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Merge branch 'x86/rdrand' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
[wandboard.git] / net / 802 / garp.c
blob8e21b6db3981cc93cb5e4e00e30b820c9ff97af1
1 /*
2 * IEEE 802.1D Generic Attribute Registration Protocol (GARP)
3 *
4 * Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * version 2 as published by the Free Software Foundation.
9 */
10 #include <linux/kernel.h>
11 #include <linux/timer.h>
12 #include <linux/skbuff.h>
13 #include <linux/netdevice.h>
14 #include <linux/etherdevice.h>
15 #include <linux/rtnetlink.h>
16 #include <linux/llc.h>
17 #include <linux/slab.h>
18 #include <linux/module.h>
19 #include <net/llc.h>
20 #include <net/llc_pdu.h>
21 #include <net/garp.h>
22 #include <asm/unaligned.h>
23
24 static unsigned int garp_join_time __read_mostly = 200;
25 module_param(garp_join_time, uint, 0644);
26 MODULE_PARM_DESC(garp_join_time, "Join time in ms (default 200ms)");
27 MODULE_LICENSE("GPL");
28
29 static const struct garp_state_trans {
30 u8 state;
31 u8 action;
32 } garp_applicant_state_table[GARP_APPLICANT_MAX + 1][GARP_EVENT_MAX + 1] = {
33 [GARP_APPLICANT_VA] = {
34 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA,
35 .action = GARP_ACTION_S_JOIN_IN },
36 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AA },
37 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
38 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
39 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA },
40 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
41 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
42 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
43 },
44 [GARP_APPLICANT_AA] = {
45 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA,
46 .action = GARP_ACTION_S_JOIN_IN },
47 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA },
48 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
49 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
50 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA },
51 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
52 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
53 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
54 },
55 [GARP_APPLICANT_QA] = {
56 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
57 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA },
58 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
59 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
60 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
61 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
62 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
63 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
64 },
65 [GARP_APPLICANT_LA] = {
66 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_VO,
67 .action = GARP_ACTION_S_LEAVE_EMPTY },
68 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_LA },
69 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
70 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_LA },
71 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_LA },
72 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
73 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VA },
74 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
75 },
76 [GARP_APPLICANT_VP] = {
77 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA,
78 .action = GARP_ACTION_S_JOIN_IN },
79 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AP },
80 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
81 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
82 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
83 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
84 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
85 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_VO },
86 },
87 [GARP_APPLICANT_AP] = {
88 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA,
