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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright 2002-2005, Instant802 Networks, Inc.
  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
  * Copyright 2013-2014  Intel Mobile Communications GmbH
  * Copyright (C) 2015 - 2017 Intel Deutschland GmbH
  * Copyright (C) 2018-2021 Intel Corporation
  */
 
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/etherdevice.h>
 #include <linux/netdevice.h>
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/skbuff.h>
 #include <linux/if_arp.h>
 #include <linux/timer.h>
 #include <linux/rtnetlink.h>
 
 #include <net/codel.h>
 #include <net/mac80211.h>
 #include "ieee80211_i.h"
 #include "driver-ops.h"
 #include "rate.h"
 #include "sta_info.h"
 #include "debugfs_sta.h"
 #include "mesh.h"
 #include "wme.h"
 
 /**
  * DOC: STA information lifetime rules
  *
  * STA info structures (&struct sta_info) are managed in a hash table
  * for faster lookup and a list for iteration. They are managed using
  * RCU, i.e. access to the list and hash table is protected by RCU.
  *
  * Upon allocating a STA info structure with sta_info_alloc(), the caller
  * owns that structure. It must then insert it into the hash table using
  * either sta_info_insert() or sta_info_insert_rcu(); only in the latter
  * case (which acquires an rcu read section but must not be called from
  * within one) will the pointer still be valid after the call. Note that
  * the caller may not do much with the STA info before inserting it, in
  * particular, it may not start any mesh peer link management or add
  * encryption keys.
  *
  * When the insertion fails (sta_info_insert()) returns non-zero), the
  * structure will have been freed by sta_info_insert()!
  *
  * Station entries are added by mac80211 when you establish a link with a
  * peer. This means different things for the different type of interfaces
  * we support. For a regular station this mean we add the AP sta when we
  * receive an association response from the AP. For IBSS this occurs when
  * get to know about a peer on the same IBSS. For WDS we add the sta for
  * the peer immediately upon device open. When using AP mode we add stations
  * for each respective station upon request from userspace through nl80211.
  *
  * In order to remove a STA info structure, various sta_info_destroy_*()
  * calls are available.
  *
  * There is no concept of ownership on a STA entry, each structure is
  * owned by the global hash table/list until it is removed. All users of
  * the structure need to be RCU protected so that the structure won't be
  * freed before they are done using it.
  */
 
 struct sta_link_alloc {
     struct link_sta_info info;
     struct ieee80211_link_sta sta;
     struct rcu_head rcu_head;
 };
 
 static const struct rhashtable_params sta_rht_params = {
     .nelem_hint = 3, /* start small */
     .automatic_shrinking = true,
     .head_offset = offsetof(struct sta_info, hash_node),
     .key_offset = offsetof(struct sta_info, addr),
     .key_len = ETH_ALEN,
     .max_size = CONFIG_MAC80211_STA_HASH_MAX_SIZE,
 };
 
 static const struct rhashtable_params link_sta_rht_params = {
     .nelem_hint = 3, /* start small */
     .automatic_shrinking = true,
     .head_offset = offsetof(struct link_sta_info, link_hash_node),
     .key_offset = offsetof(struct link_sta_info, addr),
     .key_len = ETH_ALEN,
     .max_size = CONFIG_MAC80211_STA_HASH_MAX_SIZE,
 };
 
 /* Caller must hold local->sta_mtx */
 static int sta_info_hash_del(struct ieee80211_local *local,
                  struct sta_info *sta)
 {
     return rhltable_remove(&local->sta_hash, &sta->hash_node,
                    sta_rht_params);
 }
 
 static int link_sta_info_hash_add(struct ieee80211_local *local,
                   struct link_sta_info *link_sta)
 {
     lockdep_assert_held(&local->sta_mtx);
     return rhltable_insert(&local->link_sta_hash,
                    &link_sta->link_hash_node,
                    link_sta_rht_params);
 }
 
 static int link_sta_info_hash_del(struct ieee80211_local *local,
                   struct link_sta_info *link_sta)
 {
     lockdep_assert_held(&local->sta_mtx);
     return rhltable_remove(&local->link_sta_hash,
                    &link_sta->link_hash_node,
                    link_sta_rht_params);
 }
 
 static void __cleanup_single_sta(struct sta_info *sta)
 {
     int ac, i;
     struct tid_ampdu_tx *tid_tx;
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct ieee80211_local *local = sdata->local;
     struct ps_data *ps;
 
     if (test_sta_flag(sta, WLAN_STA_PS_STA) ||
         test_sta_flag(sta, WLAN_STA_PS_DRIVER) ||
         test_sta_flag(sta, WLAN_STA_PS_DELIVER)) {
         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
             ps = &sdata->bss->ps;
         else if (ieee80211_vif_is_mesh(&sdata->vif))
             ps = &sdata->u.mesh.ps;
         else
             return;
 
         clear_sta_flag(sta, WLAN_STA_PS_STA);
         clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
         clear_sta_flag(sta, WLAN_STA_PS_DELIVER);
 
         atomic_dec(&ps->num_sta_ps);
     }
 
     if (sta->sta.txq[0]) {
         for (i = 0; i < ARRAY_SIZE(sta->sta.txq); i++) {
             struct txq_info *txqi;
 
             if (!sta->sta.txq[i])
                 continue;
 
             txqi = to_txq_info(sta->sta.txq[i]);
 
             ieee80211_txq_purge(local, txqi);
         }
     }
 
     for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
         local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf[ac]);
         ieee80211_purge_tx_queue(&local->hw, &sta->ps_tx_buf[ac]);
         ieee80211_purge_tx_queue(&local->hw, &sta->tx_filtered[ac]);
     }
 
     if (ieee80211_vif_is_mesh(&sdata->vif))
         mesh_sta_cleanup(sta);
 
     cancel_work_sync(&sta->drv_deliver_wk);
 
     /*
      * Destroy aggregation state here. It would be nice to wait for the
      * driver to finish aggregation stop and then clean up, but for now
      * drivers have to handle aggregation stop being requested, followed
      * directly by station destruction.
      */
     for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
         kfree(sta->ampdu_mlme.tid_start_tx[i]);
         tid_tx = rcu_dereference_raw(sta->ampdu_mlme.tid_tx[i]);
         if (!tid_tx)
             continue;
         ieee80211_purge_tx_queue(&local->hw, &tid_tx->pending);
         kfree(tid_tx);
     }
 }
 
 static void cleanup_single_sta(struct sta_info *sta)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct ieee80211_local *local = sdata->local;
 
     __cleanup_single_sta(sta);
     sta_info_free(local, sta);
 }
 
 struct rhlist_head *sta_info_hash_lookup(struct ieee80211_local *local,
                      const u8 *addr)
 {
     return rhltable_lookup(&local->sta_hash, addr, sta_rht_params);
 }
 
 /* protected by RCU */
 struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata,
                   const u8 *addr)
 {
     struct ieee80211_local *local = sdata->local;
     struct rhlist_head *tmp;
     struct sta_info *sta;
 
     rcu_read_lock();
     for_each_sta_info(local, addr, sta, tmp) {
         if (sta->sdata == sdata) {
             rcu_read_unlock();
             /* this is safe as the caller must already hold
              * another rcu read section or the mutex
              */
             return sta;
         }
     }
     rcu_read_unlock();
     return NULL;
 }
 
 /*
  * Get sta info either from the specified interface
  * or from one of its vlans
  */
 struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata,
                   const u8 *addr)
 {
     struct ieee80211_local *local = sdata->local;
     struct rhlist_head *tmp;
     struct sta_info *sta;
 
     rcu_read_lock();
     for_each_sta_info(local, addr, sta, tmp) {
         if (sta->sdata == sdata ||
             (sta->sdata->bss && sta->sdata->bss == sdata->bss)) {
             rcu_read_unlock();
             /* this is safe as the caller must already hold
              * another rcu read section or the mutex
              */
             return sta;
         }
     }
     rcu_read_unlock();
     return NULL;
 }
 
 struct rhlist_head *link_sta_info_hash_lookup(struct ieee80211_local *local,
                           const u8 *addr)
 {
     return rhltable_lookup(&local->link_sta_hash, addr,
                    link_sta_rht_params);
 }
 
 struct link_sta_info *
 link_sta_info_get_bss(struct ieee80211_sub_if_data *sdata, const u8 *addr)
 {
     struct ieee80211_local *local = sdata->local;
     struct rhlist_head *tmp;
     struct link_sta_info *link_sta;
 
     rcu_read_lock();
     for_each_link_sta_info(local, addr, link_sta, tmp) {
         struct sta_info *sta = link_sta->sta;
 
         if (sta->sdata == sdata ||
             (sta->sdata->bss && sta->sdata->bss == sdata->bss)) {
             rcu_read_unlock();
             /* this is safe as the caller must already hold
              * another rcu read section or the mutex
              */
             return link_sta;
         }
     }
     rcu_read_unlock();
     return NULL;
 }
 
 struct sta_info *sta_info_get_by_addrs(struct ieee80211_local *local,
                        const u8 *sta_addr, const u8 *vif_addr)
 {
     struct rhlist_head *tmp;
     struct sta_info *sta;
 
     for_each_sta_info(local, sta_addr, sta, tmp) {
         if (ether_addr_equal(vif_addr, sta->sdata->vif.addr))
             return sta;
     }
 
     return NULL;
 }
 
 struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata,
                      int idx)
 {
     struct ieee80211_local *local = sdata->local;
     struct sta_info *sta;
     int i = 0;
 
     list_for_each_entry_rcu(sta, &local->sta_list, list,
                 lockdep_is_held(&local->sta_mtx)) {
         if (sdata != sta->sdata)
             continue;
         if (i < idx) {
             ++i;
             continue;
         }
         return sta;
     }
 
     return NULL;
 }
 
 static void sta_info_free_link(struct link_sta_info *link_sta)
 {
     free_percpu(link_sta->pcpu_rx_stats);
 }
 
 static void sta_remove_link(struct sta_info *sta, unsigned int link_id,
                 bool unhash)
 {
     struct sta_link_alloc *alloc = NULL;
     struct link_sta_info *link_sta;
 
     link_sta = rcu_dereference_protected(sta->link[link_id],
                          lockdep_is_held(&sta->local->sta_mtx));
 
     if (WARN_ON(!link_sta))
         return;
 
     if (unhash)
         link_sta_info_hash_del(sta->local, link_sta);
 
     if (link_sta != &sta->deflink)
         alloc = container_of(link_sta, typeof(*alloc), info);
 
     sta->sta.valid_links &= ~BIT(link_id);
     RCU_INIT_POINTER(sta->link[link_id], NULL);
     RCU_INIT_POINTER(sta->sta.link[link_id], NULL);
     if (alloc) {
         sta_info_free_link(&alloc->info);
         kfree_rcu(alloc, rcu_head);
     }
 }
 
 /**
  * sta_info_free - free STA
  *
  * @local: pointer to the global information
  * @sta: STA info to free
  *
  * This function must undo everything done by sta_info_alloc()
  * that may happen before sta_info_insert(). It may only be
  * called when sta_info_insert() has not been attempted (and
  * if that fails, the station is freed anyway.)
  */
 void sta_info_free(struct ieee80211_local *local, struct sta_info *sta)
 {
     int i;
 
     for (i = 0; i < ARRAY_SIZE(sta->link); i++) {
         if (!(sta->sta.valid_links & BIT(i)))
             continue;
 
         sta_remove_link(sta, i, false);
     }
 
     /*
      * If we had used sta_info_pre_move_state() then we might not
      * have gone through the state transitions down again, so do
      * it here now (and warn if it's inserted).
      *
      * This will clear state such as fast TX/RX that may have been
      * allocated during state transitions.
      */
     while (sta->sta_state > IEEE80211_STA_NONE) {
         int ret;
 
