/* * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2006-2007 Jiri Benc * * 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 #include #include #include #include #include #include #include #include #include #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. */ /* Caller must hold local->sta_lock */ static int sta_info_hash_del(struct ieee80211_local *local, struct sta_info *sta) { struct sta_info *s; s = rcu_dereference_protected(local->sta_hash[STA_HASH(sta->sta.addr)], lockdep_is_held(&local->sta_lock)); if (!s) return -ENOENT; if (s == sta) { rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], s->hnext); return 0; } while (rcu_access_pointer(s->hnext) && rcu_access_pointer(s->hnext) != sta) s = rcu_dereference_protected(s->hnext, lockdep_is_held(&local->sta_lock)); if (rcu_access_pointer(s->hnext)) { rcu_assign_pointer(s->hnext, sta->hnext); return 0; } return -ENOENT; } /* 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 sta_info *sta; sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], lockdep_is_held(&local->sta_lock) || lockdep_is_held(&local->sta_mtx)); while (sta) { if (sta->sdata == sdata && !sta->dummy && memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) break; sta = rcu_dereference_check(sta->hnext, lockdep_is_held(&local->sta_lock) || lockdep_is_held(&local->sta_mtx)); } return sta; } /* get a station info entry even if it is a dummy station*/ struct sta_info *sta_info_get_rx(struct ieee80211_sub_if_data *sdata, const u8 *addr) { struct ieee80211_local *local = sdata->local; struct sta_info *sta; sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], lockdep_is_held(&local->sta_lock) || lockdep_is_held(&local->sta_mtx)); while (sta) { if (sta->sdata == sdata && memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) break; sta = rcu_dereference_check(sta->hnext, lockdep_is_held(&local->sta_lock) || lockdep_is_held(&local->sta_mtx)); } return sta; } /* * 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 sta_info *sta; sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], lockdep_is_held(&local->sta_lock) || lockdep_is_held(&local->sta_mtx)); while (sta) { if ((sta->sdata == sdata || (sta->sdata->bss && sta->sdata->bss == sdata->bss)) && !sta->dummy && memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) break; sta = rcu_dereference_check(sta->hnext, lockdep_is_held(&local->sta_lock) || lockdep_is_held(&local->sta_mtx)); } return sta; } /* * Get sta info either from the specified interface * or from one of its vlans (including dummy stations) */ struct sta_info *sta_info_get_bss_rx(struct ieee80211_sub_if_data *sdata, const u8 *addr) { struct ieee80211_local *local = sdata->local; struct sta_info *sta; sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], lockdep_is_held(&local->sta_lock) || lockdep_is_held(&local->sta_mtx)); while (sta) { if ((sta->sdata == sdata || (sta->sdata->bss && sta->sdata->bss == sdata->bss)) && memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) break; sta = rcu_dereference_check(sta->hnext, lockdep_is_held(&local->sta_lock) || lockdep_is_held(&local->sta_mtx)); } return sta; } 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) { if (sdata != sta->sdata) continue; if (i < idx) { ++i; continue; } return sta; } return NULL; } /** * __sta_info_free - internal STA free helper * * @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(). */ static void __sta_info_free(struct ieee80211_local *local, struct sta_info *sta) { if (sta->rate_ctrl) { rate_control_free_sta(sta); rate_control_put(sta->rate_ctrl); } #ifdef CONFIG_MAC80211_VERBOSE_DEBUG wiphy_debug(local->hw.wiphy, "Destroyed STA %pM\n", sta->sta.addr); #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ kfree(sta); } /* Caller must hold local->sta_lock */ static void sta_info_hash_add(struct ieee80211_local *local, struct sta_info *sta) { sta->hnext = local->sta_hash[STA_HASH(sta->sta.addr)]; rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], sta); } static