2 * Copyright (c) 2008 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
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.
12 #ifdef CONFIG_MAC80211_VERBOSE_MHWMP_DEBUG
13 #define mhwmp_dbg(fmt, args...) printk(KERN_DEBUG "Mesh HWMP: " fmt, ##args)
15 #define mhwmp_dbg(fmt, args...) do { (void)(0); } while (0)
18 #define TEST_FRAME_LEN 8192
19 #define MAX_METRIC 0xffffffff
22 /* Number of frames buffered per destination for unresolved destinations */
23 #define MESH_FRAME_QUEUE_LEN 10
24 #define MAX_PREQ_QUEUE_LEN 64
26 /* Destination only */
28 /* Reply and forward */
31 static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae)
35 return get_unaligned_le32(preq_elem + offset);
38 /* HWMP IE processing macros */
40 #define AE_F_SET(x) (*x & AE_F)
41 #define PREQ_IE_FLAGS(x) (*(x))
42 #define PREQ_IE_HOPCOUNT(x) (*(x + 1))
43 #define PREQ_IE_TTL(x) (*(x + 2))
44 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
45 #define PREQ_IE_ORIG_ADDR(x) (x + 7)
46 #define PREQ_IE_ORIG_DSN(x) u32_field_get(x, 13, 0);
47 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x));
48 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x));
49 #define PREQ_IE_DST_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
50 #define PREQ_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
51 #define PREQ_IE_DST_DSN(x) u32_field_get(x, 33, AE_F_SET(x));
54 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
55 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
56 #define PREP_IE_TTL(x) PREQ_IE_TTL(x)
57 #define PREP_IE_ORIG_ADDR(x) (x + 3)
58 #define PREP_IE_ORIG_DSN(x) u32_field_get(x, 9, 0);
59 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x));
60 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x));
61 #define PREP_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
62 #define PREP_IE_DST_DSN(x) u32_field_get(x, 27, AE_F_SET(x));
64 #define PERR_IE_DST_ADDR(x) (x + 2)
65 #define PERR_IE_DST_DSN(x) u32_field_get(x, 8, 0);
67 #define MSEC_TO_TU(x) (x*1000/1024)
68 #define DSN_GT(x, y) ((long) (y) - (long) (x) < 0)
69 #define DSN_LT(x, y) ((long) (x) - (long) (y) < 0)
71 #define net_traversal_jiffies(s) \
72 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
73 #define default_lifetime(s) \
74 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout)
75 #define min_preq_int_jiff(s) \
76 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval))
77 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries)
78 #define disc_timeout_jiff(s) \
79 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout)
81 enum mpath_frame_type {
87 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
88 u8 *orig_addr, __le32 orig_dsn, u8 dst_flags, u8 *dst,
89 __le32 dst_dsn, u8 *da, u8 hop_count, u8 ttl, __le32 lifetime,
90 __le32 metric, __le32 preq_id, struct ieee80211_sub_if_data *sdata)
92 struct ieee80211_local *local = sdata->local;
93 struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
94 struct ieee80211_mgmt *mgmt;
100 skb_reserve(skb, local->hw.extra_tx_headroom);
101 /* 25 is the size of the common mgmt part (24) plus the size of the
102 * common action part (1)
104 mgmt = (struct ieee80211_mgmt *)
105 skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action));
106 memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action));
107 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
108 IEEE80211_STYPE_ACTION);
110 memcpy(mgmt->da, da, ETH_ALEN);
111 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
112 /* BSSID is left zeroed, wildcard value */
113 mgmt->u.action.category = MESH_PATH_SEL_CATEGORY;
114 mgmt->u.action.u.mesh_action.action_code = MESH_PATH_SEL_ACTION;
118 mhwmp_dbg("sending PREQ\n");
120 pos = skb_put(skb, 2 + ie_len);
121 *pos++ = WLAN_EID_PREQ;
124 mhwmp_dbg("sending PREP\n");
126 pos = skb_put(skb, 2 + ie_len);
127 *pos++ = WLAN_EID_PREP;
138 if (action == MPATH_PREQ) {
139 memcpy(pos, &preq_id, 4);
142 memcpy(pos, orig_addr, ETH_ALEN);
144 memcpy(pos, &orig_dsn, 4);
146 memcpy(pos, &lifetime, 4);
148 memcpy(pos, &metric, 4);
150 if (action == MPATH_PREQ) {
151 /* destination count */
155 memcpy(pos, dst, ETH_ALEN);
157 memcpy(pos, &dst_dsn, 4);
159 ieee80211_tx_skb(sdata, skb, 1);
164 * mesh_send_path error - Sends a PERR mesh management frame
166 * @dst: broken destination