         WARN_ON_ONCE(test_sta_flag(sta, WLAN_STA_INSERTED));
 
         ret = sta_info_move_state(sta, sta->sta_state - 1);
         if (WARN_ONCE(ret, "sta_info_move_state() returned %d\n", ret))
             break;
     }
 
     if (sta->rate_ctrl)
         rate_control_free_sta(sta);
 
     sta_dbg(sta->sdata, "Destroyed STA %pM\n", sta->sta.addr);
 
     if (sta->sta.txq[0])
         kfree(to_txq_info(sta->sta.txq[0]));
     kfree(rcu_dereference_raw(sta->sta.rates));
 #ifdef CONFIG_MAC80211_MESH
     kfree(sta->mesh);
 #endif
 
     sta_info_free_link(&sta->deflink);
     kfree(sta);
 }
 
 /* Caller must hold local->sta_mtx */
 static int sta_info_hash_add(struct ieee80211_local *local,
                  struct sta_info *sta)
 {
     return rhltable_insert(&local->sta_hash, &sta->hash_node,
                    sta_rht_params);
 }
 
 static void sta_deliver_ps_frames(struct work_struct *wk)
 {
     struct sta_info *sta;
 
     sta = container_of(wk, struct sta_info, drv_deliver_wk);
 
     if (sta->dead)
         return;
 
     local_bh_disable();
     if (!test_sta_flag(sta, WLAN_STA_PS_STA))
         ieee80211_sta_ps_deliver_wakeup(sta);
     else if (test_and_clear_sta_flag(sta, WLAN_STA_PSPOLL))
         ieee80211_sta_ps_deliver_poll_response(sta);
     else if (test_and_clear_sta_flag(sta, WLAN_STA_UAPSD))
         ieee80211_sta_ps_deliver_uapsd(sta);
     local_bh_enable();
 }
 
 static int sta_prepare_rate_control(struct ieee80211_local *local,
                     struct sta_info *sta, gfp_t gfp)
 {
     if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL))
         return 0;
 
     sta->rate_ctrl = local->rate_ctrl;
     sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl,
                              sta, gfp);
     if (!sta->rate_ctrl_priv)
         return -ENOMEM;
 
     return 0;
 }
 
 static int sta_info_alloc_link(struct ieee80211_local *local,
                    struct link_sta_info *link_info,
                    gfp_t gfp)
 {
     struct ieee80211_hw *hw = &local->hw;
     int i;
 
     if (ieee80211_hw_check(hw, USES_RSS)) {
         link_info->pcpu_rx_stats =
             alloc_percpu_gfp(struct ieee80211_sta_rx_stats, gfp);
         if (!link_info->pcpu_rx_stats)
             return -ENOMEM;
     }
 
     link_info->rx_stats.last_rx = jiffies;
     u64_stats_init(&link_info->rx_stats.syncp);
 
     ewma_signal_init(&link_info->rx_stats_avg.signal);
     ewma_avg_signal_init(&link_info->status_stats.avg_ack_signal);
     for (i = 0; i < ARRAY_SIZE(link_info->rx_stats_avg.chain_signal); i++)
         ewma_signal_init(&link_info->rx_stats_avg.chain_signal[i]);
 
     return 0;
 }
 
 static void sta_info_add_link(struct sta_info *sta,
                   unsigned int link_id,
                   struct link_sta_info *link_info,
                   struct ieee80211_link_sta *link_sta)
 {
     link_info->sta = sta;
     link_info->link_id = link_id;
     link_info->pub = link_sta;
     rcu_assign_pointer(sta->link[link_id], link_info);
     rcu_assign_pointer(sta->sta.link[link_id], link_sta);
 }
 
 static struct sta_info *
 __sta_info_alloc(struct ieee80211_sub_if_data *sdata,
          const u8 *addr, int link_id, const u8 *link_addr,
          gfp_t gfp)
 {
     struct ieee80211_local *local = sdata->local;
     struct ieee80211_hw *hw = &local->hw;
     struct sta_info *sta;
     int i;
 
     sta = kzalloc(sizeof(*sta) + hw->sta_data_size, gfp);
     if (!sta)
         return NULL;
 
     sta->local = local;
     sta->sdata = sdata;
 
     if (sta_info_alloc_link(local, &sta->deflink, gfp))
         goto free;
 
     if (link_id >= 0) {
         sta_info_add_link(sta, link_id, &sta->deflink,
                   &sta->sta.deflink);
         sta->sta.valid_links = BIT(link_id);
     } else {
         sta_info_add_link(sta, 0, &sta->deflink, &sta->sta.deflink);
     }
 
     spin_lock_init(&sta->lock);
     spin_lock_init(&sta->ps_lock);
     INIT_WORK(&sta->drv_deliver_wk, sta_deliver_ps_frames);
     INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work);
     mutex_init(&sta->ampdu_mlme.mtx);
 #ifdef CONFIG_MAC80211_MESH
     if (ieee80211_vif_is_mesh(&sdata->vif)) {
         sta->mesh = kzalloc(sizeof(*sta->mesh), gfp);
         if (!sta->mesh)
             goto free;
         sta->mesh->plink_sta = sta;
         spin_lock_init(&sta->mesh->plink_lock);
         if (!sdata->u.mesh.user_mpm)
             timer_setup(&sta->mesh->plink_timer, mesh_plink_timer,
                     0);
         sta->mesh->nonpeer_pm = NL80211_MESH_POWER_ACTIVE;
     }
 #endif
 
     memcpy(sta->addr, addr, ETH_ALEN);
     memcpy(sta->sta.addr, addr, ETH_ALEN);
     memcpy(sta->deflink.addr, link_addr, ETH_ALEN);
     memcpy(sta->sta.deflink.addr, link_addr, ETH_ALEN);
     sta->sta.max_rx_aggregation_subframes =
         local->hw.max_rx_aggregation_subframes;
 
     /* TODO link specific alloc and assignments for MLO Link STA */
 
     /* Extended Key ID needs to install keys for keyid 0 and 1 Rx-only.
      * The Tx path starts to use a key as soon as the key slot ptk_idx
      * references to is not NULL. To not use the initial Rx-only key
      * prematurely for Tx initialize ptk_idx to an impossible PTK keyid
      * which always will refer to a NULL key.
      */
     BUILD_BUG_ON(ARRAY_SIZE(sta->ptk) <= INVALID_PTK_KEYIDX);
     sta->ptk_idx = INVALID_PTK_KEYIDX;
 
 
     ieee80211_init_frag_cache(&sta->frags);
 
     sta->sta_state = IEEE80211_STA_NONE;
 
     /* Mark TID as unreserved */
     sta->reserved_tid = IEEE80211_TID_UNRESERVED;
 
     sta->last_connected = ktime_get_seconds();
 
     if (local->ops->wake_tx_queue) {
         void *txq_data;
         int size = sizeof(struct txq_info) +
                ALIGN(hw->txq_data_size, sizeof(void *));
 
         txq_data = kcalloc(ARRAY_SIZE(sta->sta.txq), size, gfp);
         if (!txq_data)
             goto free;
 
         for (i = 0; i < ARRAY_SIZE(sta->sta.txq); i++) {
             struct txq_info *txq = txq_data + i * size;
 
             /* might not do anything for the bufferable MMPDU TXQ */
             ieee80211_txq_init(sdata, sta, txq, i);
         }
     }
 
     if (sta_prepare_rate_control(local, sta, gfp))
         goto free_txq;
 
     sta->airtime_weight = IEEE80211_DEFAULT_AIRTIME_WEIGHT;
 
     for (i = 0; i < IEEE80211_NUM_ACS; i++) {
         skb_queue_head_init(&sta->ps_tx_buf[i]);
         skb_queue_head_init(&sta->tx_filtered[i]);
         sta->airtime[i].deficit = sta->airtime_weight;
         atomic_set(&sta->airtime[i].aql_tx_pending, 0);
         sta->airtime[i].aql_limit_low = local->aql_txq_limit_low[i];
         sta->airtime[i].aql_limit_high = local->aql_txq_limit_high[i];
     }
 
     for (i = 0; i < IEEE80211_NUM_TIDS; i++)
         sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX);
 
     for (i = 0; i < NUM_NL80211_BANDS; i++) {
         u32 mandatory = 0;
         int r;
 
         if (!hw->wiphy->bands[i])
             continue;
 
         switch (i) {
         case NL80211_BAND_2GHZ:
         case NL80211_BAND_LC:
             /*
              * We use both here, even if we cannot really know for
              * sure the station will support both, but the only use
              * for this is when we don't know anything yet and send
              * management frames, and then we'll pick the lowest
              * possible rate anyway.
              * If we don't include _G here, we cannot find a rate
              * in P2P, and thus trigger the WARN_ONCE() in rate.c
              */
             mandatory = IEEE80211_RATE_MANDATORY_B |
                     IEEE80211_RATE_MANDATORY_G;
             break;
         case NL80211_BAND_5GHZ:
             mandatory = IEEE80211_RATE_MANDATORY_A;
             break;
         case NL80211_BAND_60GHZ:
             WARN_ON(1);
             mandatory = 0;
             break;
         }
 
         for (r = 0; r < hw->wiphy->bands[i]->n_bitrates; r++) {
             struct ieee80211_rate *rate;
 
             rate = &hw->wiphy->bands[i]->bitrates[r];
 
             if (!(rate->flags & mandatory))
                 continue;
             sta->sta.deflink.supp_rates[i] |= BIT(r);
         }
     }
 
     sta->sta.smps_mode = IEEE80211_SMPS_OFF;
     sta->sta.max_rc_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_BA;
 
     sta->cparams.ce_threshold = CODEL_DISABLED_THRESHOLD;
     sta->cparams.target = MS2TIME(20);
     sta->cparams.interval = MS2TIME(100);
     sta->cparams.ecn = true;
     sta->cparams.ce_threshold_selector = 0;
     sta->cparams.ce_threshold_mask = 0;
 
     sta_dbg(sdata, "Allocated STA %pM\n", sta->sta.addr);
 
     return sta;
 
 free_txq:
     if (sta->sta.txq[0])
         kfree(to_txq_info(sta->sta.txq[0]));
 free:
     sta_info_free_link(&sta->deflink);
 #ifdef CONFIG_MAC80211_MESH
     kfree(sta->mesh);
 #endif
     kfree(sta);
     return NULL;
 }
 
 struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
                 const u8 *addr, gfp_t gfp)
 {
     return __sta_info_alloc(sdata, addr, -1, addr, gfp);
 }
 
 struct sta_info *sta_info_alloc_with_link(struct ieee80211_sub_if_data *sdata,
                       const u8 *mld_addr,
                       unsigned int link_id,
                       const u8 *link_addr,
                       gfp_t gfp)
 {
     return __sta_info_alloc(sdata, mld_addr, link_id, link_addr, gfp);
 }
 
 static int sta_info_insert_check(struct sta_info *sta)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
 
     /*
      * Can't be a WARN_ON because it can be triggered through a race:
      * something inserts a STA (on one CPU) without holding the RTNL
      * and another CPU turns off the net device.
      */
     if (unlikely(!ieee80211_sdata_running(sdata)))
         return -ENETDOWN;
 
     if (WARN_ON(ether_addr_equal(sta->sta.addr, sdata->vif.addr) ||
             !is_valid_ether_addr(sta->sta.addr)))
         return -EINVAL;
 
