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Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6.git] / net / mac80211 / mesh_hwmp.c
blob486819cd02cd7d03924e30d4e93f7ac201248b4c
1 /*
2 * Copyright (c) 2008, 2009 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9
10 #include <linux/slab.h>
11 #include <linux/etherdevice.h>
12 #include <asm/unaligned.h>
13 #include "wme.h"
14 #include "mesh.h"
15
16 #define TEST_FRAME_LEN 8192
17 #define MAX_METRIC 0xffffffff
18 #define ARITH_SHIFT 8
19
20 #define MAX_PREQ_QUEUE_LEN 64
21
22 /* Destination only */
23 #define MP_F_DO 0x1
24 /* Reply and forward */
25 #define MP_F_RF 0x2
26 /* Unknown Sequence Number */
27 #define MP_F_USN 0x01
28 /* Reason code Present */
29 #define MP_F_RCODE 0x02
30
31 static void mesh_queue_preq(struct mesh_path *, u8);
32
33 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae)
34 {
35 if (ae)
36 offset += 6;
37 return get_unaligned_le32(preq_elem + offset);
38 }
39
40 static inline u32 u16_field_get(const u8 *preq_elem, int offset, bool ae)
41 {
42 if (ae)
43 offset += 6;
44 return get_unaligned_le16(preq_elem + offset);
45 }
46
47 /* HWMP IE processing macros */
48 #define AE_F (1<<6)
49 #define AE_F_SET(x) (*x & AE_F)
50 #define PREQ_IE_FLAGS(x) (*(x))
51 #define PREQ_IE_HOPCOUNT(x) (*(x + 1))
52 #define PREQ_IE_TTL(x) (*(x + 2))
53 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
54 #define PREQ_IE_ORIG_ADDR(x) (x + 7)
55 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0)
56 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x))
57 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x))
58 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
59 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
60 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x))
61
62
63 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
64 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
65 #define PREP_IE_TTL(x) PREQ_IE_TTL(x)
66 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
67 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x))
68 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x))
69 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x))
70 #define PREP_IE_TARGET_ADDR(x) (x + 3)
71 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
72
73 #define PERR_IE_TTL(x) (*(x))
74 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2))
75 #define PERR_IE_TARGET_ADDR(x) (x + 3)
76 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
77 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0)
78
79 #define MSEC_TO_TU(x) (x*1000/1024)
80 #define SN_GT(x, y) ((s32)(y - x) < 0)
81 #define SN_LT(x, y) ((s32)(x - y) < 0)
82
83 #define net_traversal_jiffies(s) \
84 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
85 #define default_lifetime(s) \
86 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout)
87 #define min_preq_int_jiff(s) \
88 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval))
89 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries)
90 #define disc_timeout_jiff(s) \
91 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout)
92 #define root_path_confirmation_jiffies(s) \
93 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval)
94
95 enum mpath_frame_type {
96 MPATH_PREQ = 0,
97 MPATH_PREP,
98 MPATH_PERR,
99 MPATH_RANN
100 };
101
102 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
103
104 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
105 const u8 *orig_addr, __le32 orig_sn,
106 u8 target_flags, const u8 *target,
107 __le32 target_sn, const u8 *da,
108 u8 hop_count, u8 ttl,
109 __le32 lifetime, __le32 metric,
110 __le32 preq_id,
111 struct ieee80211_sub_if_data *sdata)
112 {
113 struct ieee80211_local *local = sdata->local;
114 struct sk_buff *skb;
115 struct ieee80211_mgmt *mgmt;
116 u8 *pos, ie_len;
117 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
118 sizeof(mgmt->u.action.u.mesh_action);
119
120 skb = dev_alloc_skb(local->tx_headroom +
121 hdr_len +
122 2 + 37); /* max HWMP IE */
123 if (!skb)
124 return -1;
125 skb_reserve(skb, local->tx_headroom);
126 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
127 memset(mgmt, 0, hdr_len);
128 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
129 IEEE80211_STYPE_ACTION);
130
131 memcpy(mgmt->da, da, ETH_ALEN);
132 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
133 /* BSSID == SA */
134 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
135 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
136 mgmt->u.action.u.mesh_action.action_code =
137 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
138
139 switch (action) {
140 case MPATH_PREQ:
141 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target);
142 ie_len = 37;
143 pos = skb_put(skb, 2 + ie_len);
144 *pos++ = WLAN_EID_PREQ;
145 break;
146 case MPATH_PREP:
147 mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr);
148 ie_len = 31;
149 pos = skb_put(skb, 2 + ie_len);
150 *pos++ = WLAN_EID_PREP;
151 break;
152 case MPATH_RANN:
153 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr);
154 ie_len = sizeof(struct ieee80211_rann_ie);
155 pos = skb_put(skb, 2 + ie_len);
156 *pos++ = WLAN_EID_RANN;
157 break;
158 default:
159 kfree_skb(skb);
160 return -ENOTSUPP;
161 break;
162 }
163 *pos++ = ie_len;
164 *pos++ = flags;
165 *pos++ = hop_count;
166 *pos++ = ttl;
167 if (action == MPATH_PREP) {
168 memcpy(pos, target, ETH_ALEN);
169 pos += ETH_ALEN;
170 memcpy(pos, &target_sn, 4);
171 pos += 4;
172 } else {