167 * @dst_dsn: dsn of the broken destination
168 * @ra: node this frame is addressed to
170 int mesh_path_error_tx(u8 *dst, __le32 dst_dsn, u8 *ra,
171 struct ieee80211_sub_if_data *sdata)
173 struct ieee80211_local *local = sdata->local;
174 struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
175 struct ieee80211_mgmt *mgmt;
181 skb_reserve(skb, local->hw.extra_tx_headroom);
182 /* 25 is the size of the common mgmt part (24) plus the size of the
183 * common action part (1)
185 mgmt = (struct ieee80211_mgmt *)
186 skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action));
187 memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action));
188 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
189 IEEE80211_STYPE_ACTION);
191 memcpy(mgmt->da, ra, ETH_ALEN);
192 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
193 /* BSSID is left zeroed, wildcard value */
194 mgmt->u.action.category = MESH_PATH_SEL_CATEGORY;
195 mgmt->u.action.u.mesh_action.action_code = MESH_PATH_SEL_ACTION;
197 pos = skb_put(skb, 2 + ie_len);
198 *pos++ = WLAN_EID_PERR;
200 /* mode flags, reserved */
202 /* number of destinations */
204 memcpy(pos, dst, ETH_ALEN);
206 memcpy(pos, &dst_dsn, 4);
208 ieee80211_tx_skb(sdata, skb, 1);
212 void ieee80211s_update_metric(struct ieee80211_local *local,
213 struct sta_info *stainfo, struct sk_buff *skb)
215 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
216 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
219 if (!ieee80211_is_data(hdr->frame_control))
222 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
224 /* moving average, scaled to 100 */
225 stainfo->fail_avg = ((80 * stainfo->fail_avg + 5) / 100 + 20 * failed);
226 if (stainfo->fail_avg > 95)
227 mesh_plink_broken(stainfo);
230 static u32 airtime_link_metric_get(struct ieee80211_local *local,
231 struct sta_info *sta)
233 struct ieee80211_supported_band *sband;
234 /* This should be adjusted for each device */
235 int device_constant = 1 << ARITH_SHIFT;
236 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
237 int s_unit = 1 << ARITH_SHIFT;
239 u32 tx_time, estimated_retx;
242 sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
244 if (sta->fail_avg >= 100)
247 if (sta->last_tx_rate.flags & IEEE80211_TX_RC_MCS)
250 err = (sta->fail_avg << ARITH_SHIFT) / 100;
252 /* bitrate is in units of 100 Kbps, while we need rate in units of
253 * 1Mbps. This will be corrected on tx_time computation.
255 rate = sband->bitrates[sta->last_tx_rate.idx].bitrate;
256 tx_time = (device_constant + 10 * test_frame_len / rate);
257 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
258 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ;
263 * hwmp_route_info_get - Update routing info to originator and transmitter
265 * @sdata: local mesh subif
266 * @mgmt: mesh management frame
267 * @hwmp_ie: hwmp information element (PREP or PREQ)
269 * This function updates the path routing information to the originator and the
270 * transmitter of a HWMP PREQ or PREP frame.
272 * Returns: metric to frame originator or 0 if the frame should not be further
275 * Notes: this function is the only place (besides user-provided info) where
276 * path routing information is updated.
278 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
279 struct ieee80211_mgmt *mgmt,
280 u8 *hwmp_ie, enum mpath_frame_type action)
282 struct ieee80211_local *local = sdata->local;
283 struct mesh_path *mpath;
284 struct sta_info *sta;
287 u32 orig_dsn, orig_metric;
288 unsigned long orig_lifetime, exp_time;
289 u32 last_hop_metric, new_metric;
293 sta = sta_info_get(local, mgmt->sa);
299 last_hop_metric = airtime_link_metric_get(local, sta);
300 /* Update and check originator routing info */
305 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
306 orig_dsn = PREQ_IE_ORIG_DSN(hwmp_ie);
307 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
308 orig_metric = PREQ_IE_METRIC(hwmp_ie);
311 /* Originator here refers to the MP that was the destination in
312 * the Path Request. The draft refers to that MP as the
313 * destination address, even though usually it is the origin of
314 * the PREP frame. We divert from the nomenclature in the draft
315 * so that we can easily use a single function to gather path
316 * information from both PREQ and PREP frames.
