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.
10 #include <asm/unaligned.h>
13 #define IEEE80211_FC(type, stype) cpu_to_le16(type | stype)
15 #define TEST_FRAME_LEN 8192
16 #define MAX_METRIC 0xffffffff
19 /* Number of frames buffered per destination for unresolved destinations */
20 #define MESH_FRAME_QUEUE_LEN 10
21 #define MAX_PREQ_QUEUE_LEN 64
23 /* Destination only */
25 /* Reply and forward */
28 static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae)
32 return le32_to_cpu(get_unaligned((__le32 *) (preq_elem + offset)));
35 /* HWMP IE processing macros */
37 #define AE_F_SET(x) (*x & AE_F)
38 #define PREQ_IE_FLAGS(x) (*(x))
39 #define PREQ_IE_HOPCOUNT(x) (*(x + 1))
40 #define PREQ_IE_TTL(x) (*(x + 2))
41 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
42 #define PREQ_IE_ORIG_ADDR(x) (x + 7)
43 #define PREQ_IE_ORIG_DSN(x) u32_field_get(x, 13, 0);
44 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x));
45 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x));
46 #define PREQ_IE_DST_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
47 #define PREQ_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
48 #define PREQ_IE_DST_DSN(x) u32_field_get(x, 33, AE_F_SET(x));
51 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
52 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
53 #define PREP_IE_TTL(x) PREQ_IE_TTL(x)
54 #define PREP_IE_ORIG_ADDR(x) (x + 3)
55 #define PREP_IE_ORIG_DSN(x) u32_field_get(x, 9, 0);
56 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x));
57 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x));
58 #define PREP_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
59 #define PREP_IE_DST_DSN(x) u32_field_get(x, 27, AE_F_SET(x));
61 #define PERR_IE_DST_ADDR(x) (x + 2)
62 #define PERR_IE_DST_DSN(x) u32_field_get(x, 8, 0);
64 #define TU_TO_EXP_TIME(x) (jiffies + msecs_to_jiffies(x * 1024 / 1000))
65 #define MSEC_TO_TU(x) (x*1000/1024)
66 #define DSN_GT(x, y) ((long) (y) - (long) (x) < 0)
67 #define DSN_LT(x, y) ((long) (x) - (long) (y) < 0)
69 #define net_traversal_jiffies(s) \
70 msecs_to_jiffies(s->u.sta.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
71 #define default_lifetime(s) \
72 MSEC_TO_TU(s->u.sta.mshcfg.dot11MeshHWMPactivePathTimeout)
73 #define min_preq_int_jiff(s) \
74 (msecs_to_jiffies(s->u.sta.mshcfg.dot11MeshHWMPpreqMinInterval))
75 #define max_preq_retries(s) (s->u.sta.mshcfg.dot11MeshHWMPmaxPREQretries)
76 #define disc_timeout_jiff(s) \
77 msecs_to_jiffies(sdata->u.sta.mshcfg.min_discovery_timeout)
79 enum mpath_frame_type {
85 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
86 u8 *orig_addr, __le32 orig_dsn, u8 dst_flags, u8 *dst,
87 __le32 dst_dsn, u8 *da, u8 hop_count, u8 ttl, __le32 lifetime,
88 __le32 metric, __le32 preq_id, struct net_device *dev)
90 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
91 struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
92 struct ieee80211_mgmt *mgmt;
98 skb_reserve(skb, local->hw.extra_tx_headroom);
99 /* 25 is the size of the common mgmt part (24) plus the size of the
100 * common action part (1)
102 mgmt = (struct ieee80211_mgmt *)
103 skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action));
104 memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action));
105 mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
106 IEEE80211_STYPE_ACTION);
108 memcpy(mgmt->da, da, ETH_ALEN);
109 memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN);
110 /* BSSID is left zeroed, wildcard value */
111 mgmt->u.action.category = MESH_PATH_SEL_CATEGORY;
112 mgmt->u.action.u.mesh_action.action_code = action;
117 pos = skb_put(skb, 2 + ie_len);
118 *pos++ = WLAN_EID_PREQ;
122 pos = skb_put(skb, 2 + ie_len);
123 *pos++ = WLAN_EID_PREP;
134 if (action == MPATH_PREQ) {
135 memcpy(pos, &preq_id, 4);
138 memcpy(pos, orig_addr, ETH_ALEN);
140 memcpy(pos, &orig_dsn, 4);
142 memcpy(pos, &lifetime, 4);
144 memcpy(pos, &metric, 4);
146 if (action == MPATH_PREQ) {
147 /* destination count */
151 memcpy(pos, dst, ETH_ALEN);
153 memcpy(pos, &dst_dsn, 4);
155 ieee80211_sta_tx(dev, skb, 0);
160 * mesh_send_path error - Sends a PERR mesh management frame
162 * @dst: broken destination
163 * @dst_dsn: dsn of the broken destination