89 .action = GARP_ACTION_S_JOIN_IN },
90 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP },
91 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
92 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
93 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
94 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
95 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
96 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_AO },
97 },
98 [GARP_APPLICANT_QP] = {
99 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
100 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP },
101 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
102 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
103 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
104 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
105 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
106 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_QO },
107 },
108 [GARP_APPLICANT_VO] = {
109 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
110 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AO },
111 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
112 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
113 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
114 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
115 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VP },
116 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
117 },
118 [GARP_APPLICANT_AO] = {
119 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
120 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO },
121 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
122 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
123 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
124 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
125 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_AP },
126 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
127 },
128 [GARP_APPLICANT_QO] = {
129 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
130 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO },
131 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
132 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
133 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
134 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
135 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_QP },
136 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
137 },
138 };
139
140 static int garp_attr_cmp(const struct garp_attr *attr,
141 const void *data, u8 len, u8 type)
142 {
143 if (attr->type != type)
144 return attr->type - type;
145 if (attr->dlen != len)
146 return attr->dlen - len;
147 return memcmp(attr->data, data, len);
148 }
149
150 static struct garp_attr *garp_attr_lookup(const struct garp_applicant *app,
151 const void *data, u8 len, u8 type)
152 {
153 struct rb_node *parent = app->gid.rb_node;
154 struct garp_attr *attr;
155 int d;
156
157 while (parent) {
158 attr = rb_entry(parent, struct garp_attr, node);
159 d = garp_attr_cmp(attr, data, len, type);
160 if (d < 0)
161 parent = parent->rb_left;
162 else if (d > 0)
163 parent = parent->rb_right;
164 else
165 return attr;
166 }
167 return NULL;
168 }
169
170 static void garp_attr_insert(struct garp_applicant *app, struct garp_attr *new)
171 {
172 struct rb_node *parent = NULL, **p = &app->gid.rb_node;
173 struct garp_attr *attr;
174 int d;
175
176 while (*p) {
177 parent = *p;
178 attr = rb_entry(parent, struct garp_attr, node);
179 d = garp_attr_cmp(attr, new->data, new->dlen, new->type);
180 if (d < 0)
181 p = &parent->rb_left;
182 else if (d > 0)
183 p = &parent->rb_right;
184 }
185 rb_link_node(&new->node, parent, p);
186 rb_insert_color(&new->node, &app->gid);
187 }
188
189 static struct garp_attr *garp_attr_create(struct garp_applicant *app,
190 const void *data, u8 len, u8 type)
191 {