318 orig_addr = PREP_IE_ORIG_ADDR(hwmp_ie);
319 orig_dsn = PREP_IE_ORIG_DSN(hwmp_ie);
320 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
321 orig_metric = PREP_IE_METRIC(hwmp_ie);
327 new_metric = orig_metric + last_hop_metric;
328 if (new_metric < orig_metric)
329 new_metric = MAX_METRIC;
330 exp_time = TU_TO_EXP_TIME(orig_lifetime);
332 if (memcmp(orig_addr, sdata->dev->dev_addr, ETH_ALEN) == 0) {
333 /* This MP is the originator, we are not interested in this
334 * frame, except for updating transmitter's path info.
339 mpath = mesh_path_lookup(orig_addr, sdata);
341 spin_lock_bh(&mpath->state_lock);
342 if (mpath->flags & MESH_PATH_FIXED)
344 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
345 (mpath->flags & MESH_PATH_DSN_VALID)) {
346 if (DSN_GT(mpath->dsn, orig_dsn) ||
347 (mpath->dsn == orig_dsn &&
348 action == MPATH_PREQ &&
349 new_metric > mpath->metric)) {
355 mesh_path_add(orig_addr, sdata);
356 mpath = mesh_path_lookup(orig_addr, sdata);
361 spin_lock_bh(&mpath->state_lock);
365 mesh_path_assign_nexthop(mpath, sta);
366 mpath->flags |= MESH_PATH_DSN_VALID;
367 mpath->metric = new_metric;
368 mpath->dsn = orig_dsn;
369 mpath->exp_time = time_after(mpath->exp_time, exp_time)
370 ? mpath->exp_time : exp_time;
371 mesh_path_activate(mpath);
372 spin_unlock_bh(&mpath->state_lock);
373 mesh_path_tx_pending(mpath);
374 /* draft says preq_id should be saved to, but there does
375 * not seem to be any use for it, skipping by now
378 spin_unlock_bh(&mpath->state_lock);
381 /* Update and check transmitter routing info */
383 if (memcmp(orig_addr, ta, ETH_ALEN) == 0)
388 mpath = mesh_path_lookup(ta, sdata);
390 spin_lock_bh(&mpath->state_lock);
391 if ((mpath->flags & MESH_PATH_FIXED) ||
392 ((mpath->flags & MESH_PATH_ACTIVE) &&
393 (last_hop_metric > mpath->metric)))
396 mesh_path_add(ta, sdata);
397 mpath = mesh_path_lookup(ta, sdata);
402 spin_lock_bh(&mpath->state_lock);
406 mesh_path_assign_nexthop(mpath, sta);
407 mpath->flags &= ~MESH_PATH_DSN_VALID;
408 mpath->metric = last_hop_metric;
409 mpath->exp_time = time_after(mpath->exp_time, exp_time)
410 ? mpath->exp_time : exp_time;
411 mesh_path_activate(mpath);
412 spin_unlock_bh(&mpath->state_lock);
413 mesh_path_tx_pending(mpath);
415 spin_unlock_bh(&mpath->state_lock);
420 return process ? new_metric : 0;
423 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
424 struct ieee80211_mgmt *mgmt,
425 u8 *preq_elem, u32 metric)
427 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
428 struct mesh_path *mpath;
429 u8 *dst_addr, *orig_addr;
431 u32 orig_dsn, dst_dsn, lifetime;
435 /* Update destination DSN, if present */
436 dst_addr = PREQ_IE_DST_ADDR(preq_elem);
437 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
438 dst_dsn = PREQ_IE_DST_DSN(preq_elem);
439 orig_dsn = PREQ_IE_ORIG_DSN(preq_elem);
440 dst_flags = PREQ_IE_DST_F(preq_elem);
442 mhwmp_dbg("received PREQ\n");
444 if (memcmp(dst_addr, sdata->dev->dev_addr, ETH_ALEN) == 0) {
445 mhwmp_dbg("PREQ is for us\n");
449 if (time_after(jiffies, ifmsh->last_dsn_update +
450 net_traversal_jiffies(sdata)) ||
451 time_before(jiffies, ifmsh->last_dsn_update)) {
452 dst_dsn = ++ifmsh->dsn;
453 ifmsh->last_dsn_update = jiffies;
457 mpath = mesh_path_lookup(dst_addr, sdata);
459 if ((!(mpath->flags & MESH_PATH_DSN_VALID)) ||
460 DSN_LT(mpath->dsn, dst_dsn)) {
461 mpath->dsn = dst_dsn;
462 mpath->flags |= MESH_PATH_DSN_VALID;
463 } else if ((!(dst_flags & MP_F_DO)) &&
464 (mpath->flags & MESH_PATH_ACTIVE)) {
