[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/net/mac80211/mesh_hwmp.c b/src/kernel/linux/v4.14/net/mac80211/mesh_hwmp.c
new file mode 100644
index 0000000..fe65701
--- /dev/null
+++ b/src/kernel/linux/v4.14/net/mac80211/mesh_hwmp.c
@@ -0,0 +1,1279 @@
+/*
+ * Copyright (c) 2008, 2009 open80211s Ltd.
+ * Author: Luis Carlos Cobo <luisca@cozybit.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/slab.h>
+#include <linux/etherdevice.h>
+#include <asm/unaligned.h>
+#include "wme.h"
+#include "mesh.h"
+
+#define TEST_FRAME_LEN 8192
+#define MAX_METRIC 0xffffffff
+#define ARITH_SHIFT 8
+#define LINK_FAIL_THRESH 95
+
+#define MAX_PREQ_QUEUE_LEN 64
+
+static void mesh_queue_preq(struct mesh_path *, u8);
+
+static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae)
+{
+ if (ae)
+ offset += 6;
+ return get_unaligned_le32(preq_elem + offset);
+}
+
+static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae)
+{
+ if (ae)
+ offset += 6;
+ return get_unaligned_le16(preq_elem + offset);
+}
+
+/* HWMP IE processing macros */
+#define AE_F (1<<6)
+#define AE_F_SET(x) (*x & AE_F)
+#define PREQ_IE_FLAGS(x) (*(x))
+#define PREQ_IE_HOPCOUNT(x) (*(x + 1))
+#define PREQ_IE_TTL(x) (*(x + 2))
+#define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
+#define PREQ_IE_ORIG_ADDR(x) (x + 7)
+#define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0)
+#define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x))
+#define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x))
+#define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
+#define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
+#define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x))
+
+
+#define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
+#define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
+#define PREP_IE_TTL(x) PREQ_IE_TTL(x)
+#define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
+#define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x))
+#define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x))
+#define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x))
+#define PREP_IE_TARGET_ADDR(x) (x + 3)
+#define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
+
+#define PERR_IE_TTL(x) (*(x))
+#define PERR_IE_TARGET_FLAGS(x) (*(x + 2))
+#define PERR_IE_TARGET_ADDR(x) (x + 3)
+#define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
+#define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0)
+
+#define MSEC_TO_TU(x) (x*1000/1024)
+#define SN_GT(x, y) ((s32)(y - x) < 0)
+#define SN_LT(x, y) ((s32)(x - y) < 0)
+#define MAX_SANE_SN_DELTA 32
+
+static inline u32 SN_DELTA(u32 x, u32 y)
+{
+ return x >= y ? x - y : y - x;
+}
+
+#define net_traversal_jiffies(s) \
+ msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
+#define default_lifetime(s) \
+ MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout)
+#define min_preq_int_jiff(s) \
+ (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval))
+#define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries)
+#define disc_timeout_jiff(s) \
+ msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout)
+#define root_path_confirmation_jiffies(s) \
+ msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval)
+
+enum mpath_frame_type {
+ MPATH_PREQ = 0,
+ MPATH_PREP,
+ MPATH_PERR,
+ MPATH_RANN
+};
+
+static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+
+static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
+ const u8 *orig_addr, u32 orig_sn,
+ u8 target_flags, const u8 *target,
+ u32 target_sn, const u8 *da,
+ u8 hop_count, u8 ttl,
+ u32 lifetime, u32 metric, u32 preq_id,
+ struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct sk_buff *skb;
+ struct ieee80211_mgmt *mgmt;
+ u8 *pos, ie_len;
+ int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
+ sizeof(mgmt->u.action.u.mesh_action);
+
+ skb = dev_alloc_skb(local->tx_headroom +
+ hdr_len +
+ 2 + 37); /* max HWMP IE */
+ if (!skb)
+ return -1;
+ skb_reserve(skb, local->tx_headroom);
+ mgmt = skb_put_zero(skb, hdr_len);
+ mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+ IEEE80211_STYPE_ACTION);
+
+ memcpy(mgmt->da, da, ETH_ALEN);
+ memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
+ /* BSSID == SA */
+ memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
+ mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
+ mgmt->u.action.u.mesh_action.action_code =
+ WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
+
+ switch (action) {
+ case MPATH_PREQ:
+ mhwmp_dbg(sdata, "sending PREQ to %pM\n", target);
+ ie_len = 37;
+ pos = skb_put(skb, 2 + ie_len);
+ *pos++ = WLAN_EID_PREQ;
+ break;
+ case MPATH_PREP:
+ mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr);
+ ie_len = 31;
+ pos = skb_put(skb, 2 + ie_len);
+ *pos++ = WLAN_EID_PREP;
+ break;
+ case MPATH_RANN:
+ mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr);
+ ie_len = sizeof(struct ieee80211_rann_ie);
+ pos = skb_put(skb, 2 + ie_len);
+ *pos++ = WLAN_EID_RANN;
+ break;
+ default:
+ kfree_skb(skb);