     /* The RCU read lock is required by rhashtable due to
      * asynchronous resize/rehash.  We also require the mutex
      * for correctness.
      */
     rcu_read_lock();
     lockdep_assert_held(&sdata->local->sta_mtx);
     if (ieee80211_hw_check(&sdata->local->hw, NEEDS_UNIQUE_STA_ADDR) &&
         ieee80211_find_sta_by_ifaddr(&sdata->local->hw, sta->addr, NULL)) {
         rcu_read_unlock();
         return -ENOTUNIQ;
     }
     rcu_read_unlock();
 
     return 0;
 }
 
 static int sta_info_insert_drv_state(struct ieee80211_local *local,
                      struct ieee80211_sub_if_data *sdata,
                      struct sta_info *sta)
 {
     enum ieee80211_sta_state state;
     int err = 0;
 
     for (state = IEEE80211_STA_NOTEXIST; state < sta->sta_state; state++) {
         err = drv_sta_state(local, sdata, sta, state, state + 1);
         if (err)
             break;
     }
 
     if (!err) {
         /*
          * Drivers using legacy sta_add/sta_remove callbacks only
          * get uploaded set to true after sta_add is called.
          */
         if (!local->ops->sta_add)
             sta->uploaded = true;
         return 0;
     }
 
     if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
         sdata_info(sdata,
                "failed to move IBSS STA %pM to state %d (%d) - keeping it anyway\n",
                sta->sta.addr, state + 1, err);
         err = 0;
     }
 
     /* unwind on error */
     for (; state > IEEE80211_STA_NOTEXIST; state--)
         WARN_ON(drv_sta_state(local, sdata, sta, state, state - 1));
 
     return err;
 }
 
 static void
 ieee80211_recalc_p2p_go_ps_allowed(struct ieee80211_sub_if_data *sdata)
 {
     struct ieee80211_local *local = sdata->local;
     bool allow_p2p_go_ps = sdata->vif.p2p;
     struct sta_info *sta;
 
     rcu_read_lock();
     list_for_each_entry_rcu(sta, &local->sta_list, list) {
         if (sdata != sta->sdata ||
             !test_sta_flag(sta, WLAN_STA_ASSOC))
             continue;
         if (!sta->sta.support_p2p_ps) {
             allow_p2p_go_ps = false;
             break;
         }
     }
     rcu_read_unlock();
 
     if (allow_p2p_go_ps != sdata->vif.bss_conf.allow_p2p_go_ps) {
         sdata->vif.bss_conf.allow_p2p_go_ps = allow_p2p_go_ps;
         ieee80211_link_info_change_notify(sdata, &sdata->deflink,
                           BSS_CHANGED_P2P_PS);
     }
 }
 
 /*
  * should be called with sta_mtx locked
  * this function replaces the mutex lock
  * with a RCU lock
  */
 static int sta_info_insert_finish(struct sta_info *sta) __acquires(RCU)
 {
     struct ieee80211_local *local = sta->local;
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct station_info *sinfo = NULL;
     int err = 0;
 
     lockdep_assert_held(&local->sta_mtx);
 
     /* check if STA exists already */
     if (sta_info_get_bss(sdata, sta->sta.addr)) {
         err = -EEXIST;
         goto out_cleanup;
     }
 
     sinfo = kzalloc(sizeof(struct station_info), GFP_KERNEL);
     if (!sinfo) {
         err = -ENOMEM;
         goto out_cleanup;
     }
 
     local->num_sta++;
     local->sta_generation++;
     smp_mb();
 
     /* simplify things and don't accept BA sessions yet */
     set_sta_flag(sta, WLAN_STA_BLOCK_BA);
 
     /* make the station visible */
     err = sta_info_hash_add(local, sta);
     if (err)
         goto out_drop_sta;
 
     if (sta->sta.valid_links) {
         err = link_sta_info_hash_add(local, &sta->deflink);
         if (err) {
             sta_info_hash_del(local, sta);
             goto out_drop_sta;
         }
     }
 
     list_add_tail_rcu(&sta->list, &local->sta_list);
 
     /* update channel context before notifying the driver about state
      * change, this enables driver using the updated channel context right away.
      */
     if (sta->sta_state >= IEEE80211_STA_ASSOC) {
         ieee80211_recalc_min_chandef(sta->sdata, -1);
         if (!sta->sta.support_p2p_ps)
             ieee80211_recalc_p2p_go_ps_allowed(sta->sdata);
     }
 
     /* notify driver */
     err = sta_info_insert_drv_state(local, sdata, sta);
     if (err)
         goto out_remove;
 
     set_sta_flag(sta, WLAN_STA_INSERTED);
 
     /* accept BA sessions now */
     clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
 
     ieee80211_sta_debugfs_add(sta);
     rate_control_add_sta_debugfs(sta);
 
     sinfo->generation = local->sta_generation;
     cfg80211_new_sta(sdata->dev, sta->sta.addr, sinfo, GFP_KERNEL);
     kfree(sinfo);
 
     sta_dbg(sdata, "Inserted STA %pM\n", sta->sta.addr);
 
     /* move reference to rcu-protected */
     rcu_read_lock();
     mutex_unlock(&local->sta_mtx);
 
     if (ieee80211_vif_is_mesh(&sdata->vif))
         mesh_accept_plinks_update(sdata);
 
     return 0;
  out_remove:
     if (sta->sta.valid_links)
         link_sta_info_hash_del(local, &sta->deflink);
     sta_info_hash_del(local, sta);
     list_del_rcu(&sta->list);
  out_drop_sta:
     local->num_sta--;
     synchronize_net();
  out_cleanup:
     cleanup_single_sta(sta);
     mutex_unlock(&local->sta_mtx);
     kfree(sinfo);
     rcu_read_lock();
     return err;
 }
 
 int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU)
 {
     struct ieee80211_local *local = sta->local;
     int err;
 
     might_sleep();
 
     mutex_lock(&local->sta_mtx);
 
     err = sta_info_insert_check(sta);
     if (err) {
         sta_info_free(local, sta);
         mutex_unlock(&local->sta_mtx);
         rcu_read_lock();
         return err;
     }
 
     return sta_info_insert_finish(sta);
 }
 
 int sta_info_insert(struct sta_info *sta)
 {
     int err = sta_info_insert_rcu(sta);
 
     rcu_read_unlock();
 
     return err;
 }
 
 static inline void __bss_tim_set(u8 *tim, u16 id)
 {
     /*
      * This format has been mandated by the IEEE specifications,
      * so this line may not be changed to use the __set_bit() format.
      */
     tim[id / 8] |= (1 << (id % 8));
 }
 
 static inline void __bss_tim_clear(u8 *tim, u16 id)
 {
     /*
      * This format has been mandated by the IEEE specifications,
      * so this line may not be changed to use the __clear_bit() format.
      */
     tim[id / 8] &= ~(1 << (id % 8));
 }
 
 static inline bool __bss_tim_get(u8 *tim, u16 id)
 {
     /*
      * This format has been mandated by the IEEE specifications,
      * so this line may not be changed to use the test_bit() format.
      */
     return tim[id / 8] & (1 << (id % 8));
 }
 
 static unsigned long ieee80211_tids_for_ac(int ac)
 {
     /* If we ever support TIDs > 7, this obviously needs to be adjusted */
     switch (ac) {
     case IEEE80211_AC_VO:
         return BIT(6) | BIT(7);
     case IEEE80211_AC_VI:
         return BIT(4) | BIT(5);
     case IEEE80211_AC_BE:
         return BIT(0) | BIT(3);
     case IEEE80211_AC_BK:
         return BIT(1) | BIT(2);
     default:
         WARN_ON(1);
         return 0;
     }
 }
 
 static void __sta_info_recalc_tim(struct sta_info *sta, bool ignore_pending)
 {
     struct ieee80211_local *local = sta->local;
     struct ps_data *ps;
     bool indicate_tim = false;
     u8 ignore_for_tim = sta->sta.uapsd_queues;
     int ac;
     u16 id = sta->sta.aid;
 
     if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
         sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
         if (WARN_ON_ONCE(!sta->sdata->bss))
             return;
 
         ps = &sta->sdata->bss->ps;
 #ifdef CONFIG_MAC80211_MESH
     } else if (ieee80211_vif_is_mesh(&sta->sdata->vif)) {
         ps = &sta->sdata->u.mesh.ps;
 #endif
     } else {
         return;
     }
 
     /* No need to do anything if the driver does all */
     if (ieee80211_hw_check(&local->hw, AP_LINK_PS) && !local->ops->set_tim)
         return;
 
     if (sta->dead)
         goto done;
 
     /*
      * If all ACs are delivery-enabled then we should build
      * the TIM bit for all ACs anyway; if only some are then
      * we ignore those and build the TIM bit using only the
      * non-enabled ones.
      */
     if (ignore_for_tim == BIT(IEEE80211_NUM_ACS) - 1)
         ignore_for_tim = 0;
 
     if (ignore_pending)
         ignore_for_tim = BIT(IEEE80211_NUM_ACS) - 1;
 
     for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
         unsigned long tids;
 
         if (ignore_for_tim & ieee80211_ac_to_qos_mask[ac])
             continue;
 
         indicate_tim |= !skb_queue_empty(&sta->tx_filtered[ac]) ||
                 !skb_queue_empty(&sta->ps_tx_buf[ac]);
         if (indicate_tim)
             break;
 
         tids = ieee80211_tids_for_ac(ac);
 
         indicate_tim |=
             sta->driver_buffered_tids & tids;
         indicate_tim |=
             sta->txq_buffered_tids & tids;
     }
 
  done:
     spin_lock_bh(&local->tim_lock);
 
     if (indicate_tim == __bss_tim_get(ps->tim, id))
         goto out_unlock;
 
     if (indicate_tim)
         __bss_tim_set(ps->tim, id);
     else
         __bss_tim_clear(ps->tim, id);
 
     if (local->ops->set_tim && !WARN_ON(sta->dead)) {
         local->tim_in_locked_section = true;
         drv_set_tim(local, &sta->sta, indicate_tim);
         local->tim_in_locked_section = false;
     }
 
 out_unlock:
     spin_unlock_bh(&local->tim_lock);
 }
 
 void sta_info_recalc_tim(struct sta_info *sta)
 {
     __sta_info_recalc_tim(sta, false);
 }
 
 static bool sta_info_buffer_expired(struct sta_info *sta, struct sk_buff *skb)
 {
     struct ieee80211_tx_info *info;
     int timeout;
 
     if (!skb)
         return false;
 
     info = IEEE80211_SKB_CB(skb);
 
     /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */
     timeout = (sta->listen_interval *
            sta->sdata->vif.bss_conf.beacon_int *
            32 / 15625) * HZ;
     if (timeout < STA_TX_BUFFER_EXPIRE)
         timeout = STA_TX_BUFFER_EXPIRE;
     return time_after(jiffies, info->control.jiffies + timeout);
 }
 
 
 static bool sta_info_cleanup_expire_buffered_ac(struct ieee80211_local *local,
                         struct sta_info *sta, int ac)
 {
     unsigned long flags;
     struct sk_buff *skb;
 
     /*
      * First check for frames that should expire on the filtered
      * queue. Frames here were rejected by the driver and are on
      * a separate queue to avoid reordering with normal PS-buffered
      * frames. They also aren't accounted for right now in the
      * total_ps_buffered counter.
      */
     for (;;) {
         spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags);
         skb = skb_peek(&sta->tx_filtered[ac]);
         if (sta_info_buffer_expired(sta, skb))
             skb = __skb_dequeue(&sta->tx_filtered[ac]);
         else
             skb = NULL;
         spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags);
 
         /*
          * Frames are queued in order, so if this one
          * hasn't expired yet we can stop testing. If
          * we actually reached the end of the queue we
          * also need to stop, of course.
          */
         if (!skb)
             break;
         ieee80211_free_txskb(&local->hw, skb);
     }
 
     /*
      * Now also check the normal PS-buffered queue, this will
      * only find something if the filtered queue was emptied
      * since the filtered frames are all before the normal PS
      * buffered frames.
      */
     for (;;) {
         spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags);
         skb = skb_peek(&sta->ps_tx_buf[ac]);
         if (sta_info_buffer_expired(sta, skb))
             skb = __skb_dequeue(&sta->ps_tx_buf[ac]);
         else
             skb = NULL;
         spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags);
 
