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1/*
2 * net/tipc/monitor.c
3 *
4 * Copyright (c) 2016, Ericsson AB
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the names of the copyright holders nor the names of its
16 * contributors may be used to endorse or promote products derived from
17 * this software without specific prior written permission.
18 *
19 * Alternatively, this software may be distributed under the terms of the
20 * GNU General Public License ("GPL") version 2 as published by the Free
21 * Software Foundation.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
24 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
27 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33 * POSSIBILITY OF SUCH DAMAGE.
34 */
35
36#include <net/genetlink.h>
37#include "core.h"
38#include "addr.h"
39#include "monitor.h"
40#include "bearer.h"
41
42#define MAX_MON_DOMAIN 64
43#define MON_TIMEOUT 120000
44#define MAX_PEER_DOWN_EVENTS 4
45
46/* struct tipc_mon_domain: domain record to be transferred between peers
47 * @len: actual size of domain record
48 * @gen: current generation of sender's domain
49 * @ack_gen: most recent generation of self's domain acked by peer
50 * @member_cnt: number of domain member nodes described in this record
51 * @up_map: bit map indicating which of the members the sender considers up
52 * @members: identity of the domain members
53 */
54struct tipc_mon_domain {
55 u16 len;
56 u16 gen;
57 u16 ack_gen;
58 u16 member_cnt;
59 u64 up_map;
60 u32 members[MAX_MON_DOMAIN];
61};
62
63/* struct tipc_peer: state of a peer node and its domain
64 * @addr: tipc node identity of peer
65 * @head_map: shows which other nodes currently consider peer 'up'
66 * @domain: most recent domain record from peer
67 * @hash: position in hashed lookup list
68 * @list: position in linked list, in circular ascending order by 'addr'
69 * @applied: number of reported domain members applied on this monitor list
70 * @is_up: peer is up as seen from this node
71 * @is_head: peer is assigned domain head as seen from this node
72 * @is_local: peer is in local domain and should be continuously monitored
73 * @down_cnt: - numbers of other peers which have reported this on lost
74 */
75struct tipc_peer {
76 u32 addr;
77 struct tipc_mon_domain *domain;
78 struct hlist_node hash;
79 struct list_head list;
80 u8 applied;
81 u8 down_cnt;
82 bool is_up;
83 bool is_head;
84 bool is_local;
85};
86
87struct tipc_monitor {
88 struct hlist_head peers[NODE_HTABLE_SIZE];
89 int peer_cnt;
90 struct tipc_peer *self;
91 rwlock_t lock;
92 struct tipc_mon_domain cache;
93 u16 list_gen;
94 u16 dom_gen;
95 struct net *net;
96 struct timer_list timer;
97 unsigned long timer_intv;
98};
99
100static struct tipc_monitor *tipc_monitor(struct net *net, int bearer_id)
101{
102 return tipc_net(net)->monitors[bearer_id];
103}
104
105const int tipc_max_domain_size = sizeof(struct tipc_mon_domain);
106
107static inline u16 mon_cpu_to_le16(u16 val)
108{
109 return (__force __u16)htons(val);
110}
111
112static inline u32 mon_cpu_to_le32(u32 val)
113{
114 return (__force __u32)htonl(val);
115}
116
117static inline u64 mon_cpu_to_le64(u64 val)
118{
119 return (__force __u64)cpu_to_be64(val);
120}
121
122static inline u16 mon_le16_to_cpu(u16 val)
123{
124 return ntohs((__force __be16)val);
125}
126
127static inline u32 mon_le32_to_cpu(u32 val)
128{
129 return ntohl((__force __be32)val);
130}
131
132static inline u64 mon_le64_to_cpu(u64 val)
133{
134 return be64_to_cpu((__force __be64)val);
135}
136
137/* dom_rec_len(): actual length of domain record for transport
138 */
139static int dom_rec_len(struct tipc_mon_domain *dom, u16 mcnt)
140{
141 return (offsetof(struct tipc_mon_domain, members)) + (mcnt * sizeof(u32));
142}
143
144/* dom_size() : calculate size of own domain based on number of peers
145 */
146static int dom_size(int peers)
147{
148 int i = 0;
149
150 while ((i * i) < peers)
151 i++;
152 return i < MAX_MON_DOMAIN ? i : MAX_MON_DOMAIN;
153}
154
155static void map_set(u64 *up_map, int i, unsigned int v)
156{
157 *up_map &= ~(1ULL << i);
158 *up_map |= ((u64)v << i);
159}
160
161static int map_get(u64 up_map, int i)
162{
163 return (up_map & (1ULL << i)) >> i;
164}
165
166static struct tipc_peer *peer_prev(struct tipc_peer *peer)
167{
168 return list_last_entry(&peer->list, struct tipc_peer, list);
169}
170
171static struct tipc_peer *peer_nxt(struct tipc_peer *peer)
172{
173 return list_first_entry(&peer->list, struct tipc_peer, list);
174}
175
176static struct tipc_peer *peer_head(struct tipc_peer *peer)
177{
178 while (!peer->is_head)
179 peer = peer_prev(peer);
180 return peer;
181}
182
183static struct tipc_peer *get_peer(struct tipc_monitor *mon, u32 addr)
184{
185 struct tipc_peer *peer;
186 unsigned int thash = tipc_hashfn(addr);
187
188 hlist_for_each_entry(peer, &mon->peers[thash], hash) {
189 if (peer->addr == addr)
190 return peer;
191 }
192 return NULL;
193}
194
195static struct tipc_peer *get_self(struct net *net, int bearer_id)
196{
197 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
198
199 return mon->self;
200}
201
202static inline bool tipc_mon_is_active(struct net *net, struct tipc_monitor *mon)
203{
204 struct tipc_net *tn = tipc_net(net);
205
206 return mon->peer_cnt > tn->mon_threshold;
207}
208
209/* mon_identify_lost_members() : - identify amd mark potentially lost members
210 */
211static void mon_identify_lost_members(struct tipc_peer *peer,
212 struct tipc_mon_domain *dom_bef,
213 int applied_bef)
214{
215 struct tipc_peer *member = peer;
216 struct tipc_mon_domain *dom_aft = peer->domain;
217 int applied_aft = peer->applied;
218 int i;
219
220 for (i = 0; i < applied_bef; i++) {
221 member = peer_nxt(member);
222
223 /* Do nothing if self or peer already see member as down */
224 if (!member->is_up || !map_get(dom_bef->up_map, i))
225 continue;
226
227 /* Loss of local node must be detected by active probing */
228 if (member->is_local)
229 continue;
230
231 /* Start probing if member was removed from applied domain */