164 * @ra: node this frame is addressed to
166 int mesh_path_error_tx(u8 *dst, __le32 dst_dsn, u8 *ra,
167 struct net_device *dev)
169 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
170 struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
171 struct ieee80211_mgmt *mgmt;
177 skb_reserve(skb, local->hw.extra_tx_headroom);
178 /* 25 is the size of the common mgmt part (24) plus the size of the
179 * common action part (1)
181 mgmt = (struct ieee80211_mgmt *)
182 skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action));
183 memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action));
184 mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
185 IEEE80211_STYPE_ACTION);
187 memcpy(mgmt->da, ra, ETH_ALEN);
188 memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN);
189 /* BSSID is left zeroed, wildcard value */
190 mgmt->u.action.category = MESH_PATH_SEL_CATEGORY;
191 mgmt->u.action.u.mesh_action.action_code = MPATH_PERR;
193 pos = skb_put(skb, 2 + ie_len);
194 *pos++ = WLAN_EID_PERR;
196 /* mode flags, reserved */
198 /* number of destinations */
200 memcpy(pos, dst, ETH_ALEN);
202 memcpy(pos, &dst_dsn, 4);
204 ieee80211_sta_tx(dev, skb, 0);
208 static u32 airtime_link_metric_get(struct ieee80211_local *local,
209 struct sta_info *sta)
211 struct ieee80211_supported_band *sband;
212 /* This should be adjusted for each device */
213 int device_constant = 1 << ARITH_SHIFT;
214 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
215 int s_unit = 1 << ARITH_SHIFT;
217 u32 tx_time, estimated_retx;
220 sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
222 if (sta->fail_avg >= 100)
224 err = (sta->fail_avg << ARITH_SHIFT) / 100;
226 /* bitrate is in units of 100 Kbps, while we need rate in units of
227 * 1Mbps. This will be corrected on tx_time computation.
229 rate = sband->bitrates[sta->txrate_idx].bitrate;
230 tx_time = (device_constant + 10 * test_frame_len / rate);
231 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
232 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ;
237 * hwmp_route_info_get - Update routing info to originator and transmitter
239 * @dev: local mesh interface
240 * @mgmt: mesh management frame
241 * @hwmp_ie: hwmp information element (PREP or PREQ)
243 * This function updates the path routing information to the originator and the
244 * transmitter of a HWMP PREQ or PREP fram.
246 * Returns: metric to frame originator or 0 if the frame should not be further
249 * Notes: this function is the only place (besides user-provided info) where
250 * path routing information is updated.
252 static u32 hwmp_route_info_get(struct net_device *dev,
253 struct ieee80211_mgmt *mgmt,
256 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
257 struct mesh_path *mpath;
258 struct sta_info *sta;
261 u32 orig_dsn, orig_metric;
262 unsigned long orig_lifetime, exp_time;
263 u32 last_hop_metric, new_metric;
265 u8 action = mgmt->u.action.u.mesh_action.action_code;
268 sta = sta_info_get(local, mgmt->sa);
274 last_hop_metric = airtime_link_metric_get(local, sta);
275 /* Update and check originator routing info */
280 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
281 orig_dsn = PREQ_IE_ORIG_DSN(hwmp_ie);
282 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
283 orig_metric = PREQ_IE_METRIC(hwmp_ie);
286 /* Originator here refers to the MP that was the destination in
287 * the Path Request. The draft refers to that MP as the
288 * destination address, even though usually it is the origin of
289 * the PREP frame. We divert from the nomenclature in the draft
290 * so that we can easily use a single function to gather path
291 * information from both PREQ and PREP frames.
293 orig_addr = PREP_IE_ORIG_ADDR(hwmp_ie);
294 orig_dsn = PREP_IE_ORIG_DSN(hwmp_ie);
295 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
296 orig_metric = PREP_IE_METRIC(hwmp_ie);
302 new_metric = orig_metric + last_hop_metric;
303 if (new_metric < orig_metric)
304 new_metric = MAX_METRIC;
305 exp_time = TU_TO_EXP_TIME(orig_lifetime);
307 if (memcmp(orig_addr, dev->dev_addr, ETH_ALEN) == 0) {
308 /* This MP is the originator, we are not interested in this
309 * frame, except for updating transmitter's path info.