173 if (action == MPATH_PREQ) {
174 memcpy(pos, &preq_id, 4);
175 pos += 4;
176 }
177 memcpy(pos, orig_addr, ETH_ALEN);
178 pos += ETH_ALEN;
179 memcpy(pos, &orig_sn, 4);
180 pos += 4;
181 }
182 memcpy(pos, &lifetime, 4); /* interval for RANN */
183 pos += 4;
184 memcpy(pos, &metric, 4);
185 pos += 4;
186 if (action == MPATH_PREQ) {
187 *pos++ = 1; /* destination count */
188 *pos++ = target_flags;
189 memcpy(pos, target, ETH_ALEN);
190 pos += ETH_ALEN;
191 memcpy(pos, &target_sn, 4);
192 pos += 4;
193 } else if (action == MPATH_PREP) {
194 memcpy(pos, orig_addr, ETH_ALEN);
195 pos += ETH_ALEN;
196 memcpy(pos, &orig_sn, 4);
197 pos += 4;
198 }
199
200 ieee80211_tx_skb(sdata, skb);
201 return 0;
202 }
203
204
205 /* Headroom is not adjusted. Caller should ensure that skb has sufficient
206 * headroom in case the frame is encrypted. */
207 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
208 struct sk_buff *skb)
209 {
210 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
211 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
212
213 skb_set_mac_header(skb, 0);
214 skb_set_network_header(skb, 0);
215 skb_set_transport_header(skb, 0);
216
217 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
218 skb_set_queue_mapping(skb, IEEE80211_AC_VO);
219 skb->priority = 7;
220
221 info->control.vif = &sdata->vif;
222 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
223 ieee80211_set_qos_hdr(sdata, skb);
224 ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
225 }
226
227 /**
228 * mesh_path_error_tx - Sends a PERR mesh management frame
229 *
230 * @ttl: allowed remaining hops
231 * @target: broken destination
232 * @target_sn: SN of the broken destination
233 * @target_rcode: reason code for this PERR
234 * @ra: node this frame is addressed to
235 * @sdata: local mesh subif
236 *
237 * Note: This function may be called with driver locks taken that the driver
238 * also acquires in the TX path. To avoid a deadlock we don't transmit the
239 * frame directly but add it to the pending queue instead.
240 */
241 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
242 u8 ttl, const u8 *target, __le32 target_sn,
243 __le16 target_rcode, const u8 *ra)
244 {
245 struct ieee80211_local *local = sdata->local;
246 struct sk_buff *skb;
247 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
248 struct ieee80211_mgmt *mgmt;
249 u8 *pos, ie_len;
250 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
251 sizeof(mgmt->u.action.u.mesh_action);
252
253 if (time_before(jiffies, ifmsh->next_perr))
254 return -EAGAIN;
255
256 skb = dev_alloc_skb(local->tx_headroom +
257 IEEE80211_ENCRYPT_HEADROOM +
258 IEEE80211_ENCRYPT_TAILROOM +
259 hdr_len +
260 2 + 15 /* PERR IE */);
261 if (!skb)
262 return -1;
263 skb_reserve(skb, local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM);
264 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
265 memset(mgmt, 0, hdr_len);
266 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
267 IEEE80211_STYPE_ACTION);
268
269 memcpy(mgmt->da, ra, ETH_ALEN);
270 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
271 /* BSSID == SA */
272 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
273 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
274 mgmt->u.action.u.mesh_action.action_code =
275 WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
276 ie_len = 15;
277 pos = skb_put(skb, 2 + ie_len);
278 *pos++ = WLAN_EID_PERR;
279 *pos++ = ie_len;
280 /* ttl */
281 *pos++ = ttl;
282 /* number of destinations */
283 *pos++ = 1;
284 /*
285 * flags bit, bit 1 is unset if we know the sequence number and
286 * bit 2 is set if we have a reason code
287 */
288 *pos = 0;
289 if (!target_sn)
290 *pos |= MP_F_USN;
291 if (target_rcode)
292 *pos |= MP_F_RCODE;
293 pos++;
294 memcpy(pos, target, ETH_ALEN);
295 pos += ETH_ALEN;
296 memcpy(pos, &target_sn, 4);
297 pos += 4;
298 memcpy(pos, &target_rcode, 2);
299
300 /* see note in function header */
301 prepare_frame_for_deferred_tx(sdata, skb);
302 ifmsh->next_perr = TU_TO_EXP_TIME(
303 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval);
304 ieee80211_add_pending_skb(local, skb);
305 return 0;
306 }
307
308 void ieee80211s_update_metric(struct ieee80211_local *local,
309 struct sta_info *sta, struct sk_buff *skb)
310 {
311 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
312 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
313 int failed;
314
315 if (!ieee80211_is_data(hdr->frame_control))
316 return;
317
318 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
319
320 /* moving average, scaled to 100 */
321 sta->fail_avg = ((80 * sta->fail_avg + 5) / 100 + 20 * failed);
322 if (sta->fail_avg > 95)
323 mesh_plink_broken(sta);
324 }
325
326 static u32 airtime_link_metric_get(struct ieee80211_local *local,
327 struct sta_info *sta)
328 {
329 struct rate_info rinfo;
330 /* This should be adjusted for each device */
331 int device_constant = 1 << ARITH_SHIFT;
332 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
333 int s_unit = 1 << ARITH_SHIFT;
334 int rate, err;
335 u32 tx_time, estimated_retx;
336 u64 result;
337
338 if (sta->fail_avg >= 100)
339 return MAX_METRIC;
340
341 sta_set_rate_info_tx(sta, &sta->last_tx_rate, &rinfo);
342 rate = cfg80211_calculate_bitrate(&rinfo);
343 if (WARN_ON(!rate))
344 return MAX_METRIC;
345
346 err = (sta->fail_avg << ARITH_SHIFT) / 100;
347
348 /* bitrate is in units of 100 Kbps, while we need rate in units of
349 * 1Mbps. This will be corrected on tx_time computation.