192 struct garp_attr *attr;
193
194 attr = kmalloc(sizeof(*attr) + len, GFP_ATOMIC);
195 if (!attr)
196 return attr;
197 attr->state = GARP_APPLICANT_VO;
198 attr->type = type;
199 attr->dlen = len;
200 memcpy(attr->data, data, len);
201 garp_attr_insert(app, attr);
202 return attr;
203 }
204
205 static void garp_attr_destroy(struct garp_applicant *app, struct garp_attr *attr)
206 {
207 rb_erase(&attr->node, &app->gid);
208 kfree(attr);
209 }
210
211 static int garp_pdu_init(struct garp_applicant *app)
212 {
213 struct sk_buff *skb;
214 struct garp_pdu_hdr *gp;
215
216 #define LLC_RESERVE sizeof(struct llc_pdu_un)
217 skb = alloc_skb(app->dev->mtu + LL_RESERVED_SPACE(app->dev),
218 GFP_ATOMIC);
219 if (!skb)
220 return -ENOMEM;
221
222 skb->dev = app->dev;
223 skb->protocol = htons(ETH_P_802_2);
224 skb_reserve(skb, LL_RESERVED_SPACE(app->dev) + LLC_RESERVE);
225
226 gp = (struct garp_pdu_hdr *)__skb_put(skb, sizeof(*gp));
227 put_unaligned(htons(GARP_PROTOCOL_ID), &gp->protocol);
228
229 app->pdu = skb;
230 return 0;
231 }
232
233 static int garp_pdu_append_end_mark(struct garp_applicant *app)
234 {
235 if (skb_tailroom(app->pdu) < sizeof(u8))
236 return -1;
237 *(u8 *)__skb_put(app->pdu, sizeof(u8)) = GARP_END_MARK;
238 return 0;
239 }
240
241 static void garp_pdu_queue(struct garp_applicant *app)
242 {
243 if (!app->pdu)
244 return;
245
246 garp_pdu_append_end_mark(app);
247 garp_pdu_append_end_mark(app);
248
249 llc_pdu_header_init(app->pdu, LLC_PDU_TYPE_U, LLC_SAP_BSPAN,
250 LLC_SAP_BSPAN, LLC_PDU_CMD);
251 llc_pdu_init_as_ui_cmd(app->pdu);
252 llc_mac_hdr_init(app->pdu, app->dev->dev_addr,
253 app->app->proto.group_address);
254
255 skb_queue_tail(&app->queue, app->pdu);
256 app->pdu = NULL;
257 }
258
259 static void garp_queue_xmit(struct garp_applicant *app)
260 {
261 struct sk_buff *skb;
262
263 while ((skb = skb_dequeue(&app->queue)))
264 dev_queue_xmit(skb);
265 }
266
267 static int garp_pdu_append_msg(struct garp_applicant *app, u8 attrtype)
268 {
269 struct garp_msg_hdr *gm;
270
271 if (skb_tailroom(app->pdu) < sizeof(*gm))
272 return -1;
273 gm = (struct garp_msg_hdr *)__skb_put(app->pdu, sizeof(*gm));
274 gm->attrtype = attrtype;
275 garp_cb(app->pdu)->cur_type = attrtype;
276 return 0;
277 }
278
279 static int garp_pdu_append_attr(struct garp_applicant *app,
280 const struct garp_attr *attr,
281 enum garp_attr_event event)
282 {
283 struct garp_attr_hdr *ga;
284 unsigned int len;
285 int err;
286 again:
287 if (!app->pdu) {
288 err = garp_pdu_init(app);
289 if (err < 0)
290 return err;
291 }
292
293 if (garp_cb(app->pdu)->cur_type != attr->type) {
294 if (garp_cb(app->pdu)->cur_type &&
295 garp_pdu_append_end_mark(app) < 0)
296 goto queue;
297 if (garp_pdu_append_msg(app, attr->type) < 0)
298 goto queue;
299 }
300
301 len = sizeof(*ga) + attr->dlen;
302 if (skb_tailroom(app->pdu) < len)
303 goto queue;
304 ga = (struct garp_attr_hdr *)__skb_put(app->pdu, len);
305 ga->len = len;
306 ga->event = event;
307 memcpy(ga->data, attr->data, attr->dlen);
308 return 0;
309
310 queue:
311 garp_pdu_queue(app);
312 goto again;
313 }
314
315 static void garp_attr_event(struct garp_applicant *app,
316 struct garp_attr *attr, enum garp_event event)
317 {
318 enum garp_applicant_state state;
319
320 state = garp_applicant_state_table[attr->state][event].state;
321 if (state == GARP_APPLICANT_INVALID)
322 return;
323
324 switch (garp_applicant_state_table[attr->state][event].action) {
325 case GARP_ACTION_NONE:
326 break;
327 case GARP_ACTION_S_JOIN_IN:
328 /* When appending the attribute fails, don't update state in
329 * order to retry on next TRANSMIT_PDU event. */
330 if (garp_pdu_append_attr(app, attr, GARP_JOIN_IN) < 0)
331 return;
332 break;
333 case GARP_ACTION_S_LEAVE_EMPTY:
334 garp_pdu_append_attr(app, attr, GARP_LEAVE_EMPTY);
335 /* As a pure applicant, sending a leave message implies that
336 * the attribute was unregistered and can be destroyed. */