314 mpath = mesh_path_lookup(orig_addr, dev);
316 spin_lock_bh(&mpath->state_lock);
317 if (mpath->flags & MESH_PATH_FIXED)
319 else if ((mpath->flags & MESH_PATH_ACTIVE) &&
320 (mpath->flags & MESH_PATH_DSN_VALID)) {
321 if (DSN_GT(mpath->dsn, orig_dsn) ||
322 (mpath->dsn == orig_dsn &&
323 action == MPATH_PREQ &&
324 new_metric > mpath->metric)) {
330 mesh_path_add(orig_addr, dev);
331 mpath = mesh_path_lookup(orig_addr, dev);
336 spin_lock_bh(&mpath->state_lock);
340 mesh_path_assign_nexthop(mpath, sta);
341 mpath->flags |= MESH_PATH_DSN_VALID;
342 mpath->metric = new_metric;
343 mpath->dsn = orig_dsn;
344 mpath->exp_time = time_after(mpath->exp_time, exp_time)
345 ? mpath->exp_time : exp_time;
346 mesh_path_activate(mpath);
347 spin_unlock_bh(&mpath->state_lock);
348 mesh_path_tx_pending(mpath);
349 /* draft says preq_id should be saved to, but there does
350 * not seem to be any use for it, skipping by now
353 spin_unlock_bh(&mpath->state_lock);
356 /* Update and check transmitter routing info */
358 if (memcmp(orig_addr, ta, ETH_ALEN) == 0)
363 mpath = mesh_path_lookup(ta, dev);
365 spin_lock_bh(&mpath->state_lock);
366 if ((mpath->flags & MESH_PATH_FIXED) ||
367 ((mpath->flags & MESH_PATH_ACTIVE) &&
368 (last_hop_metric > mpath->metric)))
371 mesh_path_add(ta, dev);
372 mpath = mesh_path_lookup(ta, dev);
377 spin_lock_bh(&mpath->state_lock);
381 mesh_path_assign_nexthop(mpath, sta);
382 mpath->flags &= ~MESH_PATH_DSN_VALID;
383 mpath->metric = last_hop_metric;
384 mpath->exp_time = time_after(mpath->exp_time, exp_time)
385 ? mpath->exp_time : exp_time;
386 mesh_path_activate(mpath);
387 spin_unlock_bh(&mpath->state_lock);
388 mesh_path_tx_pending(mpath);
390 spin_unlock_bh(&mpath->state_lock);
395 return process ? new_metric : 0;
398 static void hwmp_preq_frame_process(struct net_device *dev,
399 struct ieee80211_mgmt *mgmt,
400 u8 *preq_elem, u32 metric) {
401 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
402 struct ieee80211_if_sta *ifsta = &sdata->u.sta;
403 struct mesh_path *mpath;
404 u8 *dst_addr, *orig_addr;
406 u32 orig_dsn, dst_dsn, lifetime;
410 /* Update destination DSN, if present */
411 dst_addr = PREQ_IE_DST_ADDR(preq_elem);
412 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
413 dst_dsn = PREQ_IE_DST_DSN(preq_elem);
414 orig_dsn = PREQ_IE_ORIG_DSN(preq_elem);
415 dst_flags = PREQ_IE_DST_F(preq_elem);
417 if (memcmp(dst_addr, dev->dev_addr, ETH_ALEN) == 0) {
421 if (time_after(jiffies, ifsta->last_dsn_update +
422 net_traversal_jiffies(sdata)) ||
423 time_before(jiffies, ifsta->last_dsn_update)) {
424 dst_dsn = ++ifsta->dsn;
425 ifsta->last_dsn_update = jiffies;
429 mpath = mesh_path_lookup(dst_addr, dev);
431 if ((!(mpath->flags & MESH_PATH_DSN_VALID)) ||
432 DSN_LT(mpath->dsn, dst_dsn)) {
433 mpath->dsn = dst_dsn;
434 mpath->flags &= MESH_PATH_DSN_VALID;
435 } else if ((!(dst_flags & MP_F_DO)) &&
436 (mpath->flags & MESH_PATH_ACTIVE)) {
438 metric = mpath->metric;
439 dst_dsn = mpath->dsn;
440 if (dst_flags & MP_F_RF)
441 dst_flags |= MP_F_DO;
450 lifetime = PREQ_IE_LIFETIME(preq_elem);
451 ttl = ifsta->mshcfg.dot11MeshTTL;
453 mesh_path_sel_frame_tx(MPATH_PREP, 0, dst_addr,
454 cpu_to_le32(dst_dsn), 0, orig_addr,
455 cpu_to_le32(orig_dsn), mgmt->sa, 0, ttl,
456 cpu_to_le32(lifetime), cpu_to_le32(metric),
459 ifsta->mshstats.dropped_frames_ttl++;