350 */
351 tx_time = (device_constant + 10 * test_frame_len / rate);
352 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
353 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ;
354 return (u32)result;
355 }
356
357 /**
358 * hwmp_route_info_get - Update routing info to originator and transmitter
359 *
360 * @sdata: local mesh subif
361 * @mgmt: mesh management frame
362 * @hwmp_ie: hwmp information element (PREP or PREQ)
363 * @action: type of hwmp ie
364 *
365 * This function updates the path routing information to the originator and the
366 * transmitter of a HWMP PREQ or PREP frame.
367 *
368 * Returns: metric to frame originator or 0 if the frame should not be further
369 * processed
370 *
371 * Notes: this function is the only place (besides user-provided info) where
372 * path routing information is updated.
373 */
374 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
375 struct ieee80211_mgmt *mgmt,
376 const u8 *hwmp_ie, enum mpath_frame_type action)
377 {
378 struct ieee80211_local *local = sdata->local;
379 struct mesh_path *mpath;
380 struct sta_info *sta;
381 bool fresh_info;
382 const u8 *orig_addr, *ta;
383 u32 orig_sn, orig_metric;
384 unsigned long orig_lifetime, exp_time;
385 u32 last_hop_metric, new_metric;
386 bool process = true;
387
388 rcu_read_lock();
389 sta = sta_info_get(sdata, mgmt->sa);
390 if (!sta) {
391 rcu_read_unlock();
392 return 0;
393 }
394
395 last_hop_metric = airtime_link_metric_get(local, sta);
396 /* Update and check originator routing info */
397 fresh_info = true;
398
399 switch (action) {
400 case MPATH_PREQ:
401 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
402 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
403 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
404 orig_metric = PREQ_IE_METRIC(hwmp_ie);
405 break;
406 case MPATH_PREP:
407 /* Originator here refers to the MP that was the target in the
408 * Path Request. We divert from the nomenclature in the draft
409 * so that we can easily use a single function to gather path
410 * information from both PREQ and PREP frames.
411 */
412 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
413 orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
414 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
415 orig_metric = PREP_IE_METRIC(hwmp_ie);
416 break;
417 default:
418 rcu_read_unlock();
419 return 0;
420 }
421 new_metric = orig_metric + last_hop_metric;
422 if (new_metric < orig_metric)
423 new_metric = MAX_METRIC;
424 exp_time = TU_TO_EXP_TIME(orig_lifetime);
425
426 if (ether_addr_equal(orig_addr, sdata->vif.addr)) {
427 /* This MP is the originator, we are not interested in this
428 * frame, except for updating transmitter's path info.