+ return -ENOTSUPP;
+ }
+ *pos++ = ie_len;
+ *pos++ = flags;
+ *pos++ = hop_count;
+ *pos++ = ttl;
+ if (action == MPATH_PREP) {
+ memcpy(pos, target, ETH_ALEN);
+ pos += ETH_ALEN;
+ put_unaligned_le32(target_sn, pos);
+ pos += 4;
+ } else {
+ if (action == MPATH_PREQ) {
+ put_unaligned_le32(preq_id, pos);
+ pos += 4;
+ }
+ memcpy(pos, orig_addr, ETH_ALEN);
+ pos += ETH_ALEN;
+ put_unaligned_le32(orig_sn, pos);
+ pos += 4;
+ }
+ put_unaligned_le32(lifetime, pos); /* interval for RANN */
+ pos += 4;
+ put_unaligned_le32(metric, pos);
+ pos += 4;
+ if (action == MPATH_PREQ) {
+ *pos++ = 1; /* destination count */
+ *pos++ = target_flags;
+ memcpy(pos, target, ETH_ALEN);
+ pos += ETH_ALEN;
+ put_unaligned_le32(target_sn, pos);
+ pos += 4;
+ } else if (action == MPATH_PREP) {
+ memcpy(pos, orig_addr, ETH_ALEN);
+ pos += ETH_ALEN;
+ put_unaligned_le32(orig_sn, pos);
+ pos += 4;
+ }
+
+ ieee80211_tx_skb(sdata, skb);
+ return 0;
+}
+
+
+/* Headroom is not adjusted. Caller should ensure that skb has sufficient
+ * headroom in case the frame is encrypted. */
+static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
+ struct sk_buff *skb)
+{
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+
+ skb_reset_mac_header(skb);
+ skb_reset_network_header(skb);
+ skb_reset_transport_header(skb);
+
+ /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
+ skb_set_queue_mapping(skb, IEEE80211_AC_VO);
+ skb->priority = 7;
+
+ info->control.vif = &sdata->vif;
+ info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
+ ieee80211_set_qos_hdr(sdata, skb);
+ ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
+}
+
+/**
+ * mesh_path_error_tx - Sends a PERR mesh management frame
+ *
+ * @ttl: allowed remaining hops
+ * @target: broken destination
+ * @target_sn: SN of the broken destination
+ * @target_rcode: reason code for this PERR
+ * @ra: node this frame is addressed to
+ * @sdata: local mesh subif
+ *
+ * Note: This function may be called with driver locks taken that the driver
+ * also acquires in the TX path. To avoid a deadlock we don't transmit the
+ * frame directly but add it to the pending queue instead.
+ */
+int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
+ u8 ttl, const u8 *target, u32 target_sn,
+ u16 target_rcode, const u8 *ra)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct sk_buff *skb;
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct ieee80211_mgmt *mgmt;
+ u8 *pos, ie_len;
+ int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
+ sizeof(mgmt->u.action.u.mesh_action);
+
+ if (time_before(jiffies, ifmsh->next_perr))
+ return -EAGAIN;
+
+ skb = dev_alloc_skb(local->tx_headroom +
+ sdata->encrypt_headroom +
+ IEEE80211_ENCRYPT_TAILROOM +
+ hdr_len +
+ 2 + 15 /* PERR IE */);
+ if (!skb)
+ return -1;
+ skb_reserve(skb, local->tx_headroom + sdata->encrypt_headroom);
+ mgmt = skb_put_zero(skb, hdr_len);
+ mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+ IEEE80211_STYPE_ACTION);
+
+ memcpy(mgmt->da, ra, ETH_ALEN);
+ memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
+ /* BSSID == SA */
+ memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
+ mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
+ mgmt->u.action.u.mesh_action.action_code =
+ WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
+ ie_len = 15;
+ pos = skb_put(skb, 2 + ie_len);
+ *pos++ = WLAN_EID_PERR;
+ *pos++ = ie_len;
+ /* ttl */
+ *pos++ = ttl;
+ /* number of destinations */
+ *pos++ = 1;
+ /* Flags field has AE bit only as defined in
+ * sec 8.4.2.117 IEEE802.11-2012
+ */
+ *pos = 0;
+ pos++;
+ memcpy(pos, target, ETH_ALEN);
+ pos += ETH_ALEN;
+ put_unaligned_le32(target_sn, pos);
+ pos += 4;
+ put_unaligned_le16(target_rcode, pos);
+
+ /* see note in function header */
+ prepare_frame_for_deferred_tx(sdata, skb);
+ ifmsh->next_perr = TU_TO_EXP_TIME(
+ ifmsh->mshcfg.dot11MeshHWMPperrMinInterval);
+ ieee80211_add_pending_skb(local, skb);
+ return 0;
+}
+
+void ieee80211s_update_metric(struct ieee80211_local *local,
+ struct sta_info *sta,
+ struct ieee80211_tx_status *st)
+{
+ struct ieee80211_tx_info *txinfo = st->info;
+ int failed;
+
+ failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
+
+ /* moving average, scaled to 100.
+ * feed failure as 100 and success as 0
+ */
+ ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, failed * 100);
+ if (ewma_mesh_fail_avg_read(&sta->mesh->fail_avg) >
+ LINK_FAIL_THRESH)
+ mesh_plink_broken(sta);
+}
+
+static u32 airtime_link_metric_get(struct ieee80211_local *local,
+ struct sta_info *sta)
+{
+ struct rate_info rinfo;
+ /* This should be adjusted for each device */
+ int device_constant = 1 << ARITH_SHIFT;
+ int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
+ int s_unit = 1 << ARITH_SHIFT;
+ int rate, err;
+ u32 tx_time, estimated_retx;
+ u64 result;
+ unsigned long fail_avg =
+ ewma_mesh_fail_avg_read(&sta->mesh->fail_avg);
+
+ if (sta->mesh->plink_state != NL80211_PLINK_ESTAB)
+ return MAX_METRIC;
+
+ /* Try to get rate based on HW/SW RC algorithm.