466 ttl = PREQ_IE_TTL(preq_elem);
467 lifetime = PREQ_IE_LIFETIME(preq_elem);
469 ifsta->mshstats.dropped_frames_ttl++;
473 flags = PREQ_IE_FLAGS(preq_elem);
474 preq_id = PREQ_IE_PREQ_ID(preq_elem);
475 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
476 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
477 cpu_to_le32(orig_dsn), dst_flags, dst_addr,
478 cpu_to_le32(dst_dsn), dev->broadcast,
479 hopcount, ttl, cpu_to_le32(lifetime),
480 cpu_to_le32(metric), cpu_to_le32(preq_id),
482 ifsta->mshstats.fwded_frames++;
487 static void hwmp_prep_frame_process(struct net_device *dev,
488 struct ieee80211_mgmt *mgmt,
489 u8 *prep_elem, u32 metric)
491 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
492 struct mesh_path *mpath;
493 u8 *dst_addr, *orig_addr;
494 u8 ttl, hopcount, flags;
495 u8 next_hop[ETH_ALEN];
496 u32 dst_dsn, orig_dsn, lifetime;
498 /* Note that we divert from the draft nomenclature and denominate
499 * destination to what the draft refers to as origininator. So in this
500 * function destnation refers to the final destination of the PREP,
501 * which corresponds with the originator of the PREQ which this PREP
504 dst_addr = PREP_IE_DST_ADDR(prep_elem);
505 if (memcmp(dst_addr, dev->dev_addr, ETH_ALEN) == 0)
506 /* destination, no forwarding required */
509 ttl = PREP_IE_TTL(prep_elem);
511 sdata->u.sta.mshstats.dropped_frames_ttl++;
516 mpath = mesh_path_lookup(dst_addr, dev);
518 spin_lock_bh(&mpath->state_lock);
521 if (!(mpath->flags & MESH_PATH_ACTIVE)) {
522 spin_unlock_bh(&mpath->state_lock);
525 memcpy(next_hop, mpath->next_hop->addr, ETH_ALEN);
526 spin_unlock_bh(&mpath->state_lock);
528 flags = PREP_IE_FLAGS(prep_elem);
529 lifetime = PREP_IE_LIFETIME(prep_elem);
530 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
531 orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
532 dst_dsn = PREP_IE_DST_DSN(prep_elem);
533 orig_dsn = PREP_IE_ORIG_DSN(prep_elem);
535 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr,
536 cpu_to_le32(orig_dsn), 0, dst_addr,
537 cpu_to_le32(dst_dsn), mpath->next_hop->addr, hopcount, ttl,
538 cpu_to_le32(lifetime), cpu_to_le32(metric),
541 sdata->u.sta.mshstats.fwded_frames++;
546 sdata->u.sta.mshstats.dropped_frames_no_route++;
550 static void hwmp_perr_frame_process(struct net_device *dev,
551 struct ieee80211_mgmt *mgmt, u8 *perr_elem)
553 struct mesh_path *mpath;
558 dst_addr = PERR_IE_DST_ADDR(perr_elem);
559 dst_dsn = PERR_IE_DST_DSN(perr_elem);
561 mpath = mesh_path_lookup(dst_addr, dev);
563 spin_lock_bh(&mpath->state_lock);
564 if (mpath->flags & MESH_PATH_ACTIVE &&
565 memcmp(ta, mpath->next_hop->addr, ETH_ALEN) == 0 &&
566 (!(mpath->flags & MESH_PATH_DSN_VALID) ||
567 DSN_GT(dst_dsn, mpath->dsn))) {
568 mpath->flags &= ~MESH_PATH_ACTIVE;
569 mpath->dsn = dst_dsn;
570 spin_unlock_bh(&mpath->state_lock);
571 mesh_path_error_tx(dst_addr, cpu_to_le32(dst_dsn),
572 dev->broadcast, dev);
574 spin_unlock_bh(&mpath->state_lock);
581 void mesh_rx_path_sel_frame(struct net_device *dev,
582 struct ieee80211_mgmt *mgmt,
585 struct ieee802_11_elems elems;
589 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
590 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
591 len - baselen, &elems);
593 switch (mgmt->u.action.u.mesh_action.action_code) {
595 if (!elems.preq || elems.preq_len != 37)