429 */
430 process = false;
431 fresh_info = false;
432 } else {
433 mpath = mesh_path_lookup(sdata, orig_addr);
434 if (mpath) {
435 spin_lock_bh(&mpath->state_lock);
436 if (mpath->flags & MESH_PATH_FIXED)
437 fresh_info = false;
438 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
439 (mpath->flags & MESH_PATH_SN_VALID)) {
440 if (SN_GT(mpath->sn, orig_sn) ||
441 (mpath->sn == orig_sn &&
442 new_metric >= mpath->metric)) {
443 process = false;
444 fresh_info = false;
445 }
446 }
447 } else {
448 mpath = mesh_path_add(sdata, orig_addr);
449 if (IS_ERR(mpath)) {
450 rcu_read_unlock();
451 return 0;
452 }
453 spin_lock_bh(&mpath->state_lock);
454 }
455
456 if (fresh_info) {
457 mesh_path_assign_nexthop(mpath, sta);
458 mpath->flags |= MESH_PATH_SN_VALID;
459 mpath->metric = new_metric;
460 mpath->sn = orig_sn;
461 mpath->exp_time = time_after(mpath->exp_time, exp_time)
462 ? mpath->exp_time : exp_time;
463 mesh_path_activate(mpath);
464 spin_unlock_bh(&mpath->state_lock);
465 mesh_path_tx_pending(mpath);
466 /* draft says preq_id should be saved to, but there does
467 * not seem to be any use for it, skipping by now
468 */
469 } else
470 spin_unlock_bh(&mpath->state_lock);
471 }
472
473 /* Update and check transmitter routing info */
474 ta = mgmt->sa;
475 if (ether_addr_equal(orig_addr, ta))
476 fresh_info = false;
477 else {
478 fresh_info = true;
479
480 mpath = mesh_path_lookup(sdata, ta);
481 if (mpath) {
482 spin_lock_bh(&mpath->state_lock);
483 if ((mpath->flags & MESH_PATH_FIXED) ||
484 ((mpath->flags & MESH_PATH_ACTIVE) &&
485 (last_hop_metric > mpath->metric)))
486 fresh_info = false;
487 } else {
488 mpath = mesh_path_add(sdata, ta);
489 if (IS_ERR(mpath)) {
490 rcu_read_unlock();
491 return 0;
492 }
493 spin_lock_bh(&mpath->state_lock);
494 }
495
496 if (fresh_info) {
497 mesh_path_assign_nexthop(mpath, sta);
498 mpath->metric = last_hop_metric;
499 mpath->exp_time = time_after(mpath->exp_time, exp_time)
500 ? mpath->exp_time : exp_time;
501 mesh_path_activate(mpath);
502 spin_unlock_bh(&mpath->state_lock);
503 mesh_path_tx_pending(mpath);
504 } else
505 spin_unlock_bh(&mpath->state_lock);
506 }
507
508 rcu_read_unlock();
509
510 return process ? new_metric : 0;
511 }
512
513 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
514 struct ieee80211_mgmt *mgmt,
515 const u8 *preq_elem, u32 metric)
516 {
517 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
518 struct mesh_path *mpath = NULL;
519 const u8 *target_addr, *orig_addr;
520 const u8 *da;
521 u8 target_flags, ttl, flags;
522 u32 orig_sn, target_sn, lifetime, orig_metric;
523 bool reply = false;
524 bool forward = true;
525 bool root_is_gate;
526
527 /* Update target SN, if present */
528 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
529 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
530 target_sn = PREQ_IE_TARGET_SN(preq_elem);
531 orig_sn = PREQ_IE_ORIG_SN(preq_elem);
532 target_flags = PREQ_IE_TARGET_F(preq_elem);
533 orig_metric = metric;
534 /* Proactive PREQ gate announcements */
535 flags = PREQ_IE_FLAGS(preq_elem);
536 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
537
538 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
539
540 if (ether_addr_equal(target_addr, sdata->vif.addr)) {
541 mhwmp_dbg(sdata, "PREQ is for us\n");
542 forward = false;
543 reply = true;
544 metric = 0;
545 if (time_after(jiffies, ifmsh->last_sn_update +
546 net_traversal_jiffies(sdata)) ||
547 time_before(jiffies, ifmsh->last_sn_update)) {
548 target_sn = ++ifmsh->sn;
549 ifmsh->last_sn_update = jiffies;
550 }
551 } else if (is_broadcast_ether_addr(target_addr) &&
552 (target_flags & IEEE80211_PREQ_TO_FLAG)) {
553 rcu_read_lock();
554 mpath = mesh_path_lookup(sdata, orig_addr);
555 if (mpath) {
556 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
557 reply = true;
558 target_addr = sdata->vif.addr;
559 target_sn = ++ifmsh->sn;
560 metric = 0;
561 ifmsh->last_sn_update = jiffies;
562 }
563 if (root_is_gate)
564 mesh_path_add_gate(mpath);
565 }
566 rcu_read_unlock();
567 } else {
568 rcu_read_lock();
569 mpath = mesh_path_lookup(sdata, target_addr);
570 if (mpath) {
571 if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
572 SN_LT(mpath->sn, target_sn)) {
573 mpath->sn = target_sn;
574 mpath->flags |= MESH_PATH_SN_VALID;
575 } else if ((!(target_flags & MP_F_DO)) &&
576 (mpath->flags & MESH_PATH_ACTIVE)) {
577 reply = true;
578 metric = mpath->metric;
579 target_sn = mpath->sn;
580 if (target_flags & MP_F_RF)
581 target_flags |= MP_F_DO;
582 else
583 forward = false;
584 }
585 }
586 rcu_read_unlock();
587 }
588
589 if (reply) {
590 lifetime = PREQ_IE_LIFETIME(preq_elem);
591 ttl = ifmsh->mshcfg.element_ttl;
592 if (ttl != 0) {
593 mhwmp_dbg(sdata, "replying to the PREQ\n");
594 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
595 cpu_to_le32(orig_sn), 0, target_addr,
596 cpu_to_le32(target_sn), mgmt->sa, 0, ttl,
597 cpu_to_le32(lifetime), cpu_to_le32(metric),
598 0, sdata);
599 } else {
600 ifmsh->mshstats.dropped_frames_ttl++;
601 }
602 }
603
604 if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
605 u32 preq_id;
606 u8 hopcount;
607
608 ttl = PREQ_IE_TTL(preq_elem);
609 lifetime = PREQ_IE_LIFETIME(preq_elem);
610 if (ttl <= 1) {
611 ifmsh->mshstats.dropped_frames_ttl++;
612 return;
613 }
614 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
615 --ttl;
616 preq_id = PREQ_IE_PREQ_ID(preq_elem);
617 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
618 da = (mpath && mpath->is_root) ?