void sta_unblock(struct work_struct *wk) { struct sta_info *sta; sta = container_of(wk, struct sta_info, drv_unblock_wk); if (sta->dead) return; 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)) { clear_sta_flag(sta, WLAN_STA_PS_DRIVER); local_bh_disable(); ieee80211_sta_ps_deliver_poll_response(sta); local_bh_enable(); } else if (test_and_clear_sta_flag(sta, WLAN_STA_UAPSD)) { clear_sta_flag(sta, WLAN_STA_PS_DRIVER); local_bh_disable(); ieee80211_sta_ps_deliver_uapsd(sta); local_bh_enable(); } else clear_sta_flag(sta, WLAN_STA_PS_DRIVER); } static int sta_prepare_rate_control(struct ieee80211_local *local, struct sta_info *sta, gfp_t gfp) { if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) return 0; sta->rate_ctrl = rate_control_get(local->rate_ctrl); sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, &sta->sta, gfp); if (!sta->rate_ctrl_priv) { rate_control_put(sta->rate_ctrl); return -ENOMEM; } return 0; } struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr, gfp_t gfp) { struct ieee80211_local *local = sdata->local; struct sta_info *sta; struct timespec uptime; int i; sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp); if (!sta) return NULL; spin_lock_init(&sta->lock); INIT_WORK(&sta->drv_unblock_wk, sta_unblock); INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work); mutex_init(&sta->ampdu_mlme.mtx); memcpy(sta->sta.addr, addr, ETH_ALEN); sta->local = local; sta->sdata = sdata; sta->last_rx = jiffies; do_posix_clock_monotonic_gettime(&uptime); sta->last_connected = uptime.tv_sec; ewma_init(&sta->avg_signal, 1024, 8); if (sta_prepare_rate_control(local, sta, gfp)) { kfree(sta); return NULL; } for (i = 0; i < STA_TID_NUM; i++) { /* * timer_to_tid must be initialized with identity mapping * to enable session_timer's data differentiation. See * sta_rx_agg_session_timer_expired for usage. */ sta->timer_to_tid[i] = i; } 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]); } for (i = 0; i < NUM_RX_DATA_QUEUES; i++) sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX); #ifdef CONFIG_MAC80211_VERBOSE_DEBUG wiphy_debug(local->hw.wiphy, "Allocated STA %pM\n", sta->sta.addr); #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ #ifdef CONFIG_MAC80211_MESH sta->plink_state = NL80211_PLINK_LISTEN; init_timer(&sta->plink_timer); #endif return sta; } static int sta_info_finish_insert(struct sta_info *sta, bool async, bool dummy_reinsert) { struct ieee80211_local *local = sta->local; struct ieee80211_sub_if_data *sdata = sta->sdata; struct station_info sinfo; unsigned long flags; int err = 0; lockdep_assert_held(&local->sta_mtx); if (!sta->dummy || dummy_reinsert) { /* notify driver */ if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) sdata = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap); err = drv_sta_add(local, sdata, &sta->sta); if (err) { if (!async) return err; printk(KERN_DEBUG "%s: failed to add IBSS STA %pM to " "driver (%d) - keeping it anyway.\n", sdata->name, sta->sta.addr, err); } else { sta->uploaded = true; #ifdef CONFIG_MAC80211_VERBOSE_DEBUG if (async) wiphy_debug(local->hw.wiphy, "Finished adding IBSS STA %pM\n", sta->sta.addr); #endif } sdata = sta->sdata; } if (!dummy_reinsert) { if (!async) { local->num_sta++; local->sta_generation++; smp_mb(); /* make the station visible */ spin_lock_irqsave(&local->sta_lock, flags); sta_info_hash_add(local, sta); spin_unlock_irqrestore(&local->sta_lock, flags); } list_add(&sta->list, &local->sta_list); } else { sta->dummy = false; } if (!sta->dummy) { ieee80211_sta_debugfs_add(sta); rate_control_add_sta_debugfs(sta); memset(&sinfo, 0, sizeof(sinfo)); sinfo.filled = 0; sinfo.generation = local->sta_generation; cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL); } return 0; } static void sta_info_finish_pending(struct ieee80211_local *local) { struct sta_info *sta; unsigned long flags; spin_lock_irqsave(&local->sta_lock, flags); while (!list_empty(&local->sta_pending_list)) { sta = list_first_entry(&local->sta_pending_list, struct