596 /* Right now we support just 1 destination and no AE */
598 last_hop_metric = hwmp_route_info_get(dev, mgmt, elems.preq);
599 if (!last_hop_metric)
601 hwmp_preq_frame_process(dev, mgmt, elems.preq, last_hop_metric);
604 if (!elems.prep || elems.prep_len != 31)
605 /* Right now we support no AE */
607 last_hop_metric = hwmp_route_info_get(dev, mgmt, elems.prep);
608 if (!last_hop_metric)
610 hwmp_prep_frame_process(dev, mgmt, elems.prep, last_hop_metric);
613 if (!elems.perr || elems.perr_len != 12)
614 /* Right now we support only one destination per PERR */
616 hwmp_perr_frame_process(dev, mgmt, elems.perr);
624 * mesh_queue_preq - queue a PREQ to a given destination
626 * @mpath: mesh path to discover
627 * @flags: special attributes of the PREQ to be sent
629 * Locking: the function must be called from within a rcu read lock block.
632 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
634 struct ieee80211_sub_if_data *sdata =
635 IEEE80211_DEV_TO_SUB_IF(mpath->dev);
636 struct ieee80211_if_sta *ifsta = &sdata->u.sta;
637 struct mesh_preq_queue *preq_node;
639 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_KERNEL);
641 printk(KERN_DEBUG "Mesh HWMP: could not allocate PREQ node\n");
645 spin_lock(&ifsta->mesh_preq_queue_lock);
646 if (ifsta->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
647 spin_unlock(&ifsta->mesh_preq_queue_lock);
649 if (printk_ratelimit())
650 printk(KERN_DEBUG "Mesh HWMP: PREQ node queue full\n");
654 memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
655 preq_node->flags = flags;
657 list_add_tail(&preq_node->list, &ifsta->preq_queue.list);
658 ++ifsta->preq_queue_len;
659 spin_unlock(&ifsta->mesh_preq_queue_lock);
661 if (time_after(jiffies, ifsta->last_preq + min_preq_int_jiff(sdata)))
662 queue_work(sdata->local->hw.workqueue, &ifsta->work);
664 else if (time_before(jiffies, ifsta->last_preq)) {
665 /* avoid long wait if did not send preqs for a long time
666 * and jiffies wrapped around
668 ifsta->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
669 queue_work(sdata->local->hw.workqueue, &ifsta->work);
671 mod_timer(&ifsta->mesh_path_timer, ifsta->last_preq +
672 min_preq_int_jiff(sdata));
676 * mesh_path_start_discovery - launch a path discovery from the PREQ queue
678 * @dev: local mesh interface
680 void mesh_path_start_discovery(struct net_device *dev)
682 struct ieee80211_sub_if_data *sdata =
683 IEEE80211_DEV_TO_SUB_IF(dev);
684 struct ieee80211_if_sta *ifsta = &sdata->u.sta;
685 struct mesh_preq_queue *preq_node;
686 struct mesh_path *mpath;
690 spin_lock(&ifsta->mesh_preq_queue_lock);
691 if (!ifsta->preq_queue_len ||
692 time_before(jiffies, ifsta->last_preq +
693 min_preq_int_jiff(sdata))) {
694 spin_unlock(&ifsta->mesh_preq_queue_lock);
698 preq_node = list_first_entry(&ifsta->preq_queue.list,
699 struct mesh_preq_queue, list);
700 list_del(&preq_node->list);
701 --ifsta->preq_queue_len;
702 spin_unlock(&ifsta->mesh_preq_queue_lock);
705 mpath = mesh_path_lookup(preq_node->dst, dev);
709 spin_lock_bh(&mpath->state_lock);
710 if (preq_node->flags & PREQ_Q_F_START) {
711 if (mpath->flags & MESH_PATH_RESOLVING) {
712 spin_unlock_bh(&mpath->state_lock);
715 mpath->flags &= ~MESH_PATH_RESOLVED;
716 mpath->flags |= MESH_PATH_RESOLVING;
717 mpath->discovery_retries = 0;
718 mpath->discovery_timeout = disc_timeout_jiff(sdata);