619 mpath->rann_snd_addr : broadcast_addr;
620
621 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
622 target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
623 target_sn = PREQ_IE_TARGET_SN(preq_elem);
624 metric = orig_metric;
625 }
626
627 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
628 cpu_to_le32(orig_sn), target_flags, target_addr,
629 cpu_to_le32(target_sn), da,
630 hopcount, ttl, cpu_to_le32(lifetime),
631 cpu_to_le32(metric), cpu_to_le32(preq_id),
632 sdata);
633 if (!is_multicast_ether_addr(da))
634 ifmsh->mshstats.fwded_unicast++;
635 else
636 ifmsh->mshstats.fwded_mcast++;
637 ifmsh->mshstats.fwded_frames++;
638 }
639 }
640
641
642 static inline struct sta_info *
643 next_hop_deref_protected(struct mesh_path *mpath)
644 {
645 return rcu_dereference_protected(mpath->next_hop,
646 lockdep_is_held(&mpath->state_lock));
647 }
648
649
650 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
651 struct ieee80211_mgmt *mgmt,
652 const u8 *prep_elem, u32 metric)
653 {
654 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
655 struct mesh_path *mpath;
656 const u8 *target_addr, *orig_addr;
657 u8 ttl, hopcount, flags;
658 u8 next_hop[ETH_ALEN];
659 u32 target_sn, orig_sn, lifetime;
660
661 mhwmp_dbg(sdata, "received PREP from %pM\n",
662 PREP_IE_TARGET_ADDR(prep_elem));
663
664 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
665 if (ether_addr_equal(orig_addr, sdata->vif.addr))
666 /* destination, no forwarding required */
667 return;
668
669 if (!ifmsh->mshcfg.dot11MeshForwarding)
670 return;
671
672 ttl = PREP_IE_TTL(prep_elem);
673 if (ttl <= 1) {
674 sdata->u.mesh.mshstats.dropped_frames_ttl++;
675 return;
676 }
677
678 rcu_read_lock();
679 mpath = mesh_path_lookup(sdata, orig_addr);
680 if (mpath)
681 spin_lock_bh(&mpath->state_lock);
682 else
683 goto fail;
684 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
685 spin_unlock_bh(&mpath->state_lock);
686 goto fail;
687 }
688 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
689 spin_unlock_bh(&mpath->state_lock);
690 --ttl;
691 flags = PREP_IE_FLAGS(prep_elem);
692 lifetime = PREP_IE_LIFETIME(prep_elem);
693 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
694 target_addr = PREP_IE_TARGET_ADDR(prep_elem);
695 target_sn = PREP_IE_TARGET_SN(prep_elem);
696 orig_sn = PREP_IE_ORIG_SN(prep_elem);
697
698 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr,
699 cpu_to_le32(orig_sn), 0, target_addr,
700 cpu_to_le32(target_sn), next_hop, hopcount,
701 ttl, cpu_to_le32(lifetime), cpu_to_le32(metric),
702 0, sdata);
703 rcu_read_unlock();
704
705 sdata->u.mesh.mshstats.fwded_unicast++;
706 sdata->u.mesh.mshstats.fwded_frames++;
707 return;
708
709 fail:
710 rcu_read_unlock();
711 sdata->u.mesh.mshstats.dropped_frames_no_route++;
712 }
713
714 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
715 struct ieee80211_mgmt *mgmt,
716 const u8 *perr_elem)
717 {
718 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
719 struct mesh_path *mpath;
720 u8 ttl;
721 const u8 *ta, *target_addr;
722 u32 target_sn;
723 u16 target_rcode;
724
725 ta = mgmt->sa;
726 ttl = PERR_IE_TTL(perr_elem);
727 if (ttl <= 1) {
728 ifmsh->mshstats.dropped_frames_ttl++;
729 return;
730 }
731 ttl--;
732 target_addr = PERR_IE_TARGET_ADDR(perr_elem);
733 target_sn = PERR_IE_TARGET_SN(perr_elem);
734 target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
735
736 rcu_read_lock();
737 mpath = mesh_path_lookup(sdata, target_addr);
738 if (mpath) {
739 struct sta_info *sta;
740
741 spin_lock_bh(&mpath->state_lock);
742 sta = next_hop_deref_protected(mpath);
743 if (mpath->flags & MESH_PATH_ACTIVE &&
744 ether_addr_equal(ta, sta->sta.addr) &&
745 (!(mpath->flags & MESH_PATH_SN_VALID) ||
746 SN_GT(target_sn, mpath->sn))) {
747 mpath->flags &= ~MESH_PATH_ACTIVE;
748 mpath->sn = target_sn;
749 spin_unlock_bh(&mpath->state_lock);
750 if (!ifmsh->mshcfg.dot11MeshForwarding)
751 goto endperr;
752 mesh_path_error_tx(sdata, ttl, target_addr,
753 cpu_to_le32(target_sn),
754 cpu_to_le16(target_rcode),
755 broadcast_addr);
756 } else
757 spin_unlock_bh(&mpath->state_lock);
758 }
759 endperr:
760 rcu_read_unlock();
761 }
762
763 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
764 struct ieee80211_mgmt *mgmt,
765 const struct ieee80211_rann_ie *rann)
766 {
767 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