466 metric = mpath->metric;
467 dst_dsn = mpath->dsn;
468 if (dst_flags & MP_F_RF)
469 dst_flags |= MP_F_DO;
478 lifetime = PREQ_IE_LIFETIME(preq_elem);
479 ttl = ifmsh->mshcfg.dot11MeshTTL;
481 mhwmp_dbg("replying to the PREQ\n");
482 mesh_path_sel_frame_tx(MPATH_PREP, 0, dst_addr,
483 cpu_to_le32(dst_dsn), 0, orig_addr,
484 cpu_to_le32(orig_dsn), mgmt->sa, 0, ttl,
485 cpu_to_le32(lifetime), cpu_to_le32(metric),
488 ifmsh->mshstats.dropped_frames_ttl++;
495 ttl = PREQ_IE_TTL(preq_elem);
496 lifetime = PREQ_IE_LIFETIME(preq_elem);
498 ifmsh->mshstats.dropped_frames_ttl++;
501 mhwmp_dbg("forwarding the PREQ\n");
503 flags = PREQ_IE_FLAGS(preq_elem);
504 preq_id = PREQ_IE_PREQ_ID(preq_elem);
505 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
506 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
507 cpu_to_le32(orig_dsn), dst_flags, dst_addr,
508 cpu_to_le32(dst_dsn), sdata->dev->broadcast,
509 hopcount, ttl, cpu_to_le32(lifetime),
510 cpu_to_le32(metric), cpu_to_le32(preq_id),
512 ifmsh->mshstats.fwded_mcast++;
513 ifmsh->mshstats.fwded_frames++;
518 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
519 struct ieee80211_mgmt *mgmt,
520 u8 *prep_elem, u32 metric)
522 struct mesh_path *mpath;
523 u8 *dst_addr, *orig_addr;
524 u8 ttl, hopcount, flags;
525 u8 next_hop[ETH_ALEN];
526 u32 dst_dsn, orig_dsn, lifetime;
528 mhwmp_dbg("received PREP\n");
530 /* Note that we divert from the draft nomenclature and denominate
531 * destination to what the draft refers to as origininator. So in this
532 * function destnation refers to the final destination of the PREP,
533 * which corresponds with the originator of the PREQ which this PREP
536 dst_addr = PREP_IE_DST_ADDR(prep_elem);
537 if (memcmp(dst_addr, sdata->dev->dev_addr, ETH_ALEN) == 0)
538 /* destination, no forwarding required */
541 ttl = PREP_IE_TTL(prep_elem);
543 sdata->u.mesh.mshstats.dropped_frames_ttl++;
548 mpath = mesh_path_lookup(dst_addr, sdata);
550 spin_lock_bh(&mpath->state_lock);
553 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
554 spin_unlock_bh(&mpath->state_lock);
557 memcpy(next_hop, mpath->next_hop->sta.addr, ETH_ALEN);
558 spin_unlock_bh(&mpath->state_lock);
560 flags = PREP_IE_FLAGS(prep_elem);
561 lifetime = PREP_IE_LIFETIME(prep_elem);
562 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
563 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
564 dst_dsn = PREP_IE_DST_DSN(prep_elem);
565 orig_dsn = PREP_IE_ORIG_DSN(prep_elem);
567 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr,
568 cpu_to_le32(orig_dsn), 0, dst_addr,
569 cpu_to_le32(dst_dsn), mpath->next_hop->sta.addr, hopcount, ttl,
570 cpu_to_le32(lifetime), cpu_to_le32(metric),
574 sdata->u.mesh.mshstats.fwded_unicast++;
575 sdata->u.mesh.mshstats.fwded_frames++;
580 sdata->u.mesh.mshstats.dropped_frames_no_route++;
584 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
585 struct ieee80211_mgmt *mgmt, u8 *perr_elem)
587 struct mesh_path *mpath;
592 dst_addr = PERR_IE_DST_ADDR(perr_elem);
593 dst_dsn = PERR_IE_DST_DSN(perr_elem);
595 mpath = mesh_path_lookup(dst_addr, sdata);
597 spin_lock_bh(&mpath->state_lock);
598 if (mpath->flags & MESH_PATH_ACTIVE &&
599 memcmp(ta, mpath->next_hop->sta.addr, ETH_ALEN) == 0 &&
600 (!(mpath->flags & MESH_PATH_DSN_VALID) ||
601 DSN_GT(dst_dsn, mpath->dsn))) {
602 mpath->flags &= ~MESH_PATH_ACTIVE;
603 mpath->dsn = dst_dsn;
604 spin_unlock_bh(&mpath->state_lock);
605 mesh_path_error_tx(dst_addr, cpu_to_le32(dst_dsn),