232 if (!applied_aft || (applied_aft < i)) {
233 member->down_cnt = 1;
234 continue;
235 }
236
237 /* Member loss is confirmed if it is still in applied domain */
238 if (!map_get(dom_aft->up_map, i))
239 member->down_cnt++;
240 }
241}
242
243/* mon_apply_domain() : match a peer's domain record against monitor list
244 */
245static void mon_apply_domain(struct tipc_monitor *mon,
246 struct tipc_peer *peer)
247{
248 struct tipc_mon_domain *dom = peer->domain;
249 struct tipc_peer *member;
250 u32 addr;
251 int i;
252
253 if (!dom || !peer->is_up)
254 return;
255
256 /* Scan across domain members and match against monitor list */
257 peer->applied = 0;
258 member = peer_nxt(peer);
259 for (i = 0; i < dom->member_cnt; i++) {
260 addr = dom->members[i];
261 if (addr != member->addr)
262 return;
263 peer->applied++;
264 member = peer_nxt(member);
265 }
266}
267
268/* mon_update_local_domain() : update after peer addition/removal/up/down
269 */
270static void mon_update_local_domain(struct tipc_monitor *mon)
271{
272 struct tipc_peer *self = mon->self;
273 struct tipc_mon_domain *cache = &mon->cache;
274 struct tipc_mon_domain *dom = self->domain;
275 struct tipc_peer *peer = self;
276 u64 prev_up_map = dom->up_map;
277 u16 member_cnt, i;
278 bool diff;
279
280 /* Update local domain size based on current size of cluster */
281 member_cnt = dom_size(mon->peer_cnt) - 1;
282 self->applied = member_cnt;
283
284 /* Update native and cached outgoing local domain records */
285 dom->len = dom_rec_len(dom, member_cnt);
286 diff = dom->member_cnt != member_cnt;
287 dom->member_cnt = member_cnt;
288 for (i = 0; i < member_cnt; i++) {
289 peer = peer_nxt(peer);
290 diff |= dom->members[i] != peer->addr;
291 dom->members[i] = peer->addr;
292 map_set(&dom->up_map, i, peer->is_up);
293 cache->members[i] = mon_cpu_to_le32(peer->addr);
294 }
295 diff |= dom->up_map != prev_up_map;
296 if (!diff)
297 return;
298 dom->gen = ++mon->dom_gen;
299 cache->len = mon_cpu_to_le16(dom->len);
300 cache->gen = mon_cpu_to_le16(dom->gen);
301 cache->member_cnt = mon_cpu_to_le16(member_cnt);
302 cache->up_map = mon_cpu_to_le64(dom->up_map);
303 mon_apply_domain(mon, self);
304}
305
306/* mon_update_neighbors() : update preceding neighbors of added/removed peer
307 */
308static void mon_update_neighbors(struct tipc_monitor *mon,
309 struct tipc_peer *peer)
310{
311 int dz, i;
312
313 dz = dom_size(mon->peer_cnt);
314 for (i = 0; i < dz; i++) {
315 mon_apply_domain(mon, peer);
316 peer = peer_prev(peer);
317 }
318}
319
320/* mon_assign_roles() : reassign peer roles after a network change
321 * The monitor list is consistent at this stage; i.e., each peer is monitoring
322 * a set of domain members as matched between domain record and the monitor list
323 */
324static void mon_assign_roles(struct tipc_monitor *mon, struct tipc_peer *head)
325{
326 struct tipc_peer *peer = peer_nxt(head);
327 struct tipc_peer *self = mon->self;
328 int i = 0;
329
330 for (; peer != self; peer = peer_nxt(peer)) {
331 peer->is_local = false;
332
333 /* Update domain member */
334 if (i++ < head->applied) {
335 peer->is_head = false;
336 if (head == self)
337 peer->is_local = true;
338 continue;
339 }
340 /* Assign next domain head */
341 if (!peer->is_up)
342 continue;
343 if (peer->is_head)
344 break;
345 head = peer;
346 head->is_head = true;
347 i = 0;
348 }
349 mon->list_gen++;
350}
351
352void tipc_mon_remove_peer(struct net *net, u32 addr, int bearer_id)
353{
354 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
355 struct tipc_peer *self;
356 struct tipc_peer *peer, *prev, *head;
357
358 if (!mon)
359 return;
360
361 self = get_self(net, bearer_id);
362 write_lock_bh(&mon->lock);
363 peer = get_peer(mon, addr);
364 if (!peer)
365 goto exit;
366 prev = peer_prev(peer);
367 list_del(&peer->list);
368 hlist_del(&peer->hash);
369 kfree(peer->domain);
370 kfree(peer);
371 mon->peer_cnt--;
372 head = peer_head(prev);
373 if (head == self)
374 mon_update_local_domain(mon);
375 mon_update_neighbors(mon, prev);
376
377 /* Revert to full-mesh monitoring if we reach threshold */
378 if (!tipc_mon_is_active(net, mon)) {
379 list_for_each_entry(peer, &self->list, list) {
380 kfree(peer->domain);
381 peer->domain = NULL;
382 peer->applied = 0;
383 }
384 }
385 mon_assign_roles(mon, head);
386exit:
387 write_unlock_bh(&mon->lock);
388}
389
390static bool tipc_mon_add_peer(struct tipc_monitor *mon, u32 addr,
391 struct tipc_peer **peer)
392{
393 struct tipc_peer *self = mon->self;
394 struct tipc_peer *cur, *prev, *p;
395
396 p = kzalloc(sizeof(*p), GFP_ATOMIC);
397 *peer = p;
398 if (!p)
399 return false;
400 p->addr = addr;
401
402 /* Add new peer to lookup list */
403 INIT_LIST_HEAD(&p->list);
404 hlist_add_head(&p->hash, &mon->peers[tipc_hashfn(addr)]);
405
406 /* Sort new peer into iterator list, in ascending circular order */
407 prev = self;
408 list_for_each_entry(cur, &self->list, list) {
409 if ((addr > prev->addr) && (addr < cur->addr))
410 break;
411 if (((addr < cur->addr) || (addr > prev->addr)) &&
412 (prev->addr > cur->addr))
413 break;
414 prev = cur;
415 }
416 list_add_tail(&p->list, &cur->list);
417 mon->peer_cnt++;
418 mon_update_neighbors(mon, p);
419 return true;
420}
421
422void tipc_mon_peer_up(struct net *net, u32 addr, int bearer_id)
423{
424 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
425 struct tipc_peer *self = get_self(net, bearer_id);
426 struct tipc_peer *peer, *head;
427
428 write_lock_bh(&mon->lock);
429 peer = get_peer(mon, addr);
430 if (!peer && !tipc_mon_add_peer(mon, addr, &peer))
431 goto exit;
432 peer->is_up = true;
433 head = peer_head(peer);
434 if (head == self)
435 mon_update_local_domain(mon);
436 mon_assign_roles(mon, head);
437exit:
438 write_unlock_bh(&mon->lock);
439}
440
441void tipc_mon_peer_down(struct net *net, u32 addr, int bearer_id)
442{
443 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
444 struct tipc_peer *self;
445 struct tipc_peer *peer, *head;
446 struct tipc_mon_domain *dom;