768 struct ieee80211_local *local = sdata->local;
769 struct sta_info *sta;
770 struct mesh_path *mpath;
771 u8 ttl, flags, hopcount;
772 const u8 *orig_addr;
773 u32 orig_sn, metric, metric_txsta, interval;
774 bool root_is_gate;
775
776 ttl = rann->rann_ttl;
777 flags = rann->rann_flags;
778 root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
779 orig_addr = rann->rann_addr;
780 orig_sn = le32_to_cpu(rann->rann_seq);
781 interval = le32_to_cpu(rann->rann_interval);
782 hopcount = rann->rann_hopcount;
783 hopcount++;
784 metric = le32_to_cpu(rann->rann_metric);
785
786 /* Ignore our own RANNs */
787 if (ether_addr_equal(orig_addr, sdata->vif.addr))
788 return;
789
790 mhwmp_dbg(sdata,
791 "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
792 orig_addr, mgmt->sa, root_is_gate);
793
794 rcu_read_lock();
795 sta = sta_info_get(sdata, mgmt->sa);
796 if (!sta) {
797 rcu_read_unlock();
798 return;
799 }
800
801 metric_txsta = airtime_link_metric_get(local, sta);
802
803 mpath = mesh_path_lookup(sdata, orig_addr);
804 if (!mpath) {
805 mpath = mesh_path_add(sdata, orig_addr);
806 if (IS_ERR(mpath)) {
807 rcu_read_unlock();
808 sdata->u.mesh.mshstats.dropped_frames_no_route++;
809 return;
810 }
811 }
812
813 if (!(SN_LT(mpath->sn, orig_sn)) &&
814 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) {
815 rcu_read_unlock();
816 return;
817 }
818
819 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
820 (time_after(jiffies, mpath->last_preq_to_root +
821 root_path_confirmation_jiffies(sdata)) ||
822 time_before(jiffies, mpath->last_preq_to_root))) &&
823 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) {
824 mhwmp_dbg(sdata,
825 "time to refresh root mpath %pM\n",
826 orig_addr);
827 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
828 mpath->last_preq_to_root = jiffies;
829 }
830
831 mpath->sn = orig_sn;
832 mpath->rann_metric = metric + metric_txsta;
833 mpath->is_root = true;
834 /* Recording RANNs sender address to send individually
835 * addressed PREQs destined for root mesh STA */
836 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
837
838 if (root_is_gate)
839 mesh_path_add_gate(mpath);
840
841 if (ttl <= 1) {
842 ifmsh->mshstats.dropped_frames_ttl++;
843 rcu_read_unlock();
844 return;
845 }
846 ttl--;
847
848 if (ifmsh->mshcfg.dot11MeshForwarding) {
849 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
850 cpu_to_le32(orig_sn),
851 0, NULL, 0, broadcast_addr,
852 hopcount, ttl, cpu_to_le32(interval),
853 cpu_to_le32(metric + metric_txsta),
854 0, sdata);
855 }
856
857 rcu_read_unlock();
858 }
859
860
861 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
862 struct ieee80211_mgmt *mgmt, size_t len)
863 {
864 struct ieee802_11_elems elems;
865 size_t baselen;
866 u32 last_hop_metric;
867 struct sta_info *sta;
868
869 /* need action_code */
870 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
871 return;
872
873 rcu_read_lock();
874 sta = sta_info_get(sdata, mgmt->sa);
875 if (!sta || sta->plink_state != NL80211_PLINK_ESTAB) {
876 rcu_read_unlock();
877 return;
878 }
879 rcu_read_unlock();
880
881 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
882 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
883 len - baselen, false, &elems);
884
885 if (elems.preq) {
886 if (elems.preq_len != 37)
887 /* Right now we support just 1 destination and no AE */
888 return;
889 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
890 MPATH_PREQ);
891 if (last_hop_metric)
892 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
893 last_hop_metric);
894 }
895 if (elems.prep) {
896 if (elems.prep_len != 31)
897 /* Right now we support no AE */
898 return;
899 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
900 MPATH_PREP);
901 if (last_hop_metric)
902 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
903 last_hop_metric);
904 }
905 if (elems.perr) {
906 if (elems.perr_len != 15)
907 /* Right now we support only one destination per PERR */
908 return;
909 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
910 }
911 if (elems.rann)
912 hwmp_rann_frame_process(sdata, mgmt, elems.rann);
913 }
914
915 /**
916 * mesh_queue_preq - queue a PREQ to a given destination
917 *
918 * @mpath: mesh path to discover
919 * @flags: special attributes of the PREQ to be sent
920 *
921 * Locking: the function must be called from within a rcu read lock block.