         /*
          * frames are queued in order, so if this one
          * hasn't expired yet (or we reached the end of
          * the queue) we can stop testing
          */
         if (!skb)
             break;
 
         local->total_ps_buffered--;
         ps_dbg(sta->sdata, "Buffered frame expired (STA %pM)\n",
                sta->sta.addr);
         ieee80211_free_txskb(&local->hw, skb);
     }
 
     /*
      * Finally, recalculate the TIM bit for this station -- it might
      * now be clear because the station was too slow to retrieve its
      * frames.
      */
     sta_info_recalc_tim(sta);
 
     /*
      * Return whether there are any frames still buffered, this is
      * used to check whether the cleanup timer still needs to run,
      * if there are no frames we don't need to rearm the timer.
      */
     return !(skb_queue_empty(&sta->ps_tx_buf[ac]) &&
          skb_queue_empty(&sta->tx_filtered[ac]));
 }
 
 static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
                          struct sta_info *sta)
 {
     bool have_buffered = false;
     int ac;
 
     /* This is only necessary for stations on BSS/MBSS interfaces */
     if (!sta->sdata->bss &&
         !ieee80211_vif_is_mesh(&sta->sdata->vif))
         return false;
 
     for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
         have_buffered |=
             sta_info_cleanup_expire_buffered_ac(local, sta, ac);
 
     return have_buffered;
 }
 
 static int __must_check __sta_info_destroy_part1(struct sta_info *sta)
 {
     struct ieee80211_local *local;
     struct ieee80211_sub_if_data *sdata;
     int ret, i;
 
     might_sleep();
 
     if (!sta)
         return -ENOENT;
 
     local = sta->local;
     sdata = sta->sdata;
 
     lockdep_assert_held(&local->sta_mtx);
 
     /*
      * Before removing the station from the driver and
      * rate control, it might still start new aggregation
      * sessions -- block that to make sure the tear-down
      * will be sufficient.
      */
     set_sta_flag(sta, WLAN_STA_BLOCK_BA);
     ieee80211_sta_tear_down_BA_sessions(sta, AGG_STOP_DESTROY_STA);
 
     /*
      * Before removing the station from the driver there might be pending
      * rx frames on RSS queues sent prior to the disassociation - wait for
      * all such frames to be processed.
      */
     drv_sync_rx_queues(local, sta);
 
     for (i = 0; i < ARRAY_SIZE(sta->link); i++) {
         struct link_sta_info *link_sta;
 
         if (!(sta->sta.valid_links & BIT(i)))
             continue;
 
         link_sta = rcu_dereference_protected(sta->link[i],
                              lockdep_is_held(&local->sta_mtx));
 
         link_sta_info_hash_del(local, link_sta);
     }
 
     ret = sta_info_hash_del(local, sta);
     if (WARN_ON(ret))
         return ret;
 
     /*
      * for TDLS peers, make sure to return to the base channel before
      * removal.
      */
     if (test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
         drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
         clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
     }
 
     list_del_rcu(&sta->list);
     sta->removed = true;
 
     drv_sta_pre_rcu_remove(local, sta->sdata, sta);
 
     if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
         rcu_access_pointer(sdata->u.vlan.sta) == sta)
         RCU_INIT_POINTER(sdata->u.vlan.sta, NULL);
 
     return 0;
 }
 
 static void __sta_info_destroy_part2(struct sta_info *sta)
 {
     struct ieee80211_local *local = sta->local;
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct station_info *sinfo;
     int ret;
 
     /*
      * NOTE: This assumes at least synchronize_net() was done
      *   after _part1 and before _part2!
      */
 
     might_sleep();
     lockdep_assert_held(&local->sta_mtx);
 
     if (sta->sta_state == IEEE80211_STA_AUTHORIZED) {
         ret = sta_info_move_state(sta, IEEE80211_STA_ASSOC);
         WARN_ON_ONCE(ret);
     }
 
     /* now keys can no longer be reached */
     ieee80211_free_sta_keys(local, sta);
 
     /* disable TIM bit - last chance to tell driver */
     __sta_info_recalc_tim(sta, true);
 
     sta->dead = true;
 
     local->num_sta--;
     local->sta_generation++;
 
     while (sta->sta_state > IEEE80211_STA_NONE) {
         ret = sta_info_move_state(sta, sta->sta_state - 1);
         if (ret) {
             WARN_ON_ONCE(1);
             break;
         }
     }
 
     if (sta->uploaded) {
         ret = drv_sta_state(local, sdata, sta, IEEE80211_STA_NONE,
                     IEEE80211_STA_NOTEXIST);
         WARN_ON_ONCE(ret != 0);
     }
 
     sta_dbg(sdata, "Removed STA %pM\n", sta->sta.addr);
 
     sinfo = kzalloc(sizeof(*sinfo), GFP_KERNEL);
     if (sinfo)
         sta_set_sinfo(sta, sinfo, true);
     cfg80211_del_sta_sinfo(sdata->dev, sta->sta.addr, sinfo, GFP_KERNEL);
     kfree(sinfo);
 
     ieee80211_sta_debugfs_remove(sta);
 
     ieee80211_destroy_frag_cache(&sta->frags);
 
     cleanup_single_sta(sta);
 }
 
 int __must_check __sta_info_destroy(struct sta_info *sta)
 {
     int err = __sta_info_destroy_part1(sta);
 
     if (err)
         return err;
 
     synchronize_net();
 
     __sta_info_destroy_part2(sta);
 
     return 0;
 }
 
 int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr)
 {
     struct sta_info *sta;
     int ret;
 
     mutex_lock(&sdata->local->sta_mtx);
     sta = sta_info_get(sdata, addr);
     ret = __sta_info_destroy(sta);
     mutex_unlock(&sdata->local->sta_mtx);
 
     return ret;
 }
 
 int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata,
                   const u8 *addr)
 {
     struct sta_info *sta;
     int ret;
 
     mutex_lock(&sdata->local->sta_mtx);
     sta = sta_info_get_bss(sdata, addr);
     ret = __sta_info_destroy(sta);
     mutex_unlock(&sdata->local->sta_mtx);
 
     return ret;
 }
 
 static void sta_info_cleanup(struct timer_list *t)
 {
     struct ieee80211_local *local = from_timer(local, t, sta_cleanup);
     struct sta_info *sta;
     bool timer_needed = false;
 
     rcu_read_lock();
     list_for_each_entry_rcu(sta, &local->sta_list, list)
         if (sta_info_cleanup_expire_buffered(local, sta))
             timer_needed = true;
     rcu_read_unlock();
 
     if (local->quiescing)
         return;
 
     if (!timer_needed)
         return;
 
     mod_timer(&local->sta_cleanup,
           round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL));
 }
 
 int sta_info_init(struct ieee80211_local *local)
 {
     int err;
 
     err = rhltable_init(&local->sta_hash, &sta_rht_params);
     if (err)
         return err;
 
     err = rhltable_init(&local->link_sta_hash, &link_sta_rht_params);
     if (err) {
         rhltable_destroy(&local->sta_hash);
         return err;
     }
 
     spin_lock_init(&local->tim_lock);
     mutex_init(&local->sta_mtx);
     INIT_LIST_HEAD(&local->sta_list);
 
     timer_setup(&local->sta_cleanup, sta_info_cleanup, 0);
     return 0;
 }
 
 void sta_info_stop(struct ieee80211_local *local)
 {
     del_timer_sync(&local->sta_cleanup);
     rhltable_destroy(&local->sta_hash);
     rhltable_destroy(&local->link_sta_hash);
 }
 
 
 int __sta_info_flush(struct ieee80211_sub_if_data *sdata, bool vlans)
 {
     struct ieee80211_local *local = sdata->local;
     struct sta_info *sta, *tmp;
     LIST_HEAD(free_list);
     int ret = 0;
 
     might_sleep();
 
     WARN_ON(vlans && sdata->vif.type != NL80211_IFTYPE_AP);
     WARN_ON(vlans && !sdata->bss);
 
     mutex_lock(&local->sta_mtx);
     list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
         if (sdata == sta->sdata ||
             (vlans && sdata->bss == sta->sdata->bss)) {
             if (!WARN_ON(__sta_info_destroy_part1(sta)))
                 list_add(&sta->free_list, &free_list);
             ret++;
         }
     }
 
     if (!list_empty(&free_list)) {
         synchronize_net();
         list_for_each_entry_safe(sta, tmp, &free_list, free_list)
             __sta_info_destroy_part2(sta);
     }
     mutex_unlock(&local->sta_mtx);
 
     return ret;
 }
 
 void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
               unsigned long exp_time)
 {
     struct ieee80211_local *local = sdata->local;
     struct sta_info *sta, *tmp;
 
     mutex_lock(&local->sta_mtx);
 
     list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
         unsigned long last_active = ieee80211_sta_last_active(sta);
 
         if (sdata != sta->sdata)
             continue;
 
         if (time_is_before_jiffies(last_active + exp_time)) {
             sta_dbg(sta->sdata, "expiring inactive STA %pM\n",
                 sta->sta.addr);
 
             if (ieee80211_vif_is_mesh(&sdata->vif) &&
                 test_sta_flag(sta, WLAN_STA_PS_STA))
                 atomic_dec(&sdata->u.mesh.ps.num_sta_ps);
 
             WARN_ON(__sta_info_destroy(sta));
         }
     }
 
     mutex_unlock(&local->sta_mtx);
 }
 
 struct ieee80211_sta *ieee80211_find_sta_by_ifaddr(struct ieee80211_hw *hw,
                            const u8 *addr,
                            const u8 *localaddr)
 {
     struct ieee80211_local *local = hw_to_local(hw);
     struct rhlist_head *tmp;
     struct sta_info *sta;
 
     /*
      * Just return a random station if localaddr is NULL
      * ... first in list.
      */
     for_each_sta_info(local, addr, sta, tmp) {
         if (localaddr &&
             !ether_addr_equal(sta->sdata->vif.addr, localaddr))
             continue;
         if (!sta->uploaded)
             return NULL;
         return &sta->sta;
     }
 
     return NULL;
 }
 EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_ifaddr);
 
 struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif,
                      const u8 *addr)
 {
     struct sta_info *sta;
 
     if (!vif)
         return NULL;
 
     sta = sta_info_get_bss(vif_to_sdata(vif), addr);
     if (!sta)
         return NULL;
 
     if (!sta->uploaded)
         return NULL;
 
     return &sta->sta;
 }
 EXPORT_SYMBOL(ieee80211_find_sta);
 
 /* powersave support code */
 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct ieee80211_local *local = sdata->local;
     struct sk_buff_head pending;
     int filtered = 0, buffered = 0, ac, i;
     unsigned long flags;
     struct ps_data *ps;
 
     if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
         sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
                      u.ap);
 
     if (sdata->vif.type == NL80211_IFTYPE_AP)
         ps = &sdata->bss->ps;
     else if (ieee80211_vif_is_mesh(&sdata->vif))
         ps = &sdata->u.mesh.ps;
     else
         return;
 
     clear_sta_flag(sta, WLAN_STA_SP);
 
     BUILD_BUG_ON(BITS_TO_LONGS(IEEE80211_NUM_TIDS) > 1);
     sta->driver_buffered_tids = 0;
     sta->txq_buffered_tids = 0;
 
     if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
         drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
 
     for (i = 0; i < ARRAY_SIZE(sta->sta.txq); i++) {
         if (!sta->sta.txq[i] || !txq_has_queue(sta->sta.txq[i]))
             continue;
 
         schedule_and_wake_txq(local, to_txq_info(sta->sta.txq[i]));
     }
 
     skb_queue_head_init(&pending);
 
     /* sync with ieee80211_tx_h_unicast_ps_buf */
     spin_lock(&sta->ps_lock);
     /* Send all buffered frames to the station */
     for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
         int count = skb_queue_len(&pending), tmp;
 
         spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags);
         skb_queue_splice_tail_init(&sta->tx_filtered[ac], &pending);
         spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags);
         tmp = skb_queue_len(&pending);
         filtered += tmp - count;
         count = tmp;
 
         spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags);
         skb_queue_splice_tail_init(&sta->ps_tx_buf[ac], &pending);
         spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags);
         tmp = skb_queue_len(&pending);
         buffered += tmp - count;
     }
 
     ieee80211_add_pending_skbs(local, &pending);
 