+ * Rate is returned in units of Kbps, correct this
+ * to comply with airtime calculation units
+ * Round up in case we get rate < 100Kbps
+ */
+ rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100);
+
+ if (rate) {
+ err = 0;
+ } else {
+ if (fail_avg > LINK_FAIL_THRESH)
+ return MAX_METRIC;
+
+ sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo);
+ rate = cfg80211_calculate_bitrate(&rinfo);
+ if (WARN_ON(!rate))
+ return MAX_METRIC;
+
+ err = (fail_avg << ARITH_SHIFT) / 100;
+ }
+
+ /* bitrate is in units of 100 Kbps, while we need rate in units of
+ * 1Mbps. This will be corrected on tx_time computation.
+ */
+ tx_time = (device_constant + 10 * test_frame_len / rate);
+ estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
+ result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT);
+ return (u32)result;
+}
+
+/**
+ * hwmp_route_info_get - Update routing info to originator and transmitter
+ *
+ * @sdata: local mesh subif
+ * @mgmt: mesh management frame
+ * @hwmp_ie: hwmp information element (PREP or PREQ)
+ * @action: type of hwmp ie
+ *
+ * This function updates the path routing information to the originator and the
+ * transmitter of a HWMP PREQ or PREP frame.
+ *
+ * Returns: metric to frame originator or 0 if the frame should not be further
+ * processed
+ *
+ * Notes: this function is the only place (besides user-provided info) where
+ * path routing information is updated.
+ */
+static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt,
+ const u8 *hwmp_ie, enum mpath_frame_type action)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct mesh_path *mpath;
+ struct sta_info *sta;
+ bool fresh_info;
+ const u8 *orig_addr, *ta;
+ u32 orig_sn, orig_metric;
+ unsigned long orig_lifetime, exp_time;
+ u32 last_hop_metric, new_metric;
+ bool process = true;
+
+ rcu_read_lock();
+ sta = sta_info_get(sdata, mgmt->sa);
+ if (!sta) {
+ rcu_read_unlock();
+ return 0;
+ }
+
+ last_hop_metric = airtime_link_metric_get(local, sta);
+ /* Update and check originator routing info */
+ fresh_info = true;
+
+ switch (action) {
+ case MPATH_PREQ:
+ orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
+ orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
+ orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
+ orig_metric = PREQ_IE_METRIC(hwmp_ie);
+ break;
+ case MPATH_PREP:
+ /* Originator here refers to the MP that was the target in the
+ * Path Request. We divert from the nomenclature in the draft
+ * so that we can easily use a single function to gather path
+ * information from both PREQ and PREP frames.
+ */
+ orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
+ orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
+ orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
+ orig_metric = PREP_IE_METRIC(hwmp_ie);
+ break;
+ default:
+ rcu_read_unlock();
+ return 0;
+ }
+ new_metric = orig_metric + last_hop_metric;
+ if (new_metric < orig_metric)
+ new_metric = MAX_METRIC;
+ exp_time = TU_TO_EXP_TIME(orig_lifetime);
+
+ if (ether_addr_equal(orig_addr, sdata->vif.addr)) {
+ /* This MP is the originator, we are not interested in this
+ * frame, except for updating transmitter's path info.
+ */
+ process = false;
+ fresh_info = false;
+ } else {
+ mpath = mesh_path_lookup(sdata, orig_addr);
+ if (mpath) {
+ spin_lock_bh(&mpath->state_lock);
+ if (mpath->flags & MESH_PATH_FIXED)
+ fresh_info = false;
+ else if ((mpath->flags & MESH_PATH_ACTIVE) &&
+ (mpath->flags & MESH_PATH_SN_VALID)) {
+ if (SN_GT(mpath->sn, orig_sn) ||
+ (mpath->sn == orig_sn &&
+ new_metric >= mpath->metric)) {
+ process = false;
+ fresh_info = false;
+ }
+ } else if (!(mpath->flags & MESH_PATH_ACTIVE)) {
+ bool have_sn, newer_sn, bounced;
+
+ have_sn = mpath->flags & MESH_PATH_SN_VALID;
+ newer_sn = have_sn && SN_GT(orig_sn, mpath->sn);
+ bounced = have_sn &&
+ (SN_DELTA(orig_sn, mpath->sn) >
+ MAX_SANE_SN_DELTA);
+
+ if (!have_sn || newer_sn) {
+ /* if SN is newer than what we had
+ * then we can take it */;
+ } else if (bounced) {
+ /* if SN is way different than what
+ * we had then assume the other side
+ * rebooted or restarted */;
+ } else {
+ process = false;
+ fresh_info = false;
+ }
+ }
+ } else {
+ mpath = mesh_path_add(sdata, orig_addr);
+ if (IS_ERR(mpath)) {
+ rcu_read_unlock();
+ return 0;
+ }
+ spin_lock_bh(&mpath->state_lock);
+ }
+
+ if (fresh_info) {
+ mesh_path_assign_nexthop(mpath, sta);
+ mpath->flags |= MESH_PATH_SN_VALID;
+ mpath->metric = new_metric;
+ mpath->sn = orig_sn;
+ mpath->exp_time = time_after(mpath->exp_time, exp_time)
+ ? mpath->exp_time : exp_time;
+ mesh_path_activate(mpath);