922 *
923 */
924 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
925 {
926 struct ieee80211_sub_if_data *sdata = mpath->sdata;
927 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
928 struct mesh_preq_queue *preq_node;
929
930 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
931 if (!preq_node) {
932 mhwmp_dbg(sdata, "could not allocate PREQ node\n");
933 return;
934 }
935
936 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
937 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
938 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
939 kfree(preq_node);
940 if (printk_ratelimit())
941 mhwmp_dbg(sdata, "PREQ node queue full\n");
942 return;
943 }
944
945 spin_lock(&mpath->state_lock);
946 if (mpath->flags & MESH_PATH_REQ_QUEUED) {
947 spin_unlock(&mpath->state_lock);
948 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
949 kfree(preq_node);
950 return;
951 }
952
953 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
954 preq_node->flags = flags;
955
956 mpath->flags |= MESH_PATH_REQ_QUEUED;
957 spin_unlock(&mpath->state_lock);
958
959 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
960 ++ifmsh->preq_queue_len;
961 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
962
963 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
964 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
965
966 else if (time_before(jiffies, ifmsh->last_preq)) {
967 /* avoid long wait if did not send preqs for a long time
968 * and jiffies wrapped around
969 */
970 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
971 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
972 } else
973 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
974 min_preq_int_jiff(sdata));
975 }
976
977 /**
978 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
979 *
980 * @sdata: local mesh subif
981 */
982 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
983 {
984 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
985 struct mesh_preq_queue *preq_node;
986 struct mesh_path *mpath;
987 u8 ttl, target_flags;
988 const u8 *da;
989 u32 lifetime;
990
991 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
992 if (!ifmsh->preq_queue_len ||
993 time_before(jiffies, ifmsh->last_preq +
994 min_preq_int_jiff(sdata))) {
995 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
996 return;
997 }
998
999 preq_node = list_first_entry(&ifmsh->preq_queue.list,
1000 struct mesh_preq_queue, list);
1001 list_del(&preq_node->list);
1002 --ifmsh->preq_queue_len;
1003 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
1004
1005 rcu_read_lock();
1006 mpath = mesh_path_lookup(sdata, preq_node->dst);
1007 if (!mpath)
1008 goto enddiscovery;
1009
1010 spin_lock_bh(&mpath->state_lock);
1011 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1012 if (preq_node->flags & PREQ_Q_F_START) {
1013 if (mpath->flags & MESH_PATH_RESOLVING) {
1014 spin_unlock_bh(&mpath->state_lock);
1015 goto enddiscovery;
1016 } else {
1017 mpath->flags &= ~MESH_PATH_RESOLVED;
1018 mpath->flags |= MESH_PATH_RESOLVING;
1019 mpath->discovery_retries = 0;
1020 mpath->discovery_timeout = disc_timeout_jiff(sdata);
1021 }
1022 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
1023 mpath->flags & MESH_PATH_RESOLVED) {
1024 mpath->flags &= ~MESH_PATH_RESOLVING;
1025 spin_unlock_bh(&mpath->state_lock);
1026 goto enddiscovery;
1027 }
1028
1029 ifmsh->last_preq = jiffies;
1030
1031 if (time_after(jiffies, ifmsh->last_sn_update +
1032 net_traversal_jiffies(sdata)) ||
1033 time_before(jiffies, ifmsh->last_sn_update)) {
1034 ++ifmsh->sn;
1035 sdata->u.mesh.last_sn_update = jiffies;
1036 }
1037 lifetime = default_lifetime(sdata);
1038 ttl = sdata->u.mesh.mshcfg.element_ttl;
1039 if (ttl == 0) {
1040 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1041 spin_unlock_bh(&mpath->state_lock);
1042 goto enddiscovery;
1043 }
1044
1045 if (preq_node->flags & PREQ_Q_F_REFRESH)
1046 target_flags = MP_F_DO;
1047 else
1048 target_flags = MP_F_RF;
1049
1050 spin_unlock_bh(&mpath->state_lock);
1051 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
1052 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr,
1053 cpu_to_le32(ifmsh->sn), target_flags, mpath->dst,
1054 cpu_to_le32(mpath->sn), da, 0,
1055 ttl, cpu_to_le32(lifetime), 0,
1056 cpu_to_le32(ifmsh->preq_id++), sdata);
1057 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
1058
1059 enddiscovery:
1060 rcu_read_unlock();
1061 kfree(preq_node);
1062 }
1063
1064 /**
1065 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
1066 *
1067 * @skb: 802.11 frame to be sent
1068 * @sdata: network subif the frame will be sent through
1069 *
1070 * Lookup next hop for given skb and start path discovery if no
1071 * forwarding information is found.
1072 *
1073 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
1074 * skb is freeed here if no mpath could be allocated.