606 sdata->dev->broadcast, sdata);
608 spin_unlock_bh(&mpath->state_lock);
615 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
616 struct ieee80211_mgmt *mgmt,
619 struct ieee802_11_elems elems;
623 /* need action_code */
624 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
627 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
628 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
629 len - baselen, &elems);
631 mhwmp_dbg("RX path selection frame\n");
633 if (elems.preq_len != 37)
634 /* Right now we support just 1 destination and no AE */
636 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
639 hwmp_preq_frame_process(sdata, mgmt, elems.preq,
643 if (elems.prep_len != 31)
644 /* Right now we support no AE */
646 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
649 hwmp_prep_frame_process(sdata, mgmt, elems.prep,
653 if (elems.perr_len != 12)
654 /* Right now we support only one destination per PERR */
656 hwmp_perr_frame_process(sdata, mgmt, elems.perr);
662 * mesh_queue_preq - queue a PREQ to a given destination
664 * @mpath: mesh path to discover
665 * @flags: special attributes of the PREQ to be sent
667 * Locking: the function must be called from within a rcu read lock block.
670 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
672 struct ieee80211_sub_if_data *sdata = mpath->sdata;
673 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
674 struct mesh_preq_queue *preq_node;
676 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
678 mhwmp_dbg("could not allocate PREQ node\n");
682 spin_lock(&ifmsh->mesh_preq_queue_lock);
683 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
684 spin_unlock(&ifmsh->mesh_preq_queue_lock);
686 if (printk_ratelimit())
687 mhwmp_dbg("PREQ node queue full\n");
691 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
692 preq_node->flags = flags;
694 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
695 ++ifmsh->preq_queue_len;
696 spin_unlock(&ifmsh->mesh_preq_queue_lock);
698 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
699 ieee80211_queue_work(&sdata->local->hw, &ifmsh->work);
701 else if (time_before(jiffies, ifmsh->last_preq)) {
702 /* avoid long wait if did not send preqs for a long time
703 * and jiffies wrapped around
705 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
706 ieee80211_queue_work(&sdata->local->hw, &ifmsh->work);
708 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
709 min_preq_int_jiff(sdata));
713 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
715 * @sdata: local mesh subif
717 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
719 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
720 struct mesh_preq_queue *preq_node;
721 struct mesh_path *mpath;
725 spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
726 if (!ifmsh->preq_queue_len ||
727 time_before(jiffies, ifmsh->last_preq +
728 min_preq_int_jiff(sdata))) {
729 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
733 preq_node = list_first_entry(&ifmsh->preq_queue.list,
734 struct mesh_preq_queue, list);
735 list_del(&preq_node->list);
736 --ifmsh->preq_queue_len;
737 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
740 mpath = mesh_path_lookup(preq_node->dst, sdata);
744 spin_lock_bh(&mpath->state_lock);
745 if (preq_node->flags & PREQ_Q_F_START) {
746 if (mpath->flags & MESH_PATH_RESOLVING) {
747 spin_unlock_bh(&mpath->state_lock);
750 mpath->flags &= ~MESH_PATH_RESOLVED;
751 mpath->flags |= MESH_PATH_RESOLVING;
752 mpath->discovery_retries = 0;