+ spin_unlock_bh(&mpath->state_lock);
+ ewma_mesh_fail_avg_init(&sta->mesh->fail_avg);
+ /* init it at a low value - 0 start is tricky */
+ ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1);
+ mesh_path_tx_pending(mpath);
+ /* draft says preq_id should be saved to, but there does
+ * not seem to be any use for it, skipping by now
+ */
+ } else
+ spin_unlock_bh(&mpath->state_lock);
+ }
+
+ /* Update and check transmitter routing info */
+ ta = mgmt->sa;
+ if (ether_addr_equal(orig_addr, ta))
+ fresh_info = false;
+ else {
+ fresh_info = true;
+
+ mpath = mesh_path_lookup(sdata, ta);
+ if (mpath) {
+ spin_lock_bh(&mpath->state_lock);
+ if ((mpath->flags & MESH_PATH_FIXED) ||
+ ((mpath->flags & MESH_PATH_ACTIVE) &&
+ (last_hop_metric > mpath->metric)))
+ fresh_info = false;
+ } else {
+ mpath = mesh_path_add(sdata, ta);
+ if (IS_ERR(mpath)) {
+ rcu_read_unlock();
+ return 0;
+ }
+ spin_lock_bh(&mpath->state_lock);
+ }
+
+ if (fresh_info) {
+ mesh_path_assign_nexthop(mpath, sta);
+ mpath->metric = last_hop_metric;
+ mpath->exp_time = time_after(mpath->exp_time, exp_time)
+ ? mpath->exp_time : exp_time;
+ mesh_path_activate(mpath);
+ spin_unlock_bh(&mpath->state_lock);
+ ewma_mesh_fail_avg_init(&sta->mesh->fail_avg);
+ /* init it at a low value - 0 start is tricky */
+ ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1);
+ mesh_path_tx_pending(mpath);
+ } else
+ spin_unlock_bh(&mpath->state_lock);
+ }
+
+ rcu_read_unlock();
+
+ return process ? new_metric : 0;
+}
+
+static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt,
+ const u8 *preq_elem, u32 orig_metric)
+{
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct mesh_path *mpath = NULL;
+ const u8 *target_addr, *orig_addr;
+ const u8 *da;
+ u8 target_flags, ttl, flags;
+ u32 orig_sn, target_sn, lifetime, target_metric = 0;
+ bool reply = false;
+ bool forward = true;
+ bool root_is_gate;
+
+ /* Update target SN, if present */
+ target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
+ orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
+ target_sn = PREQ_IE_TARGET_SN(preq_elem);
+ orig_sn = PREQ_IE_ORIG_SN(preq_elem);
+ target_flags = PREQ_IE_TARGET_F(preq_elem);
+ /* Proactive PREQ gate announcements */
+ flags = PREQ_IE_FLAGS(preq_elem);
+ root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
+
+ mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr);
+
+ if (ether_addr_equal(target_addr, sdata->vif.addr)) {
+ mhwmp_dbg(sdata, "PREQ is for us\n");
+ forward = false;
+ reply = true;
+ target_metric = 0;
+
+ if (SN_GT(target_sn, ifmsh->sn))
+ ifmsh->sn = target_sn;
+
+ if (time_after(jiffies, ifmsh->last_sn_update +
+ net_traversal_jiffies(sdata)) ||
+ time_before(jiffies, ifmsh->last_sn_update)) {
+ ++ifmsh->sn;
+ ifmsh->last_sn_update = jiffies;
+ }
+ target_sn = ifmsh->sn;
+ } else if (is_broadcast_ether_addr(target_addr) &&
+ (target_flags & IEEE80211_PREQ_TO_FLAG)) {
+ rcu_read_lock();
+ mpath = mesh_path_lookup(sdata, orig_addr);
+ if (mpath) {
+ if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
+ reply = true;
+ target_addr = sdata->vif.addr;
+ target_sn = ++ifmsh->sn;
+ target_metric = 0;
+ ifmsh->last_sn_update = jiffies;
+ }
+ if (root_is_gate)
+ mesh_path_add_gate(mpath);
+ }
+ rcu_read_unlock();
+ } else {
+ rcu_read_lock();
+ mpath = mesh_path_lookup(sdata, target_addr);
+ if (mpath) {
+ if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
+ SN_LT(mpath->sn, target_sn)) {
+ mpath->sn = target_sn;
+ mpath->flags |= MESH_PATH_SN_VALID;
+ } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) &&
+ (mpath->flags & MESH_PATH_ACTIVE)) {
+ reply = true;
+ target_metric = mpath->metric;
+ target_sn = mpath->sn;
+ /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/
+ target_flags |= IEEE80211_PREQ_TO_FLAG;
+ }
+ }
+ rcu_read_unlock();
+ }
+
+ if (reply) {
+ lifetime = PREQ_IE_LIFETIME(preq_elem);
+ ttl = ifmsh->mshcfg.element_ttl;
+ if (ttl != 0) {
+ mhwmp_dbg(sdata, "replying to the PREQ\n");
+ mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
+ orig_sn, 0, target_addr,
+ target_sn, mgmt->sa, 0, ttl,
+ lifetime, target_metric, 0,
+ sdata);
+ } else {
+ ifmsh->mshstats.dropped_frames_ttl++;
+ }
+ }
+
+ if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
+ u32 preq_id;
+ u8 hopcount;
+
+ ttl = PREQ_IE_TTL(preq_elem);
+ lifetime = PREQ_IE_LIFETIME(preq_elem);
+ if (ttl <= 1) {
+ ifmsh->mshstats.dropped_frames_ttl++;
+ return;
+ }
+ mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr);
+ --ttl;
+ preq_id = PREQ_IE_PREQ_ID(preq_elem);
+ hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
+ da = (mpath && mpath->is_root) ?