447 int applied;
448
449 if (!mon)
450 return;
451
452 self = get_self(net, bearer_id);
453 write_lock_bh(&mon->lock);
454 peer = get_peer(mon, addr);
455 if (!peer) {
456 pr_warn("Mon: unknown link %x/%u DOWN\n", addr, bearer_id);
457 goto exit;
458 }
459 applied = peer->applied;
460 peer->applied = 0;
461 dom = peer->domain;
462 peer->domain = NULL;
463 if (peer->is_head)
464 mon_identify_lost_members(peer, dom, applied);
465 kfree(dom);
466 peer->is_up = false;
467 peer->is_head = false;
468 peer->is_local = false;
469 peer->down_cnt = 0;
470 head = peer_head(peer);
471 if (head == self)
472 mon_update_local_domain(mon);
473 mon_assign_roles(mon, head);
474exit:
475 write_unlock_bh(&mon->lock);
476}
477
478/* tipc_mon_rcv - process monitor domain event message
479 */
480void tipc_mon_rcv(struct net *net, void *data, u16 dlen, u32 addr,
481 struct tipc_mon_state *state, int bearer_id)
482{
483 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
484 struct tipc_mon_domain *arrv_dom = data;
485 struct tipc_mon_domain dom_bef;
486 struct tipc_mon_domain *dom;
487 struct tipc_peer *peer;
488 u16 new_member_cnt = mon_le16_to_cpu(arrv_dom->member_cnt);
489 int new_dlen = dom_rec_len(arrv_dom, new_member_cnt);
490 u16 new_gen = mon_le16_to_cpu(arrv_dom->gen);
491 u16 acked_gen = mon_le16_to_cpu(arrv_dom->ack_gen);
492 u16 arrv_dlen = mon_le16_to_cpu(arrv_dom->len);
493 bool probing = state->probing;
494 int i, applied_bef;
495
496 state->probing = false;
497
498 /* Sanity check received domain record */
499 if (new_member_cnt > MAX_MON_DOMAIN)
500 return;
501 if (dlen < dom_rec_len(arrv_dom, 0))
502 return;
503 if (dlen != dom_rec_len(arrv_dom, new_member_cnt))
504 return;
505 if (dlen < new_dlen || arrv_dlen != new_dlen)
506 return;
507
508 /* Synch generation numbers with peer if link just came up */
509 if (!state->synched) {
510 state->peer_gen = new_gen - 1;
511 state->acked_gen = acked_gen;
512 state->synched = true;
513 }
514
515 if (more(acked_gen, state->acked_gen))
516 state->acked_gen = acked_gen;
517
518 /* Drop duplicate unless we are waiting for a probe response */
519 if (!more(new_gen, state->peer_gen) && !probing)
520 return;
521
522 write_lock_bh(&mon->lock);
523 peer = get_peer(mon, addr);
524 if (!peer || !peer->is_up)
525 goto exit;
526
527 /* Peer is confirmed, stop any ongoing probing */
528 peer->down_cnt = 0;
529
530 /* Task is done for duplicate record */
531 if (!more(new_gen, state->peer_gen))
532 goto exit;
533
534 state->peer_gen = new_gen;
535
536 /* Cache current domain record for later use */
537 dom_bef.member_cnt = 0;
538 dom = peer->domain;
539 if (dom)
540 memcpy(&dom_bef, dom, dom->len);
541
542 /* Transform and store received domain record */
543 if (!dom || (dom->len < new_dlen)) {
544 kfree(dom);
545 dom = kmalloc(new_dlen, GFP_ATOMIC);
546 peer->domain = dom;
547 if (!dom)
548 goto exit;
549 }
550 dom->len = new_dlen;
551 dom->gen = new_gen;
552 dom->member_cnt = new_member_cnt;
553 dom->up_map = mon_le64_to_cpu(arrv_dom->up_map);
554 for (i = 0; i < new_member_cnt; i++)
555 dom->members[i] = mon_le32_to_cpu(arrv_dom->members[i]);
556
557 /* Update peers affected by this domain record */
558 applied_bef = peer->applied;
559 mon_apply_domain(mon, peer);
560 mon_identify_lost_members(peer, &dom_bef, applied_bef);
561 mon_assign_roles(mon, peer_head(peer));
562exit:
563 write_unlock_bh(&mon->lock);
564}
565
566void tipc_mon_prep(struct net *net, void *data, int *dlen,
567 struct tipc_mon_state *state, int bearer_id)
568{
569 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
570 struct tipc_mon_domain *dom = data;
571 u16 gen = mon->dom_gen;
572 u16 len;
573
574 /* Send invalid record if not active */
575 if (!tipc_mon_is_active(net, mon)) {
576 dom->len = 0;
577 return;
578 }
579
580 /* Send only a dummy record with ack if peer has acked our last sent */
581 if (likely(state->acked_gen == gen)) {
582 len = dom_rec_len(dom, 0);
583 *dlen = len;
584 dom->len = mon_cpu_to_le16(len);
585 dom->gen = mon_cpu_to_le16(gen);
586 dom->ack_gen = mon_cpu_to_le16(state->peer_gen);
587 dom->member_cnt = 0;
588 return;
589 }
590 /* Send the full record */
591 read_lock_bh(&mon->lock);
592 len = mon_le16_to_cpu(mon->cache.len);
593 *dlen = len;
594 memcpy(data, &mon->cache, len);
595 read_unlock_bh(&mon->lock);
596 dom->ack_gen = mon_cpu_to_le16(state->peer_gen);
597}
598
599void tipc_mon_get_state(struct net *net, u32 addr,
600 struct tipc_mon_state *state,
601 int bearer_id)
602{
603 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
604 struct tipc_peer *peer;
605
606 if (!tipc_mon_is_active(net, mon)) {
607 state->probing = false;
608 state->monitoring = true;
609 return;
610 }
611
612 /* Used cached state if table has not changed */
613 if (!state->probing &&
614 (state->list_gen == mon->list_gen) &&
615 (state->acked_gen == mon->dom_gen))
616 return;
617
618 read_lock_bh(&mon->lock);
619 peer = get_peer(mon, addr);
620 if (peer) {
621 state->probing = state->acked_gen != mon->dom_gen;
622 state->probing |= peer->down_cnt;
623 state->reset |= peer->down_cnt >= MAX_PEER_DOWN_EVENTS;
624 state->monitoring = peer->is_local;
625 state->monitoring |= peer->is_head;
626 state->list_gen = mon->list_gen;
627 }
628 read_unlock_bh(&mon->lock);
629}
630
631static void mon_timeout(struct timer_list *t)
632{
633 struct tipc_monitor *mon = from_timer(mon, t, timer);
634 struct tipc_peer *self;
635 int best_member_cnt = dom_size(mon->peer_cnt) - 1;
636
637 write_lock_bh(&mon->lock);
638 self = mon->self;
639 if (self && (best_member_cnt != self->applied)) {
640 mon_update_local_domain(mon);
641 mon_assign_roles(mon, self);
642 }
643 write_unlock_bh(&mon->lock);
644 mod_timer(&mon->timer, jiffies + mon->timer_intv);
645}
646
647int tipc_mon_create(struct net *net, int bearer_id)
648{
649 struct tipc_net *tn = tipc_net(net);
650 struct tipc_monitor *mon;
651 struct tipc_peer *self;
652 struct tipc_mon_domain *dom;
653
654 if (tn->monitors[bearer_id])
655 return 0;
656
657 mon = kzalloc(sizeof(*mon), GFP_ATOMIC);