1075 */
1076 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
1077 struct sk_buff *skb)
1078 {
1079 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1080 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1081 struct mesh_path *mpath;
1082 struct sk_buff *skb_to_free = NULL;
1083 u8 *target_addr = hdr->addr3;
1084 int err = 0;
1085
1086 /* Nulls are only sent to peers for PS and should be pre-addressed */
1087 if (ieee80211_is_qos_nullfunc(hdr->frame_control))
1088 return 0;
1089
1090 rcu_read_lock();
1091 err = mesh_nexthop_lookup(sdata, skb);
1092 if (!err)
1093 goto endlookup;
1094
1095 /* no nexthop found, start resolving */
1096 mpath = mesh_path_lookup(sdata, target_addr);
1097 if (!mpath) {
1098 mpath = mesh_path_add(sdata, target_addr);
1099 if (IS_ERR(mpath)) {
1100 mesh_path_discard_frame(sdata, skb);
1101 err = PTR_ERR(mpath);
1102 goto endlookup;
1103 }
1104 }
1105
1106 if (!(mpath->flags & MESH_PATH_RESOLVING))
1107 mesh_queue_preq(mpath, PREQ_Q_F_START);
1108
1109 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
1110 skb_to_free = skb_dequeue(&mpath->frame_queue);
1111
1112 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1113 ieee80211_set_qos_hdr(sdata, skb);
1114 skb_queue_tail(&mpath->frame_queue, skb);
1115 err = -ENOENT;
1116 if (skb_to_free)
1117 mesh_path_discard_frame(sdata, skb_to_free);
1118
1119 endlookup:
1120 rcu_read_unlock();
1121 return err;
1122 }
1123
1124 /**
1125 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
1126 * this function is considered "using" the associated mpath, so preempt a path
1127 * refresh if this mpath expires soon.
1128 *
1129 * @skb: 802.11 frame to be sent
1130 * @sdata: network subif the frame will be sent through
1131 *
1132 * Returns: 0 if the next hop was found. Nonzero otherwise.
1133 */
1134 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
1135 struct sk_buff *skb)
1136 {
1137 struct mesh_path *mpath;
1138 struct sta_info *next_hop;
1139 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1140 u8 *target_addr = hdr->addr3;
1141 int err = -ENOENT;
1142
1143 rcu_read_lock();
1144 mpath = mesh_path_lookup(sdata, target_addr);
1145
1146 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
1147 goto endlookup;
1148
1149 if (time_after(jiffies,
1150 mpath->exp_time -
1151 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
1152 ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
1153 !(mpath->flags & MESH_PATH_RESOLVING) &&
1154 !(mpath->flags & MESH_PATH_FIXED))
1155 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
1156
1157 next_hop = rcu_dereference(mpath->next_hop);
1158 if (next_hop) {
1159 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
1160 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
1161 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr);
1162 err = 0;
1163 }
1164
1165 endlookup:
1166 rcu_read_unlock();
1167 return err;
1168 }
1169
1170 void mesh_path_timer(unsigned long data)
1171 {
1172 struct mesh_path *mpath = (void *) data;
1173 struct ieee80211_sub_if_data *sdata = mpath->sdata;
1174 int ret;
1175
1176 if (sdata->local->quiescing)
1177 return;
1178
1179 spin_lock_bh(&mpath->state_lock);
1180 if (mpath->flags & MESH_PATH_RESOLVED ||
1181 (!(mpath->flags & MESH_PATH_RESOLVING))) {
1182 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
1183 spin_unlock_bh(&mpath->state_lock);
1184 } else if (mpath->discovery_retries < max_preq_retries(sdata)) {
1185 ++mpath->discovery_retries;
1186 mpath->discovery_timeout *= 2;
1187 mpath->flags &= ~MESH_PATH_REQ_QUEUED;
1188 spin_unlock_bh(&mpath->state_lock);
1189 mesh_queue_preq(mpath, 0);
1190 } else {
1191 mpath->flags = 0;
1192 mpath->exp_time = jiffies;
1193 spin_unlock_bh(&mpath->state_lock);
1194 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
1195 ret = mesh_path_send_to_gates(mpath);
1196 if (ret)
1197 mhwmp_dbg(sdata, "no gate was reachable\n");
1198 } else
1199 mesh_path_flush_pending(mpath);
1200 }
1201 }
1202
1203 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
1204 {
1205 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1206 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
1207 u8 flags, target_flags = 0;
1208
1209 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
1210 ? RANN_FLAG_IS_GATE : 0;
1211
1212 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
1213 case IEEE80211_PROACTIVE_RANN:
1214 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
1215 cpu_to_le32(++ifmsh->sn),
1216 0, NULL, 0, broadcast_addr,
1217 0, ifmsh->mshcfg.element_ttl,
1218 cpu_to_le32(interval), 0, 0, sdata);
1219 break;
1220 case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
1221 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
1222 case IEEE80211_PROACTIVE_PREQ_NO_PREP:
1223 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
1224 target_flags |= IEEE80211_PREQ_TO_FLAG |
1225 IEEE80211_PREQ_USN_FLAG;
1226 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
1227 cpu_to_le32(++ifmsh->sn), target_flags,
1228 (u8 *) broadcast_addr, 0, broadcast_addr,
1229 0, ifmsh->mshcfg.element_ttl,
1230 cpu_to_le32(interval),
1231 0, cpu_to_le32(ifmsh->preq_id++), sdata);
1232 break;
1233 default:
1234 mhwmp_dbg(sdata, "Proactive mechanism not supported\n");
1235 return;
1236 }
1237 }
Linus' kernel tree