337 garp_attr_destroy(app, attr);
338 return;
339 default:
340 WARN_ON(1);
341 }
342
343 attr->state = state;
344 }
345
346 int garp_request_join(const struct net_device *dev,
347 const struct garp_application *appl,
348 const void *data, u8 len, u8 type)
349 {
350 struct garp_port *port = rtnl_dereference(dev->garp_port);
351 struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]);
352 struct garp_attr *attr;
353
354 spin_lock_bh(&app->lock);
355 attr = garp_attr_create(app, data, len, type);
356 if (!attr) {
357 spin_unlock_bh(&app->lock);
358 return -ENOMEM;
359 }
360 garp_attr_event(app, attr, GARP_EVENT_REQ_JOIN);
361 spin_unlock_bh(&app->lock);
362 return 0;
363 }
364 EXPORT_SYMBOL_GPL(garp_request_join);
365
366 void garp_request_leave(const struct net_device *dev,
367 const struct garp_application *appl,
368 const void *data, u8 len, u8 type)
369 {
370 struct garp_port *port = rtnl_dereference(dev->garp_port);
371 struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]);
372 struct garp_attr *attr;
373
374 spin_lock_bh(&app->lock);
375 attr = garp_attr_lookup(app, data, len, type);
376 if (!attr) {
377 spin_unlock_bh(&app->lock);
378 return;
379 }
380 garp_attr_event(app, attr, GARP_EVENT_REQ_LEAVE);
381 spin_unlock_bh(&app->lock);
382 }
383 EXPORT_SYMBOL_GPL(garp_request_leave);
384
385 static void garp_gid_event(struct garp_applicant *app, enum garp_event event)
386 {
387 struct rb_node *node, *next;
388 struct garp_attr *attr;
389
390 for (node = rb_first(&app->gid);
391 next = node ? rb_next(node) : NULL, node != NULL;
392 node = next) {
393 attr = rb_entry(node, struct garp_attr, node);
394 garp_attr_event(app, attr, event);
395 }
396 }
397
398 static void garp_join_timer_arm(struct garp_applicant *app)
399 {
400 unsigned long delay;
401
402 delay = (u64)msecs_to_jiffies(garp_join_time) * net_random() >> 32;
403 mod_timer(&app->join_timer, jiffies + delay);
404 }
405
406 static void garp_join_timer(unsigned long data)
407 {
408 struct garp_applicant *app = (struct garp_applicant *)data;
409
410 spin_lock(&app->lock);
411 garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU);
412 garp_pdu_queue(app);
413 spin_unlock(&app->lock);
414
415 garp_queue_xmit(app);
416 garp_join_timer_arm(app);
417 }
418
419 static int garp_pdu_parse_end_mark(struct sk_buff *skb)
420 {
421 if (!pskb_may_pull(skb, sizeof(u8)))
422 return -1;
423 if (*skb->data == GARP_END_MARK) {
424 skb_pull(skb, sizeof(u8));
425 return -1;
426 }
427 return 0;
428 }
429
430 static int garp_pdu_parse_attr(struct garp_applicant *app, struct sk_buff *skb,
431 u8 attrtype)
432 {
433 const struct garp_attr_hdr *ga;
434 struct garp_attr *attr;
435 enum garp_event event;
436 unsigned int dlen;
437
438 if (!pskb_may_pull(skb, sizeof(*ga)))
439 return -1;
440 ga = (struct garp_attr_hdr *)skb->data;
441 if (ga->len < sizeof(*ga))
442 return -1;
443
444 if (!pskb_may_pull(skb, ga->len))
445 return -1;
446 skb_pull(skb, ga->len);
447 dlen = sizeof(*ga) - ga->len;
448
449 if (attrtype > app->app->maxattr)
450 return 0;
451
452 switch (ga->event) {
453 case GARP_LEAVE_ALL:
454 if (dlen != 0)
455 return -1;
456 garp_gid_event(app, GARP_EVENT_R_LEAVE_EMPTY);
457 return 0;
458 case GARP_JOIN_EMPTY:
459 event = GARP_EVENT_R_JOIN_EMPTY;
460 break;
461 case GARP_JOIN_IN:
462 event = GARP_EVENT_R_JOIN_IN;
463 break;
464 case GARP_LEAVE_EMPTY:
465 event = GARP_EVENT_R_LEAVE_EMPTY;
466 break;
467 case GARP_EMPTY:
468 event = GARP_EVENT_R_EMPTY;
469 break;
470 default:
471 return 0;
472 }
473
474 if (dlen == 0)
475 return -1;
476 attr = garp_attr_lookup(app, ga->data, dlen, attrtype);
477 if (attr == NULL)
478 return 0;
479 garp_attr_event(app, attr, event);
480 return 0;
481 }
482
483 static int garp_pdu_parse_msg(struct garp_applicant *app, struct sk_buff *skb)
484 {
485 const struct garp_msg_hdr *gm;
486
487 if (!pskb_may_pull(skb, sizeof(*gm)))