658 self = kzalloc(sizeof(*self), GFP_ATOMIC);
659 dom = kzalloc(sizeof(*dom), GFP_ATOMIC);
660 if (!mon || !self || !dom) {
661 kfree(mon);
662 kfree(self);
663 kfree(dom);
664 return -ENOMEM;
665 }
666 tn->monitors[bearer_id] = mon;
667 rwlock_init(&mon->lock);
668 mon->net = net;
669 mon->peer_cnt = 1;
670 mon->self = self;
671 self->domain = dom;
672 self->addr = tipc_own_addr(net);
673 self->is_up = true;
674 self->is_head = true;
675 INIT_LIST_HEAD(&self->list);
676 timer_setup(&mon->timer, mon_timeout, 0);
677 mon->timer_intv = msecs_to_jiffies(MON_TIMEOUT + (tn->random & 0xffff));
678 mod_timer(&mon->timer, jiffies + mon->timer_intv);
679 return 0;
680}
681
682void tipc_mon_delete(struct net *net, int bearer_id)
683{
684 struct tipc_net *tn = tipc_net(net);
685 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
686 struct tipc_peer *self;
687 struct tipc_peer *peer, *tmp;
688
689 if (!mon)
690 return;
691
692 self = get_self(net, bearer_id);
693 write_lock_bh(&mon->lock);
694 tn->monitors[bearer_id] = NULL;
695 list_for_each_entry_safe(peer, tmp, &self->list, list) {
696 list_del(&peer->list);
697 hlist_del(&peer->hash);
698 kfree(peer->domain);
699 kfree(peer);
700 }
701 mon->self = NULL;
702 write_unlock_bh(&mon->lock);
703 timer_shutdown_sync(&mon->timer);
704 kfree(self->domain);
705 kfree(self);
706 kfree(mon);
707}
708
709void tipc_mon_reinit_self(struct net *net)
710{
711 struct tipc_monitor *mon;
712 int bearer_id;
713
714 for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
715 mon = tipc_monitor(net, bearer_id);
716 if (!mon)
717 continue;
718 write_lock_bh(&mon->lock);
719 mon->self->addr = tipc_own_addr(net);
720 write_unlock_bh(&mon->lock);
721 }
722}
723
724int tipc_nl_monitor_set_threshold(struct net *net, u32 cluster_size)
725{
726 struct tipc_net *tn = tipc_net(net);
727
728 if (cluster_size > TIPC_CLUSTER_SIZE)
729 return -EINVAL;
730
731 tn->mon_threshold = cluster_size;
732
733 return 0;
734}
735
736int tipc_nl_monitor_get_threshold(struct net *net)
737{
738 struct tipc_net *tn = tipc_net(net);
739
740 return tn->mon_threshold;
741}
742
743static int __tipc_nl_add_monitor_peer(struct tipc_peer *peer,
744 struct tipc_nl_msg *msg)
745{
746 struct tipc_mon_domain *dom = peer->domain;
747 struct nlattr *attrs;
748 void *hdr;
749
750 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
751 NLM_F_MULTI, TIPC_NL_MON_PEER_GET);
752 if (!hdr)
753 return -EMSGSIZE;
754
755 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON_PEER);
756 if (!attrs)
757 goto msg_full;
758
759 if (nla_put_u32(msg->skb, TIPC_NLA_MON_PEER_ADDR, peer->addr))
760 goto attr_msg_full;
761 if (nla_put_u32(msg->skb, TIPC_NLA_MON_PEER_APPLIED, peer->applied))
762 goto attr_msg_full;
763
764 if (peer->is_up)
765 if (nla_put_flag(msg->skb, TIPC_NLA_MON_PEER_UP))
766 goto attr_msg_full;
767 if (peer->is_local)
768 if (nla_put_flag(msg->skb, TIPC_NLA_MON_PEER_LOCAL))
769 goto attr_msg_full;
770 if (peer->is_head)
771 if (nla_put_flag(msg->skb, TIPC_NLA_MON_PEER_HEAD))
772 goto attr_msg_full;
773
774 if (dom) {
775 if (nla_put_u32(msg->skb, TIPC_NLA_MON_PEER_DOMGEN, dom->gen))
776 goto attr_msg_full;
777 if (nla_put_u64_64bit(msg->skb, TIPC_NLA_MON_PEER_UPMAP,
778 dom->up_map, TIPC_NLA_MON_PEER_PAD))
779 goto attr_msg_full;
780 if (nla_put(msg->skb, TIPC_NLA_MON_PEER_MEMBERS,
781 dom->member_cnt * sizeof(u32), &dom->members))
782 goto attr_msg_full;
783 }
784
785 nla_nest_end(msg->skb, attrs);
786 genlmsg_end(msg->skb, hdr);
787 return 0;
788
789attr_msg_full:
790 nla_nest_cancel(msg->skb, attrs);
791msg_full:
792 genlmsg_cancel(msg->skb, hdr);
793
794 return -EMSGSIZE;
795}
796
797int tipc_nl_add_monitor_peer(struct net *net, struct tipc_nl_msg *msg,
798 u32 bearer_id, u32 *prev_node)
799{
800 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
801 struct tipc_peer *peer;
802
803 if (!mon)
804 return -EINVAL;
805
806 read_lock_bh(&mon->lock);
807 peer = mon->self;
808 do {
809 if (*prev_node) {
810 if (peer->addr == *prev_node)
811 *prev_node = 0;
812 else
813 continue;
814 }
815 if (__tipc_nl_add_monitor_peer(peer, msg)) {
816 *prev_node = peer->addr;
817 read_unlock_bh(&mon->lock);
818 return -EMSGSIZE;
819 }
820 } while ((peer = peer_nxt(peer)) != mon->self);
821 read_unlock_bh(&mon->lock);
822
823 return 0;
824}
825
826int __tipc_nl_add_monitor(struct net *net, struct tipc_nl_msg *msg,
827 u32 bearer_id)
828{
829 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
830 char bearer_name[TIPC_MAX_BEARER_NAME];
831 struct nlattr *attrs;
832 void *hdr;
833 int ret;
834
835 ret = tipc_bearer_get_name(net, bearer_name, bearer_id);
836 if (ret || !mon)
837 return 0;
838
839 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
840 NLM_F_MULTI, TIPC_NL_MON_GET);
841 if (!hdr)
842 return -EMSGSIZE;
843
844 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON);
845 if (!attrs)
846 goto msg_full;
847
848 read_lock_bh(&mon->lock);
849 if (nla_put_u32(msg->skb, TIPC_NLA_MON_REF, bearer_id))
850 goto attr_msg_full;
851 if (tipc_mon_is_active(net, mon))
852 if (nla_put_flag(msg->skb, TIPC_NLA_MON_ACTIVE))
853 goto attr_msg_full;
854 if (nla_put_string(msg->skb, TIPC_NLA_MON_BEARER_NAME, bearer_name))
855 goto attr_msg_full;
856 if (nla_put_u32(msg->skb, TIPC_NLA_MON_PEERCNT, mon->peer_cnt))
857 goto attr_msg_full;
858 if (nla_put_u32(msg->skb, TIPC_NLA_MON_LISTGEN, mon->list_gen))
859 goto attr_msg_full;
860
861 read_unlock_bh(&mon->lock);
862 nla_nest_end(msg->skb, attrs);
863 genlmsg_end(msg->skb, hdr);
864
865 return 0;
866
867attr_msg_full:
868 read_unlock_bh(&mon->lock);
869 nla_nest_cancel(msg->skb, attrs);
870msg_full:
871 genlmsg_cancel(msg->skb, hdr);
872
873 return -EMSGSIZE;
874}
1/*
2 * net/tipc/monitor.c
3 *
4 * Copyright (c) 2016, Ericsson AB
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the names of the copyright holders nor the names of its
16 * contributors may be used to endorse or promote products derived from
17 * this software without specific prior written permission.