+ mpath->rann_snd_addr : broadcast_addr;
+
+ if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) {
+ target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
+ target_sn = PREQ_IE_TARGET_SN(preq_elem);
+ }
+
+ mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
+ orig_sn, target_flags, target_addr,
+ target_sn, da, hopcount, ttl, lifetime,
+ orig_metric, preq_id, sdata);
+ if (!is_multicast_ether_addr(da))
+ ifmsh->mshstats.fwded_unicast++;
+ else
+ ifmsh->mshstats.fwded_mcast++;
+ ifmsh->mshstats.fwded_frames++;
+ }
+}
+
+
+static inline struct sta_info *
+next_hop_deref_protected(struct mesh_path *mpath)
+{
+ return rcu_dereference_protected(mpath->next_hop,
+ lockdep_is_held(&mpath->state_lock));
+}
+
+
+static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt,
+ const u8 *prep_elem, u32 metric)
+{
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct mesh_path *mpath;
+ const u8 *target_addr, *orig_addr;
+ u8 ttl, hopcount, flags;
+ u8 next_hop[ETH_ALEN];
+ u32 target_sn, orig_sn, lifetime;
+
+ mhwmp_dbg(sdata, "received PREP from %pM\n",
+ PREP_IE_TARGET_ADDR(prep_elem));
+
+ orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
+ if (ether_addr_equal(orig_addr, sdata->vif.addr))
+ /* destination, no forwarding required */
+ return;
+
+ if (!ifmsh->mshcfg.dot11MeshForwarding)
+ return;
+
+ ttl = PREP_IE_TTL(prep_elem);
+ if (ttl <= 1) {
+ sdata->u.mesh.mshstats.dropped_frames_ttl++;
+ return;
+ }
+
+ rcu_read_lock();
+ mpath = mesh_path_lookup(sdata, orig_addr);
+ if (mpath)
+ spin_lock_bh(&mpath->state_lock);
+ else
+ goto fail;
+ if (!(mpath->flags & MESH_PATH_ACTIVE)) {
+ spin_unlock_bh(&mpath->state_lock);
+ goto fail;
+ }
+ memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
+ spin_unlock_bh(&mpath->state_lock);
+ --ttl;
+ flags = PREP_IE_FLAGS(prep_elem);
+ lifetime = PREP_IE_LIFETIME(prep_elem);
+ hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
+ target_addr = PREP_IE_TARGET_ADDR(prep_elem);
+ target_sn = PREP_IE_TARGET_SN(prep_elem);
+ orig_sn = PREP_IE_ORIG_SN(prep_elem);
+
+ mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0,
+ target_addr, target_sn, next_hop, hopcount,
+ ttl, lifetime, metric, 0, sdata);
+ rcu_read_unlock();
+
+ sdata->u.mesh.mshstats.fwded_unicast++;
+ sdata->u.mesh.mshstats.fwded_frames++;
+ return;
+
+fail:
+ rcu_read_unlock();
+ sdata->u.mesh.mshstats.dropped_frames_no_route++;
+}
+
+static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt,
+ const u8 *perr_elem)
+{
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct mesh_path *mpath;
+ u8 ttl;
+ const u8 *ta, *target_addr;
+ u32 target_sn;
+ u16 target_rcode;
+
+ ta = mgmt->sa;
+ ttl = PERR_IE_TTL(perr_elem);
+ if (ttl <= 1) {
+ ifmsh->mshstats.dropped_frames_ttl++;
+ return;
+ }
+ ttl--;
+ target_addr = PERR_IE_TARGET_ADDR(perr_elem);
+ target_sn = PERR_IE_TARGET_SN(perr_elem);
+ target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
+
+ rcu_read_lock();
+ mpath = mesh_path_lookup(sdata, target_addr);
+ if (mpath) {
+ struct sta_info *sta;
+
+ spin_lock_bh(&mpath->state_lock);
+ sta = next_hop_deref_protected(mpath);
+ if (mpath->flags & MESH_PATH_ACTIVE &&
+ ether_addr_equal(ta, sta->sta.addr) &&
+ !(mpath->flags & MESH_PATH_FIXED) &&
+ (!(mpath->flags & MESH_PATH_SN_VALID) ||
+ SN_GT(target_sn, mpath->sn) || target_sn == 0)) {
+ mpath->flags &= ~MESH_PATH_ACTIVE;
+ if (target_sn != 0)
+ mpath->sn = target_sn;
+ else
+ mpath->sn += 1;
+ spin_unlock_bh(&mpath->state_lock);
+ if (!ifmsh->mshcfg.dot11MeshForwarding)
+ goto endperr;
+ mesh_path_error_tx(sdata, ttl, target_addr,
+ target_sn, target_rcode,
+ broadcast_addr);
+ } else
+ spin_unlock_bh(&mpath->state_lock);
+ }
+endperr:
+ rcu_read_unlock();
+}
+
+static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt,
+ const struct ieee80211_rann_ie *rann)
+{
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct ieee80211_local *local = sdata->local;
+ struct sta_info *sta;
+ struct mesh_path *mpath;