488 return -1;
489 gm = (struct garp_msg_hdr *)skb->data;
490 if (gm->attrtype == 0)
491 return -1;
492 skb_pull(skb, sizeof(*gm));
493
494 while (skb->len > 0) {
495 if (garp_pdu_parse_attr(app, skb, gm->attrtype) < 0)
496 return -1;
497 if (garp_pdu_parse_end_mark(skb) < 0)
498 break;
499 }
500 return 0;
501 }
502
503 static void garp_pdu_rcv(const struct stp_proto *proto, struct sk_buff *skb,
504 struct net_device *dev)
505 {
506 struct garp_application *appl = proto->data;
507 struct garp_port *port;
508 struct garp_applicant *app;
509 const struct garp_pdu_hdr *gp;
510
511 port = rcu_dereference(dev->garp_port);
512 if (!port)
513 goto err;
514 app = rcu_dereference(port->applicants[appl->type]);
515 if (!app)
516 goto err;
517
518 if (!pskb_may_pull(skb, sizeof(*gp)))
519 goto err;
520 gp = (struct garp_pdu_hdr *)skb->data;
521 if (get_unaligned(&gp->protocol) != htons(GARP_PROTOCOL_ID))
522 goto err;
523 skb_pull(skb, sizeof(*gp));
524
525 spin_lock(&app->lock);
526 while (skb->len > 0) {
527 if (garp_pdu_parse_msg(app, skb) < 0)
528 break;
529 if (garp_pdu_parse_end_mark(skb) < 0)
530 break;
531 }
532 spin_unlock(&app->lock);
533 err:
534 kfree_skb(skb);
535 }
536
537 static int garp_init_port(struct net_device *dev)
538 {
539 struct garp_port *port;
540
541 port = kzalloc(sizeof(*port), GFP_KERNEL);
542 if (!port)
543 return -ENOMEM;
544 rcu_assign_pointer(dev->garp_port, port);
545 return 0;
546 }
547
548 static void garp_release_port(struct net_device *dev)
549 {
550 struct garp_port *port = rtnl_dereference(dev->garp_port);
551 unsigned int i;
552
553 for (i = 0; i <= GARP_APPLICATION_MAX; i++) {
554 if (rtnl_dereference(port->applicants[i]))
555 return;
556 }
557 RCU_INIT_POINTER(dev->garp_port, NULL);
558 kfree_rcu(port, rcu);
559 }
560
561 int garp_init_applicant(struct net_device *dev, struct garp_application *appl)
562 {
563 struct garp_applicant *app;
564 int err;
565
566 ASSERT_RTNL();
567
568 if (!rtnl_dereference(dev->garp_port)) {
569 err = garp_init_port(dev);
570 if (err < 0)
571 goto err1;
572 }
573
574 err = -ENOMEM;
575 app = kzalloc(sizeof(*app), GFP_KERNEL);
576 if (!app)
577 goto err2;
578
579 err = dev_mc_add(dev, appl->proto.group_address);
580 if (err < 0)
581 goto err3;
582
583 app->dev = dev;
584 app->app = appl;
585 app->gid = RB_ROOT;
586 spin_lock_init(&app->lock);
587 skb_queue_head_init(&app->queue);
588 rcu_assign_pointer(dev->garp_port->applicants[appl->type], app);
589 setup_timer(&app->join_timer, garp_join_timer, (unsigned long)app);
590 garp_join_timer_arm(app);
591 return 0;
592
593 err3:
594 kfree(app);
595 err2:
596 garp_release_port(dev);
597 err1:
598 return err;
599 }
600 EXPORT_SYMBOL_GPL(garp_init_applicant);
601
602 void garp_uninit_applicant(struct net_device *dev, struct garp_application *appl)
603 {
604 struct garp_port *port = rtnl_dereference(dev->garp_port);
605 struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]);
606
607 ASSERT_RTNL();
608
609 RCU_INIT_POINTER(port->applicants[appl->type], NULL);
610
611 /* Delete timer and generate a final TRANSMIT_PDU event to flush out
612 * all pending messages before the applicant is gone. */
613 del_timer_sync(&app->join_timer);
614 garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU);
615 garp_pdu_queue(app);
616 garp_queue_xmit(app);
617
618 dev_mc_del(dev, appl->proto.group_address);
619 kfree_rcu(app, rcu);
620 garp_release_port(dev);
621 }
622 EXPORT_SYMBOL_GPL(garp_uninit_applicant);
623
624 int garp_register_application(struct garp_application *appl)
625 {
626 appl->proto.rcv = garp_pdu_rcv;
627 appl->proto.data = appl;
628 return stp_proto_register(&appl->proto);
629 }
630 EXPORT_SYMBOL_GPL(garp_register_application);
631
632 void garp_unregister_application(struct garp_application *appl)
633 {
634 stp_proto_unregister(&appl->proto);
635 }
636 EXPORT_SYMBOL_GPL(garp_unregister_application);
WandBoard kernel