18 *
19 * Alternatively, this software may be distributed under the terms of the
20 * GNU General Public License ("GPL") version 2 as published by the Free
21 * Software Foundation.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
24 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
27 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33 * POSSIBILITY OF SUCH DAMAGE.
34 */
35
36#include <net/genetlink.h>
37#include "core.h"
38#include "addr.h"
39#include "monitor.h"
40#include "bearer.h"
41
42#define MAX_MON_DOMAIN 64
43#define MON_TIMEOUT 120000
44#define MAX_PEER_DOWN_EVENTS 4
45
46/* struct tipc_mon_domain: domain record to be transferred between peers
47 * @len: actual size of domain record
48 * @gen: current generation of sender's domain
49 * @ack_gen: most recent generation of self's domain acked by peer
50 * @member_cnt: number of domain member nodes described in this record
51 * @up_map: bit map indicating which of the members the sender considers up
52 * @members: identity of the domain members
53 */
54struct tipc_mon_domain {
55 u16 len;
56 u16 gen;
57 u16 ack_gen;
58 u16 member_cnt;
59 u64 up_map;
60 u32 members[MAX_MON_DOMAIN];
61};
62
63/* struct tipc_peer: state of a peer node and its domain
64 * @addr: tipc node identity of peer
65 * @head_map: shows which other nodes currently consider peer 'up'
66 * @domain: most recent domain record from peer
67 * @hash: position in hashed lookup list
68 * @list: position in linked list, in circular ascending order by 'addr'
69 * @applied: number of reported domain members applied on this monitor list
70 * @is_up: peer is up as seen from this node
71 * @is_head: peer is assigned domain head as seen from this node
72 * @is_local: peer is in local domain and should be continuously monitored
73 * @down_cnt: - numbers of other peers which have reported this on lost
74 */
75struct tipc_peer {
76 u32 addr;
77 struct tipc_mon_domain *domain;
78 struct hlist_node hash;
79 struct list_head list;
80 u8 applied;
81 u8 down_cnt;
82 bool is_up;
83 bool is_head;
84 bool is_local;
85};
86
87struct tipc_monitor {
88 struct hlist_head peers[NODE_HTABLE_SIZE];
89 int peer_cnt;
90 struct tipc_peer *self;
91 rwlock_t lock;
92 struct tipc_mon_domain cache;
93 u16 list_gen;
94 u16 dom_gen;
95 struct net *net;
96 struct timer_list timer;
97 unsigned long timer_intv;
98};
99
100static struct tipc_monitor *tipc_monitor(struct net *net, int bearer_id)
101{
102 return tipc_net(net)->monitors[bearer_id];
103}
104
105const int tipc_max_domain_size = sizeof(struct tipc_mon_domain);
106
107/* dom_rec_len(): actual length of domain record for transport
108 */
109static int dom_rec_len(struct tipc_mon_domain *dom, u16 mcnt)
110{
111 return ((void *)&dom->members - (void *)dom) + (mcnt * sizeof(u32));
112}
113
114/* dom_size() : calculate size of own domain based on number of peers
115 */
116static int dom_size(int peers)
117{
118 int i = 0;
119
120 while ((i * i) < peers)
121 i++;
122 return i < MAX_MON_DOMAIN ? i : MAX_MON_DOMAIN;
123}
124
125static void map_set(u64 *up_map, int i, unsigned int v)
126{
127 *up_map &= ~(1ULL << i);
128 *up_map |= ((u64)v << i);
129}
130
131static int map_get(u64 up_map, int i)
132{
133 return (up_map & (1 << i)) >> i;
134}
135
136static struct tipc_peer *peer_prev(struct tipc_peer *peer)
137{
138 return list_last_entry(&peer->list, struct tipc_peer, list);
139}
140
141static struct tipc_peer *peer_nxt(struct tipc_peer *peer)
142{
143 return list_first_entry(&peer->list, struct tipc_peer, list);
144}
145
146static struct tipc_peer *peer_head(struct tipc_peer *peer)
147{
148 while (!peer->is_head)
149 peer = peer_prev(peer);
150 return peer;
151}
152
153static struct tipc_peer *get_peer(struct tipc_monitor *mon, u32 addr)
154{
155 struct tipc_peer *peer;
156 unsigned int thash = tipc_hashfn(addr);
157
158 hlist_for_each_entry(peer, &mon->peers[thash], hash) {
159 if (peer->addr == addr)
160 return peer;
161 }
162 return NULL;
163}
164
165static struct tipc_peer *get_self(struct net *net, int bearer_id)
166{
167 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
168
169 return mon->self;
170}
171
172static inline bool tipc_mon_is_active(struct net *net, struct tipc_monitor *mon)
173{
174 struct tipc_net *tn = tipc_net(net);
175
176 return mon->peer_cnt > tn->mon_threshold;
177}
178
179/* mon_identify_lost_members() : - identify amd mark potentially lost members
180 */
181static void mon_identify_lost_members(struct tipc_peer *peer,
182 struct tipc_mon_domain *dom_bef,
183 int applied_bef)
184{
185 struct tipc_peer *member = peer;
186 struct tipc_mon_domain *dom_aft = peer->domain;
187 int applied_aft = peer->applied;
188 int i;
189
190 for (i = 0; i < applied_bef; i++) {
191 member = peer_nxt(member);
192
193 /* Do nothing if self or peer already see member as down */
194 if (!member->is_up || !map_get(dom_bef->up_map, i))
195 continue;
196
197 /* Loss of local node must be detected by active probing */
198 if (member->is_local)
199 continue;
200
201 /* Start probing if member was removed from applied domain */
202 if (!applied_aft || (applied_aft < i)) {
203 member->down_cnt = 1;
204 continue;
205 }
206
207 /* Member loss is confirmed if it is still in applied domain */
208 if (!map_get(dom_aft->up_map, i))
209 member->down_cnt++;
210 }
211}
212
213/* mon_apply_domain() : match a peer's domain record against monitor list
214 */
215static void mon_apply_domain(struct tipc_monitor *mon,
216 struct tipc_peer *peer)
217{
218 struct tipc_mon_domain *dom = peer->domain;