+ u8 ttl, flags, hopcount;
+ const u8 *orig_addr;
+ u32 orig_sn, new_metric, orig_metric, last_hop_metric, interval;
+ bool root_is_gate;
+
+ ttl = rann->rann_ttl;
+ flags = rann->rann_flags;
+ root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
+ orig_addr = rann->rann_addr;
+ orig_sn = le32_to_cpu(rann->rann_seq);
+ interval = le32_to_cpu(rann->rann_interval);
+ hopcount = rann->rann_hopcount;
+ hopcount++;
+ orig_metric = le32_to_cpu(rann->rann_metric);
+
+ /* Ignore our own RANNs */
+ if (ether_addr_equal(orig_addr, sdata->vif.addr))
+ return;
+
+ mhwmp_dbg(sdata,
+ "received RANN from %pM via neighbour %pM (is_gate=%d)\n",
+ orig_addr, mgmt->sa, root_is_gate);
+
+ rcu_read_lock();
+ sta = sta_info_get(sdata, mgmt->sa);
+ if (!sta) {
+ rcu_read_unlock();
+ return;
+ }
+
+ last_hop_metric = airtime_link_metric_get(local, sta);
+ new_metric = orig_metric + last_hop_metric;
+ if (new_metric < orig_metric)
+ new_metric = MAX_METRIC;
+
+ mpath = mesh_path_lookup(sdata, orig_addr);
+ if (!mpath) {
+ mpath = mesh_path_add(sdata, orig_addr);
+ if (IS_ERR(mpath)) {
+ rcu_read_unlock();
+ sdata->u.mesh.mshstats.dropped_frames_no_route++;
+ return;
+ }
+ }
+
+ if (!(SN_LT(mpath->sn, orig_sn)) &&
+ !(mpath->sn == orig_sn && new_metric < mpath->rann_metric)) {
+ rcu_read_unlock();
+ return;
+ }
+
+ if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
+ (time_after(jiffies, mpath->last_preq_to_root +
+ root_path_confirmation_jiffies(sdata)) ||
+ time_before(jiffies, mpath->last_preq_to_root))) &&
+ !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) {
+ mhwmp_dbg(sdata,
+ "time to refresh root mpath %pM\n",
+ orig_addr);
+ mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
+ mpath->last_preq_to_root = jiffies;
+ }
+
+ mpath->sn = orig_sn;
+ mpath->rann_metric = new_metric;
+ mpath->is_root = true;
+ /* Recording RANNs sender address to send individually
+ * addressed PREQs destined for root mesh STA */
+ memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
+
+ if (root_is_gate)
+ mesh_path_add_gate(mpath);
+
+ if (ttl <= 1) {
+ ifmsh->mshstats.dropped_frames_ttl++;
+ rcu_read_unlock();
+ return;
+ }
+ ttl--;
+
+ if (ifmsh->mshcfg.dot11MeshForwarding) {
+ mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
+ orig_sn, 0, NULL, 0, broadcast_addr,
+ hopcount, ttl, interval,
+ new_metric, 0, sdata);
+ }
+
+ rcu_read_unlock();
+}
+
+
+void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt, size_t len)
+{
+ struct ieee802_11_elems elems;
+ size_t baselen;
+ u32 path_metric;
+ struct sta_info *sta;
+
+ /* need action_code */
+ if (len < IEEE80211_MIN_ACTION_SIZE + 1)
+ return;
+
+ rcu_read_lock();
+ sta = sta_info_get(sdata, mgmt->sa);
+ if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
+ rcu_read_unlock();
+ return;
+ }
+ rcu_read_unlock();
+
+ baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
+ ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
+ len - baselen, false, &elems);
+
+ if (elems.preq) {
+ if (elems.preq_len != 37)
+ /* Right now we support just 1 destination and no AE */
+ return;
+ path_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
+ MPATH_PREQ);
+ if (path_metric)
+ hwmp_preq_frame_process(sdata, mgmt, elems.preq,
+ path_metric);
+ }
+ if (elems.prep) {
+ if (elems.prep_len != 31)
+ /* Right now we support no AE */
+ return;
+ path_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
+ MPATH_PREP);
+ if (path_metric)
+ hwmp_prep_frame_process(sdata, mgmt, elems.prep,
+ path_metric);
+ }
+ if (elems.perr) {
+ if (elems.perr_len != 15)
+ /* Right now we support only one destination per PERR */
+ return;
+ hwmp_perr_frame_process(sdata, mgmt, elems.perr);
+ }
+ if (elems.rann)
+ hwmp_rann_frame_process(sdata, mgmt, elems.rann);
+}
+
+/**
+ * mesh_queue_preq - queue a PREQ to a given destination
+ *
+ * @mpath: mesh path to discover
+ * @flags: special attributes of the PREQ to be sent
+ *
+ * Locking: the function must be called from within a rcu read lock block.
