -EMSGSIZE;
711
712         if (curr_gw == gw_node) {
713                 if (nla_put_flag(msg, BATADV_ATTR_FLAG_BEST)) {
714                         genlmsg_cancel(msg, hdr);
715                         goto out;
716                 }
717         }
718
719         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
720                     gw_node->orig_node->orig)) {
721                 genlmsg_cancel(msg, hdr);
722                 goto out;
723         }
724
725         if (nla_put_u32(msg, BATADV_ATTR_THROUGHPUT,
726                         router_ifinfo->bat_v.throughput)) {
727                 genlmsg_cancel(msg, hdr);
728                 goto out;
729         }
730
731         if (nla_put(msg, BATADV_ATTR_ROUTER, ETH_ALEN, router->addr)) {
732                 genlmsg_cancel(msg, hdr);
733                 goto out;
734         }
735
736         if (nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
737                            router->if_incoming->net_dev->name)) {
738                 genlmsg_cancel(msg, hdr);
739                 goto out;
740         }
741
742         if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_DOWN,
743                         gw_node->bandwidth_down)) {
744                 genlmsg_cancel(msg, hdr);
745                 goto out;
746         }
747
748         if (nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_UP, gw_node->bandwidth_up)) {
749                 genlmsg_cancel(msg, hdr);
750                 goto out;
751         }
752
753         genlmsg_end(msg, hdr);
754         ret = 0;
755
756 out:
757         if (curr_gw)
758                 batadv_gw_node_put(curr_gw);
759         if (router_ifinfo)
760                 batadv_neigh_ifinfo_put(router_ifinfo);
761         if (router)
762                 batadv_neigh_node_put(router);
763         return ret;
764 }
765
766 /**
767  * batadv_v_gw_dump() - Dump gateways into a message
768  * @msg: Netlink message to dump into
769  * @cb: Control block containing additional options
770  * @bat_priv: The bat priv with all the soft interface information
771  */
772 static void batadv_v_gw_dump(struct sk_buff *msg, struct netlink_callback *cb,
773                              struct batadv_priv *bat_priv)
774 {
775         int portid = NETLINK_CB(cb->skb).portid;
776         struct batadv_gw_node *gw_node;
777         int idx_skip = cb->args[0];
778         int idx = 0;
779
780         spin_lock_bh(&bat_priv->gw.list_lock);
781         cb->seq = bat_priv->gw.generation << 1 | 1;
782
783         hlist_for_each_entry(gw_node, &bat_priv->gw.gateway_list, list) {
784                 if (idx++ < idx_skip)
785                         continue;
786
787                 if (batadv_v_gw_dump_entry(msg, portid, cb, bat_priv,
788                                            gw_node)) {
789                         idx_skip = idx - 1;
790                         goto unlock;
791                 }
792         }
793
794         idx_skip = idx;
795 unlock:
796         spin_unlock_bh(&bat_priv->gw.list_lock);
797
798         cb->args[0] = idx_skip;
799 }
800
801 static struct batadv_algo_ops batadv_batman_v __read_mostly = {
802         .name = "BATMAN_V",
803         .iface = {
804                 .activate = batadv_v_iface_activate,
805                 .enable = batadv_v_iface_enable,
806                 .disable = batadv_v_iface_disable,
807                 .update_mac = batadv_v_iface_update_mac,
808                 .primary_set = batadv_v_primary_iface_set,
809         },
810         .neigh = {
811                 .hardif_init = batadv_v_hardif_neigh_init,
812                 .cmp = batadv_v_neigh_cmp,
813                 .is_similar_or_better = batadv_v_neigh_is_sob,
814                 .dump = batadv_v_neigh_dump,
815         },
816         .orig = {
817                 .dump = batadv_v_orig_dump,
818         },
819         .gw = {
820                 .init_sel_class = batadv_v_init_sel_class,
821                 .store_sel_class = batadv_v_store_sel_class,
822                 .get_best_gw_node = batadv_v_gw_get_best_gw_node,
823                 .is_eligible = batadv_v_gw_is_eligible,
824                 .dump = batadv_v_gw_dump,
825         },
826 };
827
828 /**
829  * batadv_v_hardif_init() - initialize the algorithm specific fields in the
830  *  hard-interface object
831  * @hard_iface: the hard-interface to initialize
832  */
833 void batadv_v_hardif_init(struct batadv_hard_iface *hard_iface)
834 {
835         /* enable link throughput auto-detection by setting the throughput
836          * override to zero
837          */
838         atomic_set(&hard_iface->bat_v.throughput_override, 0);
839         atomic_set(&hard_iface->bat_v.elp_interval, 500);
840
841         hard_iface->bat_v.aggr_len = 0;
842         skb_queue_head_init(&hard_iface->bat_v.aggr_list);
843         INIT_DELAYED_WORK(&hard_iface->bat_v.aggr_wq,
844                           batadv_v_ogm_aggr_work);
845 }
846
847 /**
848  * batadv_v_mesh_init() - initialize the B.A.T.M.A.N. V private resources for a
849  *  mesh
850  * @bat_priv: the object representing the mesh interface to initialise
851  *
852  * Return: 0 on success or a negative error code otherwise
853  */
854 int batadv_v_mesh_init(struct batadv_priv *bat_priv)
855 {
856         int ret = 0;
857
858         ret = batadv_v_ogm_init(bat_priv);
859         if (ret < 0)
860                 return ret;
861
862         return 0;
863 }
864
865 /**
866  * batadv_v_mesh_free() - free the B.A.T.M.A.N. V private resources for a mesh
867  * @bat_priv: the object representing the mesh interface to free
868  */
869 void batadv_v_mesh_free(struct batadv_priv *bat_priv)
870 {
871         batadv_v_ogm_free(bat_priv);
872 }
873
874 /**
875  * batadv_v_init() - B.A.T.M.A.N. V initialization function
876  *
877  * Description: Takes care of initializing all the subcomponents.
878  * It is invoked upon module load only.
879  *
880  * Return: 0 on success or a negative error code otherwise
881  */
882 int __init batadv_v_init(void)
883 {
884         int ret;
885
886         /* B.A.T.M.A.N. V echo location protocol packet  */
887         ret = batadv_recv_handler_register(BATADV_ELP,
888                                            batadv_v_elp_packet_recv);
889         if (ret < 0)
890                 return ret;
891
892         ret = batadv_recv_handler_register(BATADV_OGM2,
893                                            batadv_v_ogm_packet_recv);
894         if (ret < 0)
895                 goto elp_unregister;
896
897         ret = batadv_algo_register(&batadv_batman_v);
898         if (ret < 0)
899                 goto ogm_unregister;
900
901         return ret;
902
903 ogm_unregister:
904         batadv_recv_handler_unregister(BATADV_OGM2);
905
906 elp_unregister:
907         batadv_recv_handler_unregister(BATADV_ELP);
908
909         return ret;
910 }