753 mpath->discovery_timeout = disc_timeout_jiff(sdata);
755 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
756 mpath->flags & MESH_PATH_RESOLVED) {
757 mpath->flags &= ~MESH_PATH_RESOLVING;
758 spin_unlock_bh(&mpath->state_lock);
762 ifmsh->last_preq = jiffies;
764 if (time_after(jiffies, ifmsh->last_dsn_update +
765 net_traversal_jiffies(sdata)) ||
766 time_before(jiffies, ifmsh->last_dsn_update)) {
768 sdata->u.mesh.last_dsn_update = jiffies;
770 lifetime = default_lifetime(sdata);
771 ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
773 sdata->u.mesh.mshstats.dropped_frames_ttl++;
774 spin_unlock_bh(&mpath->state_lock);
778 if (preq_node->flags & PREQ_Q_F_REFRESH)
783 spin_unlock_bh(&mpath->state_lock);
784 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->dev->dev_addr,
785 cpu_to_le32(ifmsh->dsn), dst_flags, mpath->dst,
786 cpu_to_le32(mpath->dsn), sdata->dev->broadcast, 0,
787 ttl, cpu_to_le32(lifetime), 0,
788 cpu_to_le32(ifmsh->preq_id++), sdata);
789 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
797 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame
799 * @skb: 802.11 frame to be sent
800 * @sdata: network subif the frame will be sent through
802 * Returns: 0 if the next hop was found. Nonzero otherwise. If no next hop is
803 * found, the function will start a path discovery and queue the frame so it is
804 * sent when the path is resolved. This means the caller must not free the skb
807 int mesh_nexthop_lookup(struct sk_buff *skb,
808 struct ieee80211_sub_if_data *sdata)
810 struct sk_buff *skb_to_free = NULL;
811 struct mesh_path *mpath;
812 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
813 u8 *dst_addr = hdr->addr3;
817 mpath = mesh_path_lookup(dst_addr, sdata);
820 mesh_path_add(dst_addr, sdata);
821 mpath = mesh_path_lookup(dst_addr, sdata);
823 sdata->u.mesh.mshstats.dropped_frames_no_route++;
829 if (mpath->flags & MESH_PATH_ACTIVE) {
830 if (time_after(jiffies, mpath->exp_time +
831 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time))
832 && !memcmp(sdata->dev->dev_addr, hdr->addr4,
834 && !(mpath->flags & MESH_PATH_RESOLVING)
835 && !(mpath->flags & MESH_PATH_FIXED)) {
836 mesh_queue_preq(mpath,
837 PREQ_Q_F_START | PREQ_Q_F_REFRESH);
839 memcpy(hdr->addr1, mpath->next_hop->sta.addr,
842 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
843 if (!(mpath->flags & MESH_PATH_RESOLVING)) {
844 /* Start discovery only if it is not running yet */
845 mesh_queue_preq(mpath, PREQ_Q_F_START);
848 if (skb_queue_len(&mpath->frame_queue) >=
849 MESH_FRAME_QUEUE_LEN)
850 skb_to_free = skb_dequeue(&mpath->frame_queue);
852 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
853 skb_queue_tail(&mpath->frame_queue, skb);
855 mesh_path_discard_frame(skb_to_free, sdata);
864 void mesh_path_timer(unsigned long data)
866 struct ieee80211_sub_if_data *sdata;
867 struct mesh_path *mpath;
870 mpath = (struct mesh_path *) data;
871 mpath = rcu_dereference(mpath);
874 sdata = mpath->sdata;
876 if (sdata->local->quiescing) {
881 spin_lock_bh(&mpath->state_lock);
882 if (mpath->flags & MESH_PATH_RESOLVED ||
883 (!(mpath->flags & MESH_PATH_RESOLVING)))
884 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
885 else if (mpath->discovery_retries < max_preq_retries(sdata)) {
886 ++mpath->discovery_retries;
887 mpath->discovery_timeout *= 2;
888 mesh_queue_preq(mpath, 0);
891 mpath->exp_time = jiffies;
892 mesh_path_flush_pending(mpath);
895 spin_unlock_bh(&mpath->state_lock);