+ *
+ */
+static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
+{
+ struct ieee80211_sub_if_data *sdata = mpath->sdata;
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct mesh_preq_queue *preq_node;
+
+ preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
+ if (!preq_node) {
+ mhwmp_dbg(sdata, "could not allocate PREQ node\n");
+ return;
+ }
+
+ spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
+ if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
+ spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
+ kfree(preq_node);
+ if (printk_ratelimit())
+ mhwmp_dbg(sdata, "PREQ node queue full\n");
+ return;
+ }
+
+ spin_lock(&mpath->state_lock);
+ if (mpath->flags & MESH_PATH_REQ_QUEUED) {
+ spin_unlock(&mpath->state_lock);
+ spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
+ kfree(preq_node);
+ return;
+ }
+
+ memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
+ preq_node->flags = flags;
+
+ mpath->flags |= MESH_PATH_REQ_QUEUED;
+ spin_unlock(&mpath->state_lock);
+
+ list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
+ ++ifmsh->preq_queue_len;
+ spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
+
+ if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
+ ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+
+ else if (time_before(jiffies, ifmsh->last_preq)) {
+ /* avoid long wait if did not send preqs for a long time
+ * and jiffies wrapped around
+ */
+ ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
+ ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+ } else
+ mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
+ min_preq_int_jiff(sdata));
+}
+
+/**
+ * mesh_path_start_discovery - launch a path discovery from the PREQ queue
+ *
+ * @sdata: local mesh subif
+ */
+void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct mesh_preq_queue *preq_node;
+ struct mesh_path *mpath;
+ u8 ttl, target_flags = 0;
+ const u8 *da;
+ u32 lifetime;
+
+ spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
+ if (!ifmsh->preq_queue_len ||
+ time_before(jiffies, ifmsh->last_preq +
+ min_preq_int_jiff(sdata))) {
+ spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
+ return;
+ }
+
+ preq_node = list_first_entry(&ifmsh->preq_queue.list,
+ struct mesh_preq_queue, list);
+ list_del(&preq_node->list);
+ --ifmsh->preq_queue_len;
+ spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
+
+ rcu_read_lock();
+ mpath = mesh_path_lookup(sdata, preq_node->dst);
+ if (!mpath)
+ goto enddiscovery;
+
+ spin_lock_bh(&mpath->state_lock);
+ if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) {
+ spin_unlock_bh(&mpath->state_lock);
+ goto enddiscovery;
+ }
+ mpath->flags &= ~MESH_PATH_REQ_QUEUED;
+ if (preq_node->flags & PREQ_Q_F_START) {
+ if (mpath->flags & MESH_PATH_RESOLVING) {
+ spin_unlock_bh(&mpath->state_lock);
+ goto enddiscovery;
+ } else {
+ mpath->flags &= ~MESH_PATH_RESOLVED;
+ mpath->flags |= MESH_PATH_RESOLVING;
+ mpath->discovery_retries = 0;
+ mpath->discovery_timeout = disc_timeout_jiff(sdata);
+ }
+ } else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
+ mpath->flags & MESH_PATH_RESOLVED) {
+ mpath->flags &= ~MESH_PATH_RESOLVING;
+ spin_unlock_bh(&mpath->state_lock);
+ goto enddiscovery;
+ }
+
+ ifmsh->last_preq = jiffies;
+
+ if (time_after(jiffies, ifmsh->last_sn_update +
+ net_traversal_jiffies(sdata)) ||
+ time_before(jiffies, ifmsh->last_sn_update)) {
+ ++ifmsh->sn;
+ sdata->u.mesh.last_sn_update = jiffies;
+ }
+ lifetime = default_lifetime(sdata);
+ ttl = sdata->u.mesh.mshcfg.element_ttl;
+ if (ttl == 0) {
+ sdata->u.mesh.mshstats.dropped_frames_ttl++;
+ spin_unlock_bh(&mpath->state_lock);
+ goto enddiscovery;
+ }
+
+ if (preq_node->flags & PREQ_Q_F_REFRESH)
+ target_flags |= IEEE80211_PREQ_TO_FLAG;
+ else
+ target_flags &= ~IEEE80211_PREQ_TO_FLAG;
+
+ spin_unlock_bh(&mpath->state_lock);
+ da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
+ mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn,
+ target_flags, mpath->dst, mpath->sn, da, 0,
+ ttl, lifetime, 0, ifmsh->preq_id++, sdata);
+
+ spin_lock_bh(&mpath->state_lock);
+ if (mpath->flags & MESH_PATH_DELETED) {
+ spin_unlock_bh(&mpath->state_lock);
+ goto enddiscovery;
+ }
+ mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
+ spin_unlock_bh(&mpath->state_lock);
+
+enddiscovery:
+ rcu_read_unlock();
+ kfree(preq_node);
+}
+
+/**
+ * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery
+ *
+ * @skb: 802.11 frame to be sent
+ * @sdata: network subif the frame will be sent through
+ *
+ * Lookup next hop for given skb and start path discovery if no
+ * forwarding information is found.
+ *
+ * Returns: 0 if the next hop was found and -ENOENT if the frame was queued.
+ * skb is freeed here if no mpath could be allocated.