219 struct tipc_peer *member;
220 u32 addr;
221 int i;
222
223 if (!dom || !peer->is_up)
224 return;
225
226 /* Scan across domain members and match against monitor list */
227 peer->applied = 0;
228 member = peer_nxt(peer);
229 for (i = 0; i < dom->member_cnt; i++) {
230 addr = dom->members[i];
231 if (addr != member->addr)
232 return;
233 peer->applied++;
234 member = peer_nxt(member);
235 }
236}
237
238/* mon_update_local_domain() : update after peer addition/removal/up/down
239 */
240static void mon_update_local_domain(struct tipc_monitor *mon)
241{
242 struct tipc_peer *self = mon->self;
243 struct tipc_mon_domain *cache = &mon->cache;
244 struct tipc_mon_domain *dom = self->domain;
245 struct tipc_peer *peer = self;
246 u64 prev_up_map = dom->up_map;
247 u16 member_cnt, i;
248 bool diff;
249
250 /* Update local domain size based on current size of cluster */
251 member_cnt = dom_size(mon->peer_cnt) - 1;
252 self->applied = member_cnt;
253
254 /* Update native and cached outgoing local domain records */
255 dom->len = dom_rec_len(dom, member_cnt);
256 diff = dom->member_cnt != member_cnt;
257 dom->member_cnt = member_cnt;
258 for (i = 0; i < member_cnt; i++) {
259 peer = peer_nxt(peer);
260 diff |= dom->members[i] != peer->addr;
261 dom->members[i] = peer->addr;
262 map_set(&dom->up_map, i, peer->is_up);
263 cache->members[i] = htonl(peer->addr);
264 }
265 diff |= dom->up_map != prev_up_map;
266 if (!diff)
267 return;
268 dom->gen = ++mon->dom_gen;
269 cache->len = htons(dom->len);
270 cache->gen = htons(dom->gen);
271 cache->member_cnt = htons(member_cnt);
272 cache->up_map = cpu_to_be64(dom->up_map);
273 mon_apply_domain(mon, self);
274}
275
276/* mon_update_neighbors() : update preceding neighbors of added/removed peer
277 */
278static void mon_update_neighbors(struct tipc_monitor *mon,
279 struct tipc_peer *peer)
280{
281 int dz, i;
282
283 dz = dom_size(mon->peer_cnt);
284 for (i = 0; i < dz; i++) {
285 mon_apply_domain(mon, peer);
286 peer = peer_prev(peer);
287 }
288}
289
290/* mon_assign_roles() : reassign peer roles after a network change
291 * The monitor list is consistent at this stage; i.e., each peer is monitoring
292 * a set of domain members as matched between domain record and the monitor list
293 */
294static void mon_assign_roles(struct tipc_monitor *mon, struct tipc_peer *head)
295{
296 struct tipc_peer *peer = peer_nxt(head);
297 struct tipc_peer *self = mon->self;
298 int i = 0;
299
300 for (; peer != self; peer = peer_nxt(peer)) {
301 peer->is_local = false;
302
303 /* Update domain member */
304 if (i++ < head->applied) {
305 peer->is_head = false;
306 if (head == self)
307 peer->is_local = true;
308 continue;
309 }
310 /* Assign next domain head */
311 if (!peer->is_up)
312 continue;
313 if (peer->is_head)
314 break;
315 head = peer;
316 head->is_head = true;
317 i = 0;
318 }
319 mon->list_gen++;
320}
321
322void tipc_mon_remove_peer(struct net *net, u32 addr, int bearer_id)
323{
324 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
325 struct tipc_peer *self = get_self(net, bearer_id);
326 struct tipc_peer *peer, *prev, *head;
327
328 write_lock_bh(&mon->lock);
329 peer = get_peer(mon, addr);
330 if (!peer)
331 goto exit;
332 prev = peer_prev(peer);
333 list_del(&peer->list);
334 hlist_del(&peer->hash);
335 kfree(peer->domain);
336 kfree(peer);
337 mon->peer_cnt--;
338 head = peer_head(prev);
339 if (head == self)
340 mon_update_local_domain(mon);
341 mon_update_neighbors(mon, prev);
342
343 /* Revert to full-mesh monitoring if we reach threshold */
344 if (!tipc_mon_is_active(net, mon)) {
345 list_for_each_entry(peer, &self->list, list) {
346 kfree(peer->domain);
347 peer->domain = NULL;
348 peer->applied = 0;
349 }
350 }
351 mon_assign_roles(mon, head);
352exit:
353 write_unlock_bh(&mon->lock);
354}
355
356static bool tipc_mon_add_peer(struct tipc_monitor *mon, u32 addr,
357 struct tipc_peer **peer)
358{
359 struct tipc_peer *self = mon->self;
360 struct tipc_peer *cur, *prev, *p;
361
362 p = kzalloc(sizeof(*p), GFP_ATOMIC);
363 *peer = p;
364 if (!p)
365 return false;
366 p->addr = addr;
367
368 /* Add new peer to lookup list */
369 INIT_LIST_HEAD(&p->list);
370 hlist_add_head(&p->hash, &mon->peers[tipc_hashfn(addr)]);
371
372 /* Sort new peer into iterator list, in ascending circular order */
373 prev = self;
374 list_for_each_entry(cur, &self->list, list) {
375 if ((addr > prev->addr) && (addr < cur->addr))
376 break;
377 if (((addr < cur->addr) || (addr > prev->addr)) &&
378 (prev->addr > cur->addr))
379 break;
380 prev = cur;
381 }
382 list_add_tail(&p->list, &cur->list);
383 mon->peer_cnt++;
384 mon_update_neighbors(mon, p);
385 return true;
386}
387
388void tipc_mon_peer_up(struct net *net, u32 addr, int bearer_id)
389{
390 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
391 struct tipc_peer *self = get_self(net, bearer_id);
392 struct tipc_peer *peer, *head;
393
394 write_lock_bh(&mon->lock);
395 peer = get_peer(mon, addr);
396 if (!peer && !tipc_mon_add_peer(mon, addr, &peer))
397 goto exit;
398 peer->is_up = true;
399 head = peer_head(peer);
400 if (head == self)
401 mon_update_local_domain(mon);
402 mon_assign_roles(mon, head);
403exit:
404 write_unlock_bh(&mon->lock);
405}
406
407void tipc_mon_peer_down(struct net *net, u32 addr, int bearer_id)
408{
409 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
410 struct tipc_peer *self = get_self(net, bearer_id);
411 struct tipc_peer *peer, *head;
412 struct tipc_mon_domain *dom;
413 int applied;
414
415 write_lock_bh(&mon->lock);