     /* now we're no longer in the deliver code */
     clear_sta_flag(sta, WLAN_STA_PS_DELIVER);
 
     /* The station might have polled and then woken up before we responded,
      * so clear these flags now to avoid them sticking around.
      */
     clear_sta_flag(sta, WLAN_STA_PSPOLL);
     clear_sta_flag(sta, WLAN_STA_UAPSD);
     spin_unlock(&sta->ps_lock);
 
     atomic_dec(&ps->num_sta_ps);
 
     local->total_ps_buffered -= buffered;
 
     sta_info_recalc_tim(sta);
 
     ps_dbg(sdata,
            "STA %pM aid %d sending %d filtered/%d PS frames since STA woke up\n",
            sta->sta.addr, sta->sta.aid, filtered, buffered);
 
     ieee80211_check_fast_xmit(sta);
 }
 
 static void ieee80211_send_null_response(struct sta_info *sta, int tid,
                      enum ieee80211_frame_release_type reason,
                      bool call_driver, bool more_data)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct ieee80211_local *local = sdata->local;
     struct ieee80211_qos_hdr *nullfunc;
     struct sk_buff *skb;
     int size = sizeof(*nullfunc);
     __le16 fc;
     bool qos = sta->sta.wme;
     struct ieee80211_tx_info *info;
     struct ieee80211_chanctx_conf *chanctx_conf;
 
     if (qos) {
         fc = cpu_to_le16(IEEE80211_FTYPE_DATA |
                  IEEE80211_STYPE_QOS_NULLFUNC |
                  IEEE80211_FCTL_FROMDS);
     } else {
         size -= 2;
         fc = cpu_to_le16(IEEE80211_FTYPE_DATA |
                  IEEE80211_STYPE_NULLFUNC |
                  IEEE80211_FCTL_FROMDS);
     }
 
     skb = dev_alloc_skb(local->hw.extra_tx_headroom + size);
     if (!skb)
         return;
 
     skb_reserve(skb, local->hw.extra_tx_headroom);
 
     nullfunc = skb_put(skb, size);
     nullfunc->frame_control = fc;
     nullfunc->duration_id = 0;
     memcpy(nullfunc->addr1, sta->sta.addr, ETH_ALEN);
     memcpy(nullfunc->addr2, sdata->vif.addr, ETH_ALEN);
     memcpy(nullfunc->addr3, sdata->vif.addr, ETH_ALEN);
     nullfunc->seq_ctrl = 0;
 
     skb->priority = tid;
     skb_set_queue_mapping(skb, ieee802_1d_to_ac[tid]);
     if (qos) {
         nullfunc->qos_ctrl = cpu_to_le16(tid);
 
         if (reason == IEEE80211_FRAME_RELEASE_UAPSD) {
             nullfunc->qos_ctrl |=
                 cpu_to_le16(IEEE80211_QOS_CTL_EOSP);
             if (more_data)
                 nullfunc->frame_control |=
                     cpu_to_le16(IEEE80211_FCTL_MOREDATA);
         }
     }
 
     info = IEEE80211_SKB_CB(skb);
 
     /*
      * Tell TX path to send this frame even though the
      * STA may still remain is PS mode after this frame
      * exchange. Also set EOSP to indicate this packet
      * ends the poll/service period.
      */
     info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER |
                IEEE80211_TX_STATUS_EOSP |
                IEEE80211_TX_CTL_REQ_TX_STATUS;
 
     info->control.flags |= IEEE80211_TX_CTRL_PS_RESPONSE;
 
     if (call_driver)
         drv_allow_buffered_frames(local, sta, BIT(tid), 1,
                       reason, false);
 
     skb->dev = sdata->dev;
 
     rcu_read_lock();
     chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
     if (WARN_ON(!chanctx_conf)) {
         rcu_read_unlock();
         kfree_skb(skb);
         return;
     }
 
     info->band = chanctx_conf->def.chan->band;
     ieee80211_xmit(sdata, sta, skb);
     rcu_read_unlock();
 }
 
 static int find_highest_prio_tid(unsigned long tids)
 {
     /* lower 3 TIDs aren't ordered perfectly */
     if (tids & 0xF8)
         return fls(tids) - 1;
     /* TID 0 is BE just like TID 3 */
     if (tids & BIT(0))
         return 0;
     return fls(tids) - 1;
 }
 
 /* Indicates if the MORE_DATA bit should be set in the last
  * frame obtained by ieee80211_sta_ps_get_frames.
  * Note that driver_release_tids is relevant only if
  * reason = IEEE80211_FRAME_RELEASE_PSPOLL
  */
 static bool
 ieee80211_sta_ps_more_data(struct sta_info *sta, u8 ignored_acs,
                enum ieee80211_frame_release_type reason,
                unsigned long driver_release_tids)
 {
     int ac;
 
     /* If the driver has data on more than one TID then
      * certainly there's more data if we release just a
      * single frame now (from a single TID). This will
      * only happen for PS-Poll.
      */
     if (reason == IEEE80211_FRAME_RELEASE_PSPOLL &&
         hweight16(driver_release_tids) > 1)
         return true;
 
     for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
         if (ignored_acs & ieee80211_ac_to_qos_mask[ac])
             continue;
 
         if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
             !skb_queue_empty(&sta->ps_tx_buf[ac]))
             return true;
     }
 
     return false;
 }
 
 static void
 ieee80211_sta_ps_get_frames(struct sta_info *sta, int n_frames, u8 ignored_acs,
                 enum ieee80211_frame_release_type reason,
                 struct sk_buff_head *frames,
                 unsigned long *driver_release_tids)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct ieee80211_local *local = sdata->local;
     int ac;
 
     /* Get response frame(s) and more data bit for the last one. */
     for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
         unsigned long tids;
 
         if (ignored_acs & ieee80211_ac_to_qos_mask[ac])
             continue;
 
         tids = ieee80211_tids_for_ac(ac);
 
         /* if we already have frames from software, then we can't also
          * release from hardware queues
          */
         if (skb_queue_empty(frames)) {
             *driver_release_tids |=
                 sta->driver_buffered_tids & tids;
             *driver_release_tids |= sta->txq_buffered_tids & tids;
         }
 
         if (!*driver_release_tids) {
             struct sk_buff *skb;
 
             while (n_frames > 0) {
                 skb = skb_dequeue(&sta->tx_filtered[ac]);
                 if (!skb) {
                     skb = skb_dequeue(
                         &sta->ps_tx_buf[ac]);
                     if (skb)
                         local->total_ps_buffered--;
                 }
                 if (!skb)
                     break;
                 n_frames--;
                 __skb_queue_tail(frames, skb);
             }
         }
 
         /* If we have more frames buffered on this AC, then abort the
          * loop since we can't send more data from other ACs before
          * the buffered frames from this.
          */
         if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
             !skb_queue_empty(&sta->ps_tx_buf[ac]))
             break;
     }
 }
 
 static void
 ieee80211_sta_ps_deliver_response(struct sta_info *sta,
                   int n_frames, u8 ignored_acs,
                   enum ieee80211_frame_release_type reason)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct ieee80211_local *local = sdata->local;
     unsigned long driver_release_tids = 0;
     struct sk_buff_head frames;
     bool more_data;
 
     /* Service or PS-Poll period starts */
     set_sta_flag(sta, WLAN_STA_SP);
 
     __skb_queue_head_init(&frames);
 
     ieee80211_sta_ps_get_frames(sta, n_frames, ignored_acs, reason,
                     &frames, &driver_release_tids);
 
     more_data = ieee80211_sta_ps_more_data(sta, ignored_acs, reason, driver_release_tids);
 
     if (driver_release_tids && reason == IEEE80211_FRAME_RELEASE_PSPOLL)
         driver_release_tids =
             BIT(find_highest_prio_tid(driver_release_tids));
 
     if (skb_queue_empty(&frames) && !driver_release_tids) {
         int tid, ac;
 
         /*
          * For PS-Poll, this can only happen due to a race condition
          * when we set the TIM bit and the station notices it, but
          * before it can poll for the frame we expire it.
          *
          * For uAPSD, this is said in the standard (11.2.1.5 h):
          *  At each unscheduled SP for a non-AP STA, the AP shall
          *  attempt to transmit at least one MSDU or MMPDU, but no
          *  more than the value specified in the Max SP Length field
          *  in the QoS Capability element from delivery-enabled ACs,
          *  that are destined for the non-AP STA.
          *
          * Since we have no other MSDU/MMPDU, transmit a QoS null frame.
          */
 
         /* This will evaluate to 1, 3, 5 or 7. */
         for (ac = IEEE80211_AC_VO; ac < IEEE80211_NUM_ACS; ac++)
             if (!(ignored_acs & ieee80211_ac_to_qos_mask[ac]))
                 break;
         tid = 7 - 2 * ac;
 
         ieee80211_send_null_response(sta, tid, reason, true, false);
     } else if (!driver_release_tids) {
         struct sk_buff_head pending;
         struct sk_buff *skb;
         int num = 0;
         u16 tids = 0;
         bool need_null = false;
 
         skb_queue_head_init(&pending);
 
         while ((skb = __skb_dequeue(&frames))) {
             struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
             struct ieee80211_hdr *hdr = (void *) skb->data;
             u8 *qoshdr = NULL;
 
             num++;
 
             /*
              * Tell TX path to send this frame even though the
              * STA may still remain is PS mode after this frame
              * exchange.
              */
             info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
             info->control.flags |= IEEE80211_TX_CTRL_PS_RESPONSE;
 
             /*
              * Use MoreData flag to indicate whether there are
              * more buffered frames for this STA
              */
             if (more_data || !skb_queue_empty(&frames))
                 hdr->frame_control |=
                     cpu_to_le16(IEEE80211_FCTL_MOREDATA);
             else
                 hdr->frame_control &=
                     cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 
             if (ieee80211_is_data_qos(hdr->frame_control) ||
                 ieee80211_is_qos_nullfunc(hdr->frame_control))
                 qoshdr = ieee80211_get_qos_ctl(hdr);
 
             tids |= BIT(skb->priority);
 
             __skb_queue_tail(&pending, skb);
 
             /* end service period after last frame or add one */
             if (!skb_queue_empty(&frames))
                 continue;
 
             if (reason != IEEE80211_FRAME_RELEASE_UAPSD) {
                 /* for PS-Poll, there's only one frame */
                 info->flags |= IEEE80211_TX_STATUS_EOSP |
                            IEEE80211_TX_CTL_REQ_TX_STATUS;
                 break;
             }
 
             /* For uAPSD, things are a bit more complicated. If the
              * last frame has a QoS header (i.e. is a QoS-data or
              * QoS-nulldata frame) then just set the EOSP bit there
              * and be done.
              * If the frame doesn't have a QoS header (which means
              * it should be a bufferable MMPDU) then we can't set
              * the EOSP bit in the QoS header; add a QoS-nulldata
              * frame to the list to send it after the MMPDU.
              *
              * Note that this code is only in the mac80211-release
              * code path, we assume that the driver will not buffer
              * anything but QoS-data frames, or if it does, will
              * create the QoS-nulldata frame by itself if needed.
              *
              * Cf. 802.11-2012 10.2.1.10 (c).
              */
             if (qoshdr) {
                 *qoshdr |= IEEE80211_QOS_CTL_EOSP;
 
                 info->flags |= IEEE80211_TX_STATUS_EOSP |
                            IEEE80211_TX_CTL_REQ_TX_STATUS;
             } else {
                 /* The standard isn't completely clear on this
                  * as it says the more-data bit should be set
                  * if there are more BUs. The QoS-Null frame
                  * we're about to send isn't buffered yet, we
                  * only create it below, but let's pretend it
                  * was buffered just in case some clients only
                  * expect more-data=0 when eosp=1.
                  */
                 hdr->frame_control |=
                     cpu_to_le16(IEEE80211_FCTL_MOREDATA);
                 need_null = true;
                 num++;
             }
             break;
         }
 
         drv_allow_buffered_frames(local, sta, tids, num,
                       reason, more_data);
 
         ieee80211_add_pending_skbs(local, &pending);
 
         if (need_null)
             ieee80211_send_null_response(
                 sta, find_highest_prio_tid(tids),
                 reason, false, false);
 
         sta_info_recalc_tim(sta);
     } else {
         int tid;
 