720 } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
721 mpath->flags & MESH_PATH_RESOLVED) {
722 mpath->flags &= ~MESH_PATH_RESOLVING;
723 spin_unlock_bh(&mpath->state_lock);
727 ifsta->last_preq = jiffies;
729 if (time_after(jiffies, ifsta->last_dsn_update +
730 net_traversal_jiffies(sdata)) ||
731 time_before(jiffies, ifsta->last_dsn_update)) {
733 sdata->u.sta.last_dsn_update = jiffies;
735 lifetime = default_lifetime(sdata);
736 ttl = sdata->u.sta.mshcfg.dot11MeshTTL;
738 sdata->u.sta.mshstats.dropped_frames_ttl++;
739 spin_unlock_bh(&mpath->state_lock);
743 if (preq_node->flags & PREQ_Q_F_REFRESH)
748 spin_unlock_bh(&mpath->state_lock);
749 mesh_path_sel_frame_tx(MPATH_PREQ, 0, dev->dev_addr,
750 cpu_to_le32(ifsta->dsn), dst_flags, mpath->dst,
751 cpu_to_le32(mpath->dsn), dev->broadcast, 0,
752 ttl, cpu_to_le32(lifetime), 0,
753 cpu_to_le32(ifsta->preq_id++), dev);
754 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
762 * ieee80211s_lookup_nexthop - put the appropriate next hop on a mesh frame
764 * @next_hop: output argument for next hop address
765 * @skb: frame to be sent
766 * @dev: network device the frame will be sent through
768 * Returns: 0 if the next hop was found. Nonzero otherwise. If no next hop is
769 * found, the function will start a path discovery and queue the frame so it is
770 * sent when the path is resolved. This means the caller must not free the skb
773 int mesh_nexthop_lookup(u8 *next_hop, struct sk_buff *skb,
774 struct net_device *dev)
776 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
777 struct sk_buff *skb_to_free = NULL;
778 struct mesh_path *mpath;
782 mpath = mesh_path_lookup(skb->data, dev);
785 mesh_path_add(skb->data, dev);
786 mpath = mesh_path_lookup(skb->data, dev);
789 sdata->u.sta.mshstats.dropped_frames_no_route++;
795 if (mpath->flags & MESH_PATH_ACTIVE) {
796 if (time_after(jiffies, mpath->exp_time -
797 msecs_to_jiffies(sdata->u.sta.mshcfg.path_refresh_time))
798 && skb->pkt_type != PACKET_OTHERHOST
799 && !(mpath->flags & MESH_PATH_RESOLVING)
800 && !(mpath->flags & MESH_PATH_FIXED)) {
801 mesh_queue_preq(mpath,
802 PREQ_Q_F_START | PREQ_Q_F_REFRESH);
804 memcpy(next_hop, mpath->next_hop->addr,
807 if (!(mpath->flags & MESH_PATH_RESOLVING)) {
808 /* Start discovery only if it is not running yet */
809 mesh_queue_preq(mpath, PREQ_Q_F_START);
812 if (skb_queue_len(&mpath->frame_queue) >=
813 MESH_FRAME_QUEUE_LEN) {
814 skb_to_free = mpath->frame_queue.next;
815 skb_unlink(skb_to_free, &mpath->frame_queue);
818 skb_queue_tail(&mpath->frame_queue, skb);
820 mesh_path_discard_frame(skb_to_free, dev);
829 void mesh_path_timer(unsigned long data)
831 struct ieee80211_sub_if_data *sdata;
832 struct mesh_path *mpath;
835 mpath = (struct mesh_path *) data;
836 mpath = rcu_dereference(mpath);
839 spin_lock_bh(&mpath->state_lock);
840 sdata = IEEE80211_DEV_TO_SUB_IF(mpath->dev);
841 if (mpath->flags & MESH_PATH_RESOLVED ||
842 (!(mpath->flags & MESH_PATH_RESOLVING)))
843 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
844 else if (mpath->discovery_retries < max_preq_retries(sdata)) {
845 ++mpath->discovery_retries;
846 mpath->discovery_timeout *= 2;
847 mesh_queue_preq(mpath, 0);
850 mpath->exp_time = jiffies;
851 mesh_path_flush_pending(mpath);
854 spin_unlock_bh(&mpath->state_lock);