416 peer = get_peer(mon, addr);
417 if (!peer) {
418 pr_warn("Mon: unknown link %x/%u DOWN\n", addr, bearer_id);
419 goto exit;
420 }
421 applied = peer->applied;
422 peer->applied = 0;
423 dom = peer->domain;
424 peer->domain = NULL;
425 if (peer->is_head)
426 mon_identify_lost_members(peer, dom, applied);
427 kfree(dom);
428 peer->is_up = false;
429 peer->is_head = false;
430 peer->is_local = false;
431 peer->down_cnt = 0;
432 head = peer_head(peer);
433 if (head == self)
434 mon_update_local_domain(mon);
435 mon_assign_roles(mon, head);
436exit:
437 write_unlock_bh(&mon->lock);
438}
439
440/* tipc_mon_rcv - process monitor domain event message
441 */
442void tipc_mon_rcv(struct net *net, void *data, u16 dlen, u32 addr,
443 struct tipc_mon_state *state, int bearer_id)
444{
445 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
446 struct tipc_mon_domain *arrv_dom = data;
447 struct tipc_mon_domain dom_bef;
448 struct tipc_mon_domain *dom;
449 struct tipc_peer *peer;
450 u16 new_member_cnt = ntohs(arrv_dom->member_cnt);
451 int new_dlen = dom_rec_len(arrv_dom, new_member_cnt);
452 u16 new_gen = ntohs(arrv_dom->gen);
453 u16 acked_gen = ntohs(arrv_dom->ack_gen);
454 bool probing = state->probing;
455 int i, applied_bef;
456
457 state->probing = false;
458
459 /* Sanity check received domain record */
460 if (dlen < dom_rec_len(arrv_dom, 0))
461 return;
462 if (dlen != dom_rec_len(arrv_dom, new_member_cnt))
463 return;
464 if ((dlen < new_dlen) || ntohs(arrv_dom->len) != new_dlen)
465 return;
466
467 /* Synch generation numbers with peer if link just came up */
468 if (!state->synched) {
469 state->peer_gen = new_gen - 1;
470 state->acked_gen = acked_gen;
471 state->synched = true;
472 }
473
474 if (more(acked_gen, state->acked_gen))
475 state->acked_gen = acked_gen;
476
477 /* Drop duplicate unless we are waiting for a probe response */
478 if (!more(new_gen, state->peer_gen) && !probing)
479 return;
480
481 write_lock_bh(&mon->lock);
482 peer = get_peer(mon, addr);
483 if (!peer || !peer->is_up)
484 goto exit;
485
486 /* Peer is confirmed, stop any ongoing probing */
487 peer->down_cnt = 0;
488
489 /* Task is done for duplicate record */
490 if (!more(new_gen, state->peer_gen))
491 goto exit;
492
493 state->peer_gen = new_gen;
494
495 /* Cache current domain record for later use */
496 dom_bef.member_cnt = 0;
497 dom = peer->domain;
498 if (dom)
499 memcpy(&dom_bef, dom, dom->len);
500
501 /* Transform and store received domain record */
502 if (!dom || (dom->len < new_dlen)) {
503 kfree(dom);
504 dom = kmalloc(new_dlen, GFP_ATOMIC);
505 peer->domain = dom;
506 if (!dom)
507 goto exit;
508 }
509 dom->len = new_dlen;
510 dom->gen = new_gen;
511 dom->member_cnt = new_member_cnt;
512 dom->up_map = be64_to_cpu(arrv_dom->up_map);
513 for (i = 0; i < new_member_cnt; i++)
514 dom->members[i] = ntohl(arrv_dom->members[i]);
515
516 /* Update peers affected by this domain record */
517 applied_bef = peer->applied;
518 mon_apply_domain(mon, peer);
519 mon_identify_lost_members(peer, &dom_bef, applied_bef);
520 mon_assign_roles(mon, peer_head(peer));
521exit:
522 write_unlock_bh(&mon->lock);
523}
524
525void tipc_mon_prep(struct net *net, void *data, int *dlen,
526 struct tipc_mon_state *state, int bearer_id)
527{
528 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
529 struct tipc_mon_domain *dom = data;
530 u16 gen = mon->dom_gen;
531 u16 len;
532
533 /* Send invalid record if not active */
534 if (!tipc_mon_is_active(net, mon)) {
535 dom->len = 0;
536 return;
537 }
538
539 /* Send only a dummy record with ack if peer has acked our last sent */
540 if (likely(state->acked_gen == gen)) {
541 len = dom_rec_len(dom, 0);
542 *dlen = len;
543 dom->len = htons(len);
544 dom->gen = htons(gen);
545 dom->ack_gen = htons(state->peer_gen);
546 dom->member_cnt = 0;
547 return;
548 }
549 /* Send the full record */
550 read_lock_bh(&mon->lock);
551 len = ntohs(mon->cache.len);
552 *dlen = len;
553 memcpy(data, &mon->cache, len);
554 read_unlock_bh(&mon->lock);
555 dom->ack_gen = htons(state->peer_gen);
556}
557
558void tipc_mon_get_state(struct net *net, u32 addr,
559 struct tipc_mon_state *state,
560 int bearer_id)
561{
562 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
563 struct tipc_peer *peer;
564
565 if (!tipc_mon_is_active(net, mon)) {
566 state->probing = false;
567 state->monitoring = true;
568 return;
569 }
570
571 /* Used cached state if table has not changed */
572 if (!state->probing &&
573 (state->list_gen == mon->list_gen) &&
574 (state->acked_gen == mon->dom_gen))
575 return;
576
577 read_lock_bh(&mon->lock);
578 peer = get_peer(mon, addr);
579 if (peer) {
580 state->probing = state->acked_gen != mon->dom_gen;
581 state->probing |= peer->down_cnt;
582 state->reset |= peer->down_cnt >= MAX_PEER_DOWN_EVENTS;
583 state->monitoring = peer->is_local;
584 state->monitoring |= peer->is_head;
585 state->list_gen = mon->list_gen;
586 }
587 read_unlock_bh(&mon->lock);
588}
589
590static void mon_timeout(struct timer_list *t)
591{
592 struct tipc_monitor *mon = from_timer(mon, t, timer);
593 struct tipc_peer *self;
594 int best_member_cnt = dom_size(mon->peer_cnt) - 1;
595
596 write_lock_bh(&mon->lock);
597 self = mon->self;
598 if (self && (best_member_cnt != self->applied)) {
599 mon_update_local_domain(mon);
600 mon_assign_roles(mon, self);
601 }
602 write_unlock_bh(&mon->lock);
603 mod_timer(&mon->timer, jiffies + mon->timer_intv);
604}
605
606int tipc_mon_create(struct net *net, int bearer_id)
607{