         /*
          * We need to release a frame that is buffered somewhere in the
          * driver ... it'll have to handle that.
          * Note that the driver also has to check the number of frames
          * on the TIDs we're releasing from - if there are more than
          * n_frames it has to set the more-data bit (if we didn't ask
          * it to set it anyway due to other buffered frames); if there
          * are fewer than n_frames it has to make sure to adjust that
          * to allow the service period to end properly.
          */
         drv_release_buffered_frames(local, sta, driver_release_tids,
                         n_frames, reason, more_data);
 
         /*
          * Note that we don't recalculate the TIM bit here as it would
          * most likely have no effect at all unless the driver told us
          * that the TID(s) became empty before returning here from the
          * release function.
          * Either way, however, when the driver tells us that the TID(s)
          * became empty or we find that a txq became empty, we'll do the
          * TIM recalculation.
          */
 
         if (!sta->sta.txq[0])
             return;
 
         for (tid = 0; tid < ARRAY_SIZE(sta->sta.txq); tid++) {
             if (!sta->sta.txq[tid] ||
                 !(driver_release_tids & BIT(tid)) ||
                 txq_has_queue(sta->sta.txq[tid]))
                 continue;
 
             sta_info_recalc_tim(sta);
             break;
         }
     }
 }
 
 void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta)
 {
     u8 ignore_for_response = sta->sta.uapsd_queues;
 
     /*
      * If all ACs are delivery-enabled then we should reply
      * from any of them, if only some are enabled we reply
      * only from the non-enabled ones.
      */
     if (ignore_for_response == BIT(IEEE80211_NUM_ACS) - 1)
         ignore_for_response = 0;
 
     ieee80211_sta_ps_deliver_response(sta, 1, ignore_for_response,
                       IEEE80211_FRAME_RELEASE_PSPOLL);
 }
 
 void ieee80211_sta_ps_deliver_uapsd(struct sta_info *sta)
 {
     int n_frames = sta->sta.max_sp;
     u8 delivery_enabled = sta->sta.uapsd_queues;
 
     /*
      * If we ever grow support for TSPEC this might happen if
      * the TSPEC update from hostapd comes in between a trigger
      * frame setting WLAN_STA_UAPSD in the RX path and this
      * actually getting called.
      */
     if (!delivery_enabled)
         return;
 
     switch (sta->sta.max_sp) {
     case 1:
         n_frames = 2;
         break;
     case 2:
         n_frames = 4;
         break;
     case 3:
         n_frames = 6;
         break;
     case 0:
         /* XXX: what is a good value? */
         n_frames = 128;
         break;
     }
 
     ieee80211_sta_ps_deliver_response(sta, n_frames, ~delivery_enabled,
                       IEEE80211_FRAME_RELEASE_UAPSD);
 }
 
 void ieee80211_sta_block_awake(struct ieee80211_hw *hw,
                    struct ieee80211_sta *pubsta, bool block)
 {
     struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 
     trace_api_sta_block_awake(sta->local, pubsta, block);
 
     if (block) {
         set_sta_flag(sta, WLAN_STA_PS_DRIVER);
         ieee80211_clear_fast_xmit(sta);
         return;
     }
 
     if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
         return;
 
     if (!test_sta_flag(sta, WLAN_STA_PS_STA)) {
         set_sta_flag(sta, WLAN_STA_PS_DELIVER);
         clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
         ieee80211_queue_work(hw, &sta->drv_deliver_wk);
     } else if (test_sta_flag(sta, WLAN_STA_PSPOLL) ||
            test_sta_flag(sta, WLAN_STA_UAPSD)) {
         /* must be asleep in this case */
         clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
         ieee80211_queue_work(hw, &sta->drv_deliver_wk);
     } else {
         clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
         ieee80211_check_fast_xmit(sta);
     }
 }
 EXPORT_SYMBOL(ieee80211_sta_block_awake);
 
 void ieee80211_sta_eosp(struct ieee80211_sta *pubsta)
 {
     struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
     struct ieee80211_local *local = sta->local;
 
     trace_api_eosp(local, pubsta);
 
     clear_sta_flag(sta, WLAN_STA_SP);
 }
 EXPORT_SYMBOL(ieee80211_sta_eosp);
 
 void ieee80211_send_eosp_nullfunc(struct ieee80211_sta *pubsta, int tid)
 {
     struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
     enum ieee80211_frame_release_type reason;
     bool more_data;
 
     trace_api_send_eosp_nullfunc(sta->local, pubsta, tid);
 
     reason = IEEE80211_FRAME_RELEASE_UAPSD;
     more_data = ieee80211_sta_ps_more_data(sta, ~sta->sta.uapsd_queues,
                            reason, 0);
 
     ieee80211_send_null_response(sta, tid, reason, false, more_data);
 }
 EXPORT_SYMBOL(ieee80211_send_eosp_nullfunc);
 
 void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta,
                 u8 tid, bool buffered)
 {
     struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 
     if (WARN_ON(tid >= IEEE80211_NUM_TIDS))
         return;
 
     trace_api_sta_set_buffered(sta->local, pubsta, tid, buffered);
 
     if (buffered)
         set_bit(tid, &sta->driver_buffered_tids);
     else
         clear_bit(tid, &sta->driver_buffered_tids);
 
     sta_info_recalc_tim(sta);
 }
 EXPORT_SYMBOL(ieee80211_sta_set_buffered);
 
 void ieee80211_sta_register_airtime(struct ieee80211_sta *pubsta, u8 tid,
                     u32 tx_airtime, u32 rx_airtime)
 {
     struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
     struct ieee80211_local *local = sta->sdata->local;
     u8 ac = ieee80211_ac_from_tid(tid);
     u32 airtime = 0;
     u32 diff;
 
     if (sta->local->airtime_flags & AIRTIME_USE_TX)
         airtime += tx_airtime;
     if (sta->local->airtime_flags & AIRTIME_USE_RX)
         airtime += rx_airtime;
 
     spin_lock_bh(&local->active_txq_lock[ac]);
     sta->airtime[ac].tx_airtime += tx_airtime;
     sta->airtime[ac].rx_airtime += rx_airtime;
 
     diff = (u32)jiffies - sta->airtime[ac].last_active;
     if (diff <= AIRTIME_ACTIVE_DURATION)
         sta->airtime[ac].deficit -= airtime;
 
     spin_unlock_bh(&local->active_txq_lock[ac]);
 }
 EXPORT_SYMBOL(ieee80211_sta_register_airtime);
 
 void ieee80211_sta_update_pending_airtime(struct ieee80211_local *local,
                       struct sta_info *sta, u8 ac,
                       u16 tx_airtime, bool tx_completed)
 {
     int tx_pending;
 
     if (!wiphy_ext_feature_isset(local->hw.wiphy, NL80211_EXT_FEATURE_AQL))
         return;
 
     if (!tx_completed) {
         if (sta)
             atomic_add(tx_airtime,
                    &sta->airtime[ac].aql_tx_pending);
 
         atomic_add(tx_airtime, &local->aql_total_pending_airtime);
         atomic_add(tx_airtime, &local->aql_ac_pending_airtime[ac]);
         return;
     }
 
     if (sta) {
         tx_pending = atomic_sub_return(tx_airtime,
                            &sta->airtime[ac].aql_tx_pending);
         if (tx_pending < 0)
             atomic_cmpxchg(&sta->airtime[ac].aql_tx_pending,
                        tx_pending, 0);
     }
 
     atomic_sub(tx_airtime, &local->aql_total_pending_airtime);
     tx_pending = atomic_sub_return(tx_airtime,
                        &local->aql_ac_pending_airtime[ac]);
     if (WARN_ONCE(tx_pending < 0,
               "Device %s AC %d pending airtime underflow: %u, %u",
               wiphy_name(local->hw.wiphy), ac, tx_pending,
               tx_airtime)) {
         atomic_cmpxchg(&local->aql_ac_pending_airtime[ac],
                    tx_pending, 0);
         atomic_sub(tx_pending, &local->aql_total_pending_airtime);
     }
 }
 
 int sta_info_move_state(struct sta_info *sta,
             enum ieee80211_sta_state new_state)
 {
     might_sleep();
 
     if (sta->sta_state == new_state)
         return 0;
 
     /* check allowed transitions first */
 
     switch (new_state) {
     case IEEE80211_STA_NONE:
         if (sta->sta_state != IEEE80211_STA_AUTH)
             return -EINVAL;
         break;
     case IEEE80211_STA_AUTH:
         if (sta->sta_state != IEEE80211_STA_NONE &&
             sta->sta_state != IEEE80211_STA_ASSOC)
             return -EINVAL;
         break;
     case IEEE80211_STA_ASSOC:
         if (sta->sta_state != IEEE80211_STA_AUTH &&
             sta->sta_state != IEEE80211_STA_AUTHORIZED)
             return -EINVAL;
         break;
     case IEEE80211_STA_AUTHORIZED:
         if (sta->sta_state != IEEE80211_STA_ASSOC)
             return -EINVAL;
         break;
     default:
         WARN(1, "invalid state %d", new_state);
         return -EINVAL;
     }
 
     sta_dbg(sta->sdata, "moving STA %pM to state %d\n",
         sta->sta.addr, new_state);
 
     /*
      * notify the driver before the actual changes so it can
      * fail the transition
      */
     if (test_sta_flag(sta, WLAN_STA_INSERTED)) {
         int err = drv_sta_state(sta->local, sta->sdata, sta,
                     sta->sta_state, new_state);
         if (err)
             return err;
     }
 