+ */
+int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
+ struct sk_buff *skb)
+{
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ struct mesh_path *mpath;
+ struct sk_buff *skb_to_free = NULL;
+ u8 *target_addr = hdr->addr3;
+ int err = 0;
+
+ /* Nulls are only sent to peers for PS and should be pre-addressed */
+ if (ieee80211_is_qos_nullfunc(hdr->frame_control))
+ return 0;
+
+ rcu_read_lock();
+ err = mesh_nexthop_lookup(sdata, skb);
+ if (!err)
+ goto endlookup;
+
+ /* no nexthop found, start resolving */
+ mpath = mesh_path_lookup(sdata, target_addr);
+ if (!mpath) {
+ mpath = mesh_path_add(sdata, target_addr);
+ if (IS_ERR(mpath)) {
+ mesh_path_discard_frame(sdata, skb);
+ err = PTR_ERR(mpath);
+ goto endlookup;
+ }
+ }
+
+ if (!(mpath->flags & MESH_PATH_RESOLVING) &&
+ mesh_path_sel_is_hwmp(sdata))
+ mesh_queue_preq(mpath, PREQ_Q_F_START);
+
+ if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
+ skb_to_free = skb_dequeue(&mpath->frame_queue);
+
+ info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
+ ieee80211_set_qos_hdr(sdata, skb);
+ skb_queue_tail(&mpath->frame_queue, skb);
+ err = -ENOENT;
+ if (skb_to_free)
+ mesh_path_discard_frame(sdata, skb_to_free);
+
+endlookup:
+ rcu_read_unlock();
+ return err;
+}
+
+/**
+ * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling
+ * this function is considered "using" the associated mpath, so preempt a path
+ * refresh if this mpath expires soon.
+ *
+ * @skb: 802.11 frame to be sent
+ * @sdata: network subif the frame will be sent through
+ *
+ * Returns: 0 if the next hop was found. Nonzero otherwise.
+ */
+int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
+ struct sk_buff *skb)
+{
+ struct mesh_path *mpath;
+ struct sta_info *next_hop;
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+ u8 *target_addr = hdr->addr3;
+ int err = -ENOENT;
+
+ rcu_read_lock();
+ mpath = mesh_path_lookup(sdata, target_addr);
+
+ if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE))
+ goto endlookup;
+
+ if (time_after(jiffies,
+ mpath->exp_time -
+ msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
+ ether_addr_equal(sdata->vif.addr, hdr->addr4) &&
+ !(mpath->flags & MESH_PATH_RESOLVING) &&
+ !(mpath->flags & MESH_PATH_FIXED))
+ mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
+
+ next_hop = rcu_dereference(mpath->next_hop);
+ if (next_hop) {
+ memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
+ memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
+ ieee80211_mps_set_frame_flags(sdata, next_hop, hdr);
+ err = 0;
+ }
+
+endlookup:
+ rcu_read_unlock();
+ return err;
+}
+
+void mesh_path_timer(unsigned long data)
+{
+ struct mesh_path *mpath = (void *) data;
+ struct ieee80211_sub_if_data *sdata = mpath->sdata;
+ int ret;
+
+ if (sdata->local->quiescing)
+ return;
+
+ spin_lock_bh(&mpath->state_lock);
+ if (mpath->flags & MESH_PATH_RESOLVED ||
+ (!(mpath->flags & MESH_PATH_RESOLVING))) {
+ mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
+ spin_unlock_bh(&mpath->state_lock);
+ } else if (mpath->discovery_retries < max_preq_retries(sdata)) {
+ ++mpath->discovery_retries;
+ mpath->discovery_timeout *= 2;
+ mpath->flags &= ~MESH_PATH_REQ_QUEUED;
+ spin_unlock_bh(&mpath->state_lock);
+ mesh_queue_preq(mpath, 0);
+ } else {
+ mpath->flags &= ~(MESH_PATH_RESOLVING |
+ MESH_PATH_RESOLVED |
+ MESH_PATH_REQ_QUEUED);
+ mpath->exp_time = jiffies;
+ spin_unlock_bh(&mpath->state_lock);
+ if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
+ ret = mesh_path_send_to_gates(mpath);
+ if (ret)
+ mhwmp_dbg(sdata, "no gate was reachable\n");
+ } else
+ mesh_path_flush_pending(mpath);
+ }
+}
+
+void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
+ u8 flags, target_flags = 0;
+
+ flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
+ ? RANN_FLAG_IS_GATE : 0;
+
+ switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) {
+ case IEEE80211_PROACTIVE_RANN:
+ mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
+ ++ifmsh->sn, 0, NULL, 0, broadcast_addr,
+ 0, ifmsh->mshcfg.element_ttl,
+ interval, 0, 0, sdata);
+ break;
+ case IEEE80211_PROACTIVE_PREQ_WITH_PREP:
+ flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG;
+ case IEEE80211_PROACTIVE_PREQ_NO_PREP:
+ interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout;
+ target_flags |= IEEE80211_PREQ_TO_FLAG |
+ IEEE80211_PREQ_USN_FLAG;
+ mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr,
+ ++ifmsh->sn, target_flags,
+ (u8 *) broadcast_addr, 0, broadcast_addr,
+ 0, ifmsh->mshcfg.element_ttl, interval,
+ 0, ifmsh->preq_id++, sdata);
+ break;
+ default:
+ mhwmp_dbg(sdata, "Proactive mechanism not supported\n");
+ return;
+ }
+}