608 struct tipc_net *tn = tipc_net(net);
609 struct tipc_monitor *mon;
610 struct tipc_peer *self;
611 struct tipc_mon_domain *dom;
612
613 if (tn->monitors[bearer_id])
614 return 0;
615
616 mon = kzalloc(sizeof(*mon), GFP_ATOMIC);
617 self = kzalloc(sizeof(*self), GFP_ATOMIC);
618 dom = kzalloc(sizeof(*dom), GFP_ATOMIC);
619 if (!mon || !self || !dom) {
620 kfree(mon);
621 kfree(self);
622 kfree(dom);
623 return -ENOMEM;
624 }
625 tn->monitors[bearer_id] = mon;
626 rwlock_init(&mon->lock);
627 mon->net = net;
628 mon->peer_cnt = 1;
629 mon->self = self;
630 self->domain = dom;
631 self->addr = tipc_own_addr(net);
632 self->is_up = true;
633 self->is_head = true;
634 INIT_LIST_HEAD(&self->list);
635 timer_setup(&mon->timer, mon_timeout, 0);
636 mon->timer_intv = msecs_to_jiffies(MON_TIMEOUT + (tn->random & 0xffff));
637 mod_timer(&mon->timer, jiffies + mon->timer_intv);
638 return 0;
639}
640
641void tipc_mon_delete(struct net *net, int bearer_id)
642{
643 struct tipc_net *tn = tipc_net(net);
644 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
645 struct tipc_peer *self;
646 struct tipc_peer *peer, *tmp;
647
648 if (!mon)
649 return;
650
651 self = get_self(net, bearer_id);
652 write_lock_bh(&mon->lock);
653 tn->monitors[bearer_id] = NULL;
654 list_for_each_entry_safe(peer, tmp, &self->list, list) {
655 list_del(&peer->list);
656 hlist_del(&peer->hash);
657 kfree(peer->domain);
658 kfree(peer);
659 }
660 mon->self = NULL;
661 write_unlock_bh(&mon->lock);
662 del_timer_sync(&mon->timer);
663 kfree(self->domain);
664 kfree(self);
665 kfree(mon);
666}
667
668int tipc_nl_monitor_set_threshold(struct net *net, u32 cluster_size)
669{
670 struct tipc_net *tn = tipc_net(net);
671
672 if (cluster_size > TIPC_CLUSTER_SIZE)
673 return -EINVAL;
674
675 tn->mon_threshold = cluster_size;
676
677 return 0;
678}
679
680int tipc_nl_monitor_get_threshold(struct net *net)
681{
682 struct tipc_net *tn = tipc_net(net);
683
684 return tn->mon_threshold;
685}
686
687int __tipc_nl_add_monitor_peer(struct tipc_peer *peer, struct tipc_nl_msg *msg)
688{
689 struct tipc_mon_domain *dom = peer->domain;
690 struct nlattr *attrs;
691 void *hdr;
692
693 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
694 NLM_F_MULTI, TIPC_NL_MON_PEER_GET);
695 if (!hdr)
696 return -EMSGSIZE;
697
698 attrs = nla_nest_start(msg->skb, TIPC_NLA_MON_PEER);
699 if (!attrs)
700 goto msg_full;
701
702 if (nla_put_u32(msg->skb, TIPC_NLA_MON_PEER_ADDR, peer->addr))
703 goto attr_msg_full;
704 if (nla_put_u32(msg->skb, TIPC_NLA_MON_PEER_APPLIED, peer->applied))
705 goto attr_msg_full;
706
707 if (peer->is_up)
708 if (nla_put_flag(msg->skb, TIPC_NLA_MON_PEER_UP))
709 goto attr_msg_full;
710 if (peer->is_local)
711 if (nla_put_flag(msg->skb, TIPC_NLA_MON_PEER_LOCAL))
712 goto attr_msg_full;
713 if (peer->is_head)
714 if (nla_put_flag(msg->skb, TIPC_NLA_MON_PEER_HEAD))
715 goto attr_msg_full;
716
717 if (dom) {
718 if (nla_put_u32(msg->skb, TIPC_NLA_MON_PEER_DOMGEN, dom->gen))
719 goto attr_msg_full;
720 if (nla_put_u64_64bit(msg->skb, TIPC_NLA_MON_PEER_UPMAP,
721 dom->up_map, TIPC_NLA_MON_PEER_PAD))
722 goto attr_msg_full;
723 if (nla_put(msg->skb, TIPC_NLA_MON_PEER_MEMBERS,
724 dom->member_cnt * sizeof(u32), &dom->members))
725 goto attr_msg_full;
726 }
727
728 nla_nest_end(msg->skb, attrs);
729 genlmsg_end(msg->skb, hdr);
730 return 0;
731
732attr_msg_full:
733 nla_nest_cancel(msg->skb, attrs);
734msg_full:
735 genlmsg_cancel(msg->skb, hdr);
736
737 return -EMSGSIZE;
738}
739
740int tipc_nl_add_monitor_peer(struct net *net, struct tipc_nl_msg *msg,
741 u32 bearer_id, u32 *prev_node)
742{
743 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
744 struct tipc_peer *peer;
745
746 if (!mon)
747 return -EINVAL;
748
749 read_lock_bh(&mon->lock);
750 peer = mon->self;
751 do {
752 if (*prev_node) {
753 if (peer->addr == *prev_node)
754 *prev_node = 0;
755 else
756 continue;
757 }
758 if (__tipc_nl_add_monitor_peer(peer, msg)) {
759 *prev_node = peer->addr;
760 read_unlock_bh(&mon->lock);
761 return -EMSGSIZE;
762 }
763 } while ((peer = peer_nxt(peer)) != mon->self);
764 read_unlock_bh(&mon->lock);
765
766 return 0;
767}
768
769int __tipc_nl_add_monitor(struct net *net, struct tipc_nl_msg *msg,
770 u32 bearer_id)
771{
772 struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
773 char bearer_name[TIPC_MAX_BEARER_NAME];
774 struct nlattr *attrs;
775 void *hdr;
776 int ret;
777
778 ret = tipc_bearer_get_name(net, bearer_name, bearer_id);
779 if (ret || !mon)
780 return 0;
781
782 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
783 NLM_F_MULTI, TIPC_NL_MON_GET);
784 if (!hdr)
785 return -EMSGSIZE;
786
787 attrs = nla_nest_start(msg->skb, TIPC_NLA_MON);
788 if (!attrs)
789 goto msg_full;
790
791 read_lock_bh(&mon->lock);
792 if (nla_put_u32(msg->skb, TIPC_NLA_MON_REF, bearer_id))
793 goto attr_msg_full;
794 if (tipc_mon_is_active(net, mon))
795 if (nla_put_flag(msg->skb, TIPC_NLA_MON_ACTIVE))
796 goto attr_msg_full;
797 if (nla_put_string(msg->skb, TIPC_NLA_MON_BEARER_NAME, bearer_name))
798 goto attr_msg_full;
799 if (nla_put_u32(msg->skb, TIPC_NLA_MON_PEERCNT, mon->peer_cnt))
800 goto attr_msg_full;
801 if (nla_put_u32(msg->skb, TIPC_NLA_MON_LISTGEN, mon->list_gen))
802 goto attr_msg_full;
803
804 read_unlock_bh(&mon->lock);
805 nla_nest_end(msg->skb, attrs);
806 genlmsg_end(msg->skb, hdr);
807
808 return 0;
809
810attr_msg_full:
811 read_unlock_bh(&mon->lock);
812 nla_nest_cancel(msg->skb, attrs);
813msg_full:
814 genlmsg_cancel(msg->skb, hdr);
815
816 return -EMSGSIZE;
817}