     /* reflect the change in all state variables */
 
     switch (new_state) {
     case IEEE80211_STA_NONE:
         if (sta->sta_state == IEEE80211_STA_AUTH)
             clear_bit(WLAN_STA_AUTH, &sta->_flags);
         break;
     case IEEE80211_STA_AUTH:
         if (sta->sta_state == IEEE80211_STA_NONE) {
             set_bit(WLAN_STA_AUTH, &sta->_flags);
         } else if (sta->sta_state == IEEE80211_STA_ASSOC) {
             clear_bit(WLAN_STA_ASSOC, &sta->_flags);
             ieee80211_recalc_min_chandef(sta->sdata, -1);
             if (!sta->sta.support_p2p_ps)
                 ieee80211_recalc_p2p_go_ps_allowed(sta->sdata);
         }
         break;
     case IEEE80211_STA_ASSOC:
         if (sta->sta_state == IEEE80211_STA_AUTH) {
             set_bit(WLAN_STA_ASSOC, &sta->_flags);
             sta->assoc_at = ktime_get_boottime_ns();
             ieee80211_recalc_min_chandef(sta->sdata, -1);
             if (!sta->sta.support_p2p_ps)
                 ieee80211_recalc_p2p_go_ps_allowed(sta->sdata);
         } else if (sta->sta_state == IEEE80211_STA_AUTHORIZED) {
             ieee80211_vif_dec_num_mcast(sta->sdata);
             clear_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
             ieee80211_clear_fast_xmit(sta);
             ieee80211_clear_fast_rx(sta);
         }
         break;
     case IEEE80211_STA_AUTHORIZED:
         if (sta->sta_state == IEEE80211_STA_ASSOC) {
             ieee80211_vif_inc_num_mcast(sta->sdata);
             set_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
             ieee80211_check_fast_xmit(sta);
             ieee80211_check_fast_rx(sta);
         }
         if (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
             sta->sdata->vif.type == NL80211_IFTYPE_AP)
             cfg80211_send_layer2_update(sta->sdata->dev,
                             sta->sta.addr);
         break;
     default:
         break;
     }
 
     sta->sta_state = new_state;
 
     return 0;
 }
 
 static struct ieee80211_sta_rx_stats *
 sta_get_last_rx_stats(struct sta_info *sta)
 {
     struct ieee80211_sta_rx_stats *stats = &sta->deflink.rx_stats;
     int cpu;
 
     if (!sta->deflink.pcpu_rx_stats)
         return stats;
 
     for_each_possible_cpu(cpu) {
         struct ieee80211_sta_rx_stats *cpustats;
 
         cpustats = per_cpu_ptr(sta->deflink.pcpu_rx_stats, cpu);
 
         if (time_after(cpustats->last_rx, stats->last_rx))
             stats = cpustats;
     }
 
     return stats;
 }
 
 static void sta_stats_decode_rate(struct ieee80211_local *local, u32 rate,
                   struct rate_info *rinfo)
 {
     rinfo->bw = STA_STATS_GET(BW, rate);
 
     switch (STA_STATS_GET(TYPE, rate)) {
     case STA_STATS_RATE_TYPE_VHT:
         rinfo->flags = RATE_INFO_FLAGS_VHT_MCS;
         rinfo->mcs = STA_STATS_GET(VHT_MCS, rate);
         rinfo->nss = STA_STATS_GET(VHT_NSS, rate);
         if (STA_STATS_GET(SGI, rate))
             rinfo->flags |= RATE_INFO_FLAGS_SHORT_GI;
         break;
     case STA_STATS_RATE_TYPE_HT:
         rinfo->flags = RATE_INFO_FLAGS_MCS;
         rinfo->mcs = STA_STATS_GET(HT_MCS, rate);
         if (STA_STATS_GET(SGI, rate))
             rinfo->flags |= RATE_INFO_FLAGS_SHORT_GI;
         break;
     case STA_STATS_RATE_TYPE_LEGACY: {
         struct ieee80211_supported_band *sband;
         u16 brate;
         unsigned int shift;
         int band = STA_STATS_GET(LEGACY_BAND, rate);
         int rate_idx = STA_STATS_GET(LEGACY_IDX, rate);
 
         sband = local->hw.wiphy->bands[band];
 
         if (WARN_ON_ONCE(!sband->bitrates))
             break;
 
         brate = sband->bitrates[rate_idx].bitrate;
         if (rinfo->bw == RATE_INFO_BW_5)
             shift = 2;
         else if (rinfo->bw == RATE_INFO_BW_10)
             shift = 1;
         else
             shift = 0;
         rinfo->legacy = DIV_ROUND_UP(brate, 1 << shift);
         break;
         }
     case STA_STATS_RATE_TYPE_HE:
         rinfo->flags = RATE_INFO_FLAGS_HE_MCS;
         rinfo->mcs = STA_STATS_GET(HE_MCS, rate);
         rinfo->nss = STA_STATS_GET(HE_NSS, rate);
         rinfo->he_gi = STA_STATS_GET(HE_GI, rate);
         rinfo->he_ru_alloc = STA_STATS_GET(HE_RU, rate);
         rinfo->he_dcm = STA_STATS_GET(HE_DCM, rate);
         break;
     }
 }
 
 static int sta_set_rate_info_rx(struct sta_info *sta, struct rate_info *rinfo)
 {
     u16 rate = READ_ONCE(sta_get_last_rx_stats(sta)->last_rate);
 
     if (rate == STA_STATS_RATE_INVALID)
         return -EINVAL;
 
     sta_stats_decode_rate(sta->local, rate, rinfo);
     return 0;
 }
 
 static inline u64 sta_get_tidstats_msdu(struct ieee80211_sta_rx_stats *rxstats,
                     int tid)
 {
     unsigned int start;
     u64 value;
 
     do {
         start = u64_stats_fetch_begin_irq(&rxstats->syncp);
         value = rxstats->msdu[tid];
     } while (u64_stats_fetch_retry_irq(&rxstats->syncp, start));
 
     return value;
 }
 
 static void sta_set_tidstats(struct sta_info *sta,
                  struct cfg80211_tid_stats *tidstats,
                  int tid)
 {
     struct ieee80211_local *local = sta->local;
     int cpu;
 
     if (!(tidstats->filled & BIT(NL80211_TID_STATS_RX_MSDU))) {
         tidstats->rx_msdu += sta_get_tidstats_msdu(&sta->deflink.rx_stats,
                                tid);
 
         if (sta->deflink.pcpu_rx_stats) {
             for_each_possible_cpu(cpu) {
                 struct ieee80211_sta_rx_stats *cpurxs;
 
                 cpurxs = per_cpu_ptr(sta->deflink.pcpu_rx_stats,
                              cpu);
                 tidstats->rx_msdu +=
                     sta_get_tidstats_msdu(cpurxs, tid);
             }
         }
 
         tidstats->filled |= BIT(NL80211_TID_STATS_RX_MSDU);
     }
 
     if (!(tidstats->filled & BIT(NL80211_TID_STATS_TX_MSDU))) {
         tidstats->filled |= BIT(NL80211_TID_STATS_TX_MSDU);
         tidstats->tx_msdu = sta->deflink.tx_stats.msdu[tid];
     }
 
     if (!(tidstats->filled & BIT(NL80211_TID_STATS_TX_MSDU_RETRIES)) &&
         ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
         tidstats->filled |= BIT(NL80211_TID_STATS_TX_MSDU_RETRIES);
         tidstats->tx_msdu_retries = sta->deflink.status_stats.msdu_retries[tid];
     }
 
     if (!(tidstats->filled & BIT(NL80211_TID_STATS_TX_MSDU_FAILED)) &&
         ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
         tidstats->filled |= BIT(NL80211_TID_STATS_TX_MSDU_FAILED);
         tidstats->tx_msdu_failed = sta->deflink.status_stats.msdu_failed[tid];
     }
 
     if (local->ops->wake_tx_queue && tid < IEEE80211_NUM_TIDS) {
         spin_lock_bh(&local->fq.lock);
         rcu_read_lock();
 
         tidstats->filled |= BIT(NL80211_TID_STATS_TXQ_STATS);
         ieee80211_fill_txq_stats(&tidstats->txq_stats,
                      to_txq_info(sta->sta.txq[tid]));
 
         rcu_read_unlock();
         spin_unlock_bh(&local->fq.lock);
     }
 }
 
 static inline u64 sta_get_stats_bytes(struct ieee80211_sta_rx_stats *rxstats)
 {
     unsigned int start;
     u64 value;
 
     do {
         start = u64_stats_fetch_begin_irq(&rxstats->syncp);
         value = rxstats->bytes;
     } while (u64_stats_fetch_retry_irq(&rxstats->syncp, start));
 
     return value;
 }
 
 void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo,
            bool tidstats)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct ieee80211_local *local = sdata->local;
     u32 thr = 0;
     int i, ac, cpu;
     struct ieee80211_sta_rx_stats *last_rxstats;
 
     last_rxstats = sta_get_last_rx_stats(sta);
 
     sinfo->generation = sdata->local->sta_generation;
 
     /* do before driver, so beacon filtering drivers have a
      * chance to e.g. just add the number of filtered beacons
      * (or just modify the value entirely, of course)
      */
     if (sdata->vif.type == NL80211_IFTYPE_STATION)
         sinfo->rx_beacon = sdata->deflink.u.mgd.count_beacon_signal;
 
     drv_sta_statistics(local, sdata, &sta->sta, sinfo);
     sinfo->filled |= BIT_ULL(NL80211_STA_INFO_INACTIVE_TIME) |
              BIT_ULL(NL80211_STA_INFO_STA_FLAGS) |
              BIT_ULL(NL80211_STA_INFO_BSS_PARAM) |
              BIT_ULL(NL80211_STA_INFO_CONNECTED_TIME) |
              BIT_ULL(NL80211_STA_INFO_ASSOC_AT_BOOTTIME) |
              BIT_ULL(NL80211_STA_INFO_RX_DROP_MISC);
 
     if (sdata->vif.type == NL80211_IFTYPE_STATION) {
         sinfo->beacon_loss_count =
             sdata->deflink.u.mgd.beacon_loss_count;
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_BEACON_LOSS);
     }
 
     sinfo->connected_time = ktime_get_seconds() - sta->last_connected;
     sinfo->assoc_at = sta->assoc_at;
     sinfo->inactive_time =
         jiffies_to_msecs(jiffies - ieee80211_sta_last_active(sta));
 
     if (!(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_TX_BYTES64) |
                    BIT_ULL(NL80211_STA_INFO_TX_BYTES)))) {
         sinfo->tx_bytes = 0;
         for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
             sinfo->tx_bytes += sta->deflink.tx_stats.bytes[ac];
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_BYTES64);
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_PACKETS))) {
         sinfo->tx_packets = 0;
         for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
             sinfo->tx_packets += sta->deflink.tx_stats.packets[ac];
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_PACKETS);
     }
 
     if (!(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_RX_BYTES64) |
                    BIT_ULL(NL80211_STA_INFO_RX_BYTES)))) {
         sinfo->rx_bytes += sta_get_stats_bytes(&sta->deflink.rx_stats);
 
         if (sta->deflink.pcpu_rx_stats) {
             for_each_possible_cpu(cpu) {
                 struct ieee80211_sta_rx_stats *cpurxs;
 
                 cpurxs = per_cpu_ptr(sta->deflink.pcpu_rx_stats,
                              cpu);
                 sinfo->rx_bytes += sta_get_stats_bytes(cpurxs);
             }
         }
 
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_BYTES64);
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_PACKETS))) {
         sinfo->rx_packets = sta->deflink.rx_stats.packets;
         if (sta->deflink.pcpu_rx_stats) {
             for_each_possible_cpu(cpu) {
                 struct ieee80211_sta_rx_stats *cpurxs;
 
                 cpurxs = per_cpu_ptr(sta->deflink.pcpu_rx_stats,
                              cpu);
                 sinfo->rx_packets += cpurxs->packets;
             }
         }
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_PACKETS);
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_RETRIES))) {
         sinfo->tx_retries = sta->deflink.status_stats.retry_count;
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_RETRIES);
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_FAILED))) {
         sinfo->tx_failed = sta->deflink.status_stats.retry_failed;
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_FAILED);
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_DURATION))) {
         for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
             sinfo->rx_duration += sta->airtime[ac].rx_airtime;
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_DURATION);
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_DURATION))) {
         for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
             sinfo->tx_duration += sta->airtime[ac].tx_airtime;
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_DURATION);
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT))) {
         sinfo->airtime_weight = sta->airtime_weight;
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT);
     }
 
     sinfo->rx_dropped_misc = sta->deflink.rx_stats.dropped;
     if (sta->deflink.pcpu_rx_stats) {
         for_each_possible_cpu(cpu) {
             struct ieee80211_sta_rx_stats *cpurxs;
 
             cpurxs = per_cpu_ptr(sta->deflink.pcpu_rx_stats, cpu);
             sinfo->rx_dropped_misc += cpurxs->dropped;
         }
     }
 
     if (sdata->vif.type == NL80211_IFTYPE_STATION &&
         !(sdata->vif.driver_flags & IEEE80211_VIF_BEACON_FILTER)) {
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_BEACON_RX) |
                  BIT_ULL(NL80211_STA_INFO_BEACON_SIGNAL_AVG);
         sinfo->rx_beacon_signal_avg = ieee80211_ave_rssi(&sdata->vif);
     }
 
     if (ieee80211_hw_check(&sta->local->hw, SIGNAL_DBM) ||
         ieee80211_hw_check(&sta->local->hw, SIGNAL_UNSPEC)) {
         if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_SIGNAL))) {
             sinfo->signal = (s8)last_rxstats->last_signal;
             sinfo->filled |= BIT_ULL(NL80211_STA_INFO_SIGNAL);
         }
 
         if (!sta->deflink.pcpu_rx_stats &&
             !(sinfo->filled & BIT_ULL(NL80211_STA_INFO_SIGNAL_AVG))) {
             sinfo->signal_avg =
                 -ewma_signal_read(&sta->deflink.rx_stats_avg.signal);
             sinfo->filled |= BIT_ULL(NL80211_STA_INFO_SIGNAL_AVG);
         }
     }
 
     /* for the average - if pcpu_rx_stats isn't set - rxstats must point to
      * the sta->rx_stats struct, so the check here is fine with and without
      * pcpu statistics
      */
     if (last_rxstats->chains &&
         !(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL) |
                    BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL_AVG)))) {
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL);
         if (!sta->deflink.pcpu_rx_stats)
             sinfo->filled |= BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL_AVG);
 
         sinfo->chains = last_rxstats->chains;
 
         for (i = 0; i < ARRAY_SIZE(sinfo->chain_signal); i++) {
             sinfo->chain_signal[i] =
                 last_rxstats->chain_signal_last[i];
             sinfo->chain_signal_avg[i] =
                 -ewma_signal_read(&sta->deflink.rx_stats_avg.chain_signal[i]);
         }
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_BITRATE)) &&
         !sta->sta.valid_links) {
         sta_set_rate_info_tx(sta, &sta->deflink.tx_stats.last_rate,
                      &sinfo->txrate);
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_BITRATE);
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_BITRATE)) &&
         !sta->sta.valid_links) {
         if (sta_set_rate_info_rx(sta, &sinfo->rxrate) == 0)
             sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_BITRATE);
     }
 
     if (tidstats && !cfg80211_sinfo_alloc_tid_stats(sinfo, GFP_KERNEL)) {
         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
             sta_set_tidstats(sta, &sinfo->pertid[i], i);
     }
 
     if (ieee80211_vif_is_mesh(&sdata->vif)) {
 #ifdef CONFIG_MAC80211_MESH
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_LLID) |
                  BIT_ULL(NL80211_STA_INFO_PLID) |
                  BIT_ULL(NL80211_STA_INFO_PLINK_STATE) |
                  BIT_ULL(NL80211_STA_INFO_LOCAL_PM) |
                  BIT_ULL(NL80211_STA_INFO_PEER_PM) |
                  BIT_ULL(NL80211_STA_INFO_NONPEER_PM) |
                  BIT_ULL(NL80211_STA_INFO_CONNECTED_TO_GATE) |
                  BIT_ULL(NL80211_STA_INFO_CONNECTED_TO_AS);
 
         sinfo->llid = sta->mesh->llid;
         sinfo->plid = sta->mesh->plid;
         sinfo->plink_state = sta->mesh->plink_state;
         if (test_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN)) {
             sinfo->filled |= BIT_ULL(NL80211_STA_INFO_T_OFFSET);
             sinfo->t_offset = sta->mesh->t_offset;
         }
         sinfo->local_pm = sta->mesh->local_pm;
         sinfo->peer_pm = sta->mesh->peer_pm;
         sinfo->nonpeer_pm = sta->mesh->nonpeer_pm;
         sinfo->connected_to_gate = sta->mesh->connected_to_gate;
         sinfo->connected_to_as = sta->mesh->connected_to_as;
 #endif
     }
 
     sinfo->bss_param.flags = 0;
     if (sdata->vif.bss_conf.use_cts_prot)
         sinfo->bss_param.flags |= BSS_PARAM_FLAGS_CTS_PROT;
     if (sdata->vif.bss_conf.use_short_preamble)
         sinfo->bss_param.flags |= BSS_PARAM_FLAGS_SHORT_PREAMBLE;
     if (sdata->vif.bss_conf.use_short_slot)
         sinfo->bss_param.flags |= BSS_PARAM_FLAGS_SHORT_SLOT_TIME;
     sinfo->bss_param.dtim_period = sdata->vif.bss_conf.dtim_period;
     sinfo->bss_param.beacon_interval = sdata->vif.bss_conf.beacon_int;
 
     sinfo->sta_flags.set = 0;
     sinfo->sta_flags.mask = BIT(NL80211_STA_FLAG_AUTHORIZED) |
                 BIT(NL80211_STA_FLAG_SHORT_PREAMBLE) |
                 BIT(NL80211_STA_FLAG_WME) |
                 BIT(NL80211_STA_FLAG_MFP) |
                 BIT(NL80211_STA_FLAG_AUTHENTICATED) |
                 BIT(NL80211_STA_FLAG_ASSOCIATED) |
                 BIT(NL80211_STA_FLAG_TDLS_PEER);
     if (test_sta_flag(sta, WLAN_STA_AUTHORIZED))
         sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_AUTHORIZED);
     if (test_sta_flag(sta, WLAN_STA_SHORT_PREAMBLE))
         sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_SHORT_PREAMBLE);
     if (sta->sta.wme)
         sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_WME);
     if (test_sta_flag(sta, WLAN_STA_MFP))
         sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_MFP);
     if (test_sta_flag(sta, WLAN_STA_AUTH))
         sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_AUTHENTICATED);
     if (test_sta_flag(sta, WLAN_STA_ASSOC))
         sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_ASSOCIATED);
     if (test_sta_flag(sta, WLAN_STA_TDLS_PEER))
         sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_TDLS_PEER);
 
     thr = sta_get_expected_throughput(sta);
 
     if (thr != 0) {
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_EXPECTED_THROUGHPUT);
         sinfo->expected_throughput = thr;
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL)) &&
         sta->deflink.status_stats.ack_signal_filled) {
         sinfo->ack_signal = sta->deflink.status_stats.last_ack_signal;
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL);
     }
 
     if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL_AVG)) &&
         sta->deflink.status_stats.ack_signal_filled) {
         sinfo->avg_ack_signal =
             -(s8)ewma_avg_signal_read(
                 &sta->deflink.status_stats.avg_ack_signal);
         sinfo->filled |=
             BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL_AVG);
     }
 
     if (ieee80211_vif_is_mesh(&sdata->vif)) {
         sinfo->filled |= BIT_ULL(NL80211_STA_INFO_AIRTIME_LINK_METRIC);
         sinfo->airtime_link_metric =
             airtime_link_metric_get(local, sta);
     }
 }
 
 u32 sta_get_expected_throughput(struct sta_info *sta)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct ieee80211_local *local = sdata->local;
     struct rate_control_ref *ref = NULL;
     u32 thr = 0;
 
     if (test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
         ref = local->rate_ctrl;
 
     /* check if the driver has a SW RC implementation */
     if (ref && ref->ops->get_expected_throughput)
         thr = ref->ops->get_expected_throughput(sta->rate_ctrl_priv);
     else
         thr = drv_get_expected_throughput(local, sta);
 
     return thr;
 }
 
 unsigned long ieee80211_sta_last_active(struct sta_info *sta)
 {
     struct ieee80211_sta_rx_stats *stats = sta_get_last_rx_stats(sta);
 
     if (!sta->deflink.status_stats.last_ack ||
         time_after(stats->last_rx, sta->deflink.status_stats.last_ack))
         return stats->last_rx;
     return sta->deflink.status_stats.last_ack;
 }
 
 static void sta_update_codel_params(struct sta_info *sta, u32 thr)
 {
     if (!sta->sdata->local->ops->wake_tx_queue)
         return;
 
     if (thr && thr < STA_SLOW_THRESHOLD * sta->local->num_sta) {
         sta->cparams.target = MS2TIME(50);
         sta->cparams.interval = MS2TIME(300);
         sta->cparams.ecn = false;
     } else {
         sta->cparams.target = MS2TIME(20);
         sta->cparams.interval = MS2TIME(100);
         sta->cparams.ecn = true;
     }
 }
 
 void ieee80211_sta_set_expected_throughput(struct ieee80211_sta *pubsta,
                        u32 thr)
 {
     struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 
     sta_update_codel_params(sta, thr);
 }
 
 int ieee80211_sta_allocate_link(struct sta_info *sta, unsigned int link_id)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct sta_link_alloc *alloc;
     int ret;
 
     lockdep_assert_held(&sdata->local->sta_mtx);
 
     /* must represent an MLD from the start */
     if (WARN_ON(!sta->sta.valid_links))
         return -EINVAL;
 
     if (WARN_ON(sta->sta.valid_links & BIT(link_id) ||
             sta->link[link_id]))
         return -EBUSY;
 
     alloc = kzalloc(sizeof(*alloc), GFP_KERNEL);
     if (!alloc)
         return -ENOMEM;
 
     ret = sta_info_alloc_link(sdata->local, &alloc->info, GFP_KERNEL);
     if (ret) {
         kfree(alloc);
         return ret;
     }
 
     sta_info_add_link(sta, link_id, &alloc->info, &alloc->sta);
 
     return 0;
 }
 
 void ieee80211_sta_free_link(struct sta_info *sta, unsigned int link_id)
 {
     lockdep_assert_held(&sta->sdata->local->sta_mtx);
 
     sta_remove_link(sta, link_id, false);
 }
 
 int ieee80211_sta_activate_link(struct sta_info *sta, unsigned int link_id)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
     struct link_sta_info *link_sta;
     u16 old_links = sta->sta.valid_links;
     u16 new_links = old_links | BIT(link_id);
     int ret;
 
     link_sta = rcu_dereference_protected(sta->link[link_id],
                          lockdep_is_held(&sdata->local->sta_mtx));
 
     if (WARN_ON(old_links == new_links || !link_sta))
         return -EINVAL;
 
     rcu_read_lock();
     if (link_sta_info_hash_lookup(sdata->local, link_sta->addr)) {
         rcu_read_unlock();
         return -EALREADY;
     }
     /* we only modify under the mutex so this is fine */
     rcu_read_unlock();
 
     sta->sta.valid_links = new_links;
 
     if (!test_sta_flag(sta, WLAN_STA_INSERTED)) {
         ret = 0;
         goto hash;
     }
 
     ret = drv_change_sta_links(sdata->local, sdata, &sta->sta,
                    old_links, new_links);
     if (ret) {
         sta->sta.valid_links = old_links;
         sta_remove_link(sta, link_id, false);
         return ret;
     }
 
 hash:
     ret = link_sta_info_hash_add(sdata->local, link_sta);
     WARN_ON(ret);
     return 0;
 }
 
 void ieee80211_sta_remove_link(struct sta_info *sta, unsigned int link_id)
 {
     struct ieee80211_sub_if_data *sdata = sta->sdata;
 
     lockdep_assert_held(&sdata->local->sta_mtx);
 
     sta->sta.valid_links &= ~BIT(link_id);
 
     if (test_sta_flag(sta, WLAN_STA_INSERTED))
         drv_change_sta_links(sdata->local, sdata, &sta->sta,
                      sta->sta.valid_links,
                      sta->sta.valid_links & ~BIT(link_id));
 
     sta_remove_link(sta, link_id, true);
 }
 
 void ieee80211_sta_set_max_amsdu_subframes(struct sta_info *sta,
                        const u8 *ext_capab,
                        unsigned int ext_capab_len)
 {
     u8 val;
 
     sta->sta.max_amsdu_subframes = 0;
 
     if (ext_capab_len < 8)
         return;
 
     /* The sender might not have sent the last bit, consider it to be 0 */
     val = u8_get_bits(ext_capab[7], WLAN_EXT_CAPA8_MAX_MSDU_IN_AMSDU_LSB);
 
     /* we did get all the bits, take the MSB as well */
     if (ext_capab_len >= 9)
         val |= u8_get_bits(ext_capab[8],
                    WLAN_EXT_CAPA9_MAX_MSDU_IN_AMSDU_MSB) << 1;
 
     if (val)
         sta->sta.max_amsdu_subframes = 4 << val;
 }