sta_info, list); list_del(&sta->list); spin_unlock_irqrestore(&local->sta_lock, flags); sta_info_finish_insert(sta, true, false); spin_lock_irqsave(&local->sta_lock, flags); } spin_unlock_irqrestore(&local->sta_lock, flags); } static void sta_info_finish_work(struct work_struct *work) { struct ieee80211_local *local = container_of(work, struct ieee80211_local, sta_finish_work); mutex_lock(&local->sta_mtx); sta_info_finish_pending(local); mutex_unlock(&local->sta_mtx); } 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(compare_ether_addr(sta->sta.addr, sdata->vif.addr) == 0 || is_multicast_ether_addr(sta->sta.addr))) return -EINVAL; return 0; } static int sta_info_insert_ibss(struct sta_info *sta) __acquires(RCU) { struct ieee80211_local *local = sta->local; struct ieee80211_sub_if_data *sdata = sta->sdata; unsigned long flags; spin_lock_irqsave(&local->sta_lock, flags); /* check if STA exists already */ if (sta_info_get_bss_rx(sdata, sta->sta.addr)) { spin_unlock_irqrestore(&local->sta_lock, flags); rcu_read_lock(); return -EEXIST; } local->num_sta++; local->sta_generation++; smp_mb(); sta_info_hash_add(local, sta); list_add_tail(&sta->list, &local->sta_pending_list); rcu_read_lock(); spin_unlock_irqrestore(&local->sta_lock, flags); #ifdef CONFIG_MAC80211_VERBOSE_DEBUG wiphy_debug(local->hw.wiphy, "Added IBSS STA %pM\n", sta->sta.addr); #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ ieee80211_queue_work(&local->hw, &local->sta_finish_work); return 0; } /* * should be called with sta_mtx locked * this function replaces the mutex lock * with a RCU lock */ static int sta_info_insert_non_ibss(struct sta_info *sta) __acquires(RCU) { struct ieee80211_local *local = sta->local; struct ieee80211_sub_if_data *sdata = sta->sdata; unsigned long flags; struct sta_info *exist_sta; bool dummy_reinsert = false; int err = 0; lockdep_assert_held(&local->sta_mtx); /* * On first glance, this will look racy, because the code * in this function, which inserts a station with sleeping, * unlocks the sta_lock between checking existence in the * hash table and inserting into it. * * However, it is not racy against itself because it keeps * the mutex locked. */ spin_lock_irqsave(&local->sta_lock, flags); /* * check if STA exists already. * only accept a scenario of a second call to sta_info_insert_non_ibss * with a dummy station entry that was inserted earlier * in that case - assume that the dummy station flag should * be removed. */ exist_sta = sta_info_get_bss_rx(sdata, sta->sta.addr); if (exist_sta) { if (exist_sta == sta && sta->dummy) { dummy_reinsert = true; } else { spin_unlock_irqrestore(&local->sta_lock, flags); mutex_unlock(&local->sta_mtx); rcu_read_lock(); return -EEXIST; } } spin_unlock_irqrestore(&local->sta_lock, flags); err = sta_info_finish_insert(sta, false, dummy_reinsert); if (err) { mutex_unlock(&local->sta_mtx); rcu_read_lock(); return err; } #ifdef CONFIG_MAC80211_VERBOSE_DEBUG wiphy_debug(local->hw.wiphy, "Inserted %sSTA %pM\n", sta->dummy ? "dummy " : "", sta->sta.addr); #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ /* 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; } int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU) { struct ieee80211_local *local = sta->local; struct ieee80211_sub_if_data *sdata = sta->sdata; int err = 0; err = sta_info_insert_check(sta); if (err) { rcu_read_lock(); goto out_free; } /* * In ad-hoc mode, we sometimes need to insert stations * from tasklet context from the RX path. To avoid races, * always do so in that case -- see the comment below. */ if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { err = sta_info_insert_ibss(sta); if (err) goto out_free; return 0; } /* * It might seem that the function called below is in race against * the function call above that atomically inserts the station... That, * however, is not true because the above code can only * be invoked for IBSS interfaces, and the below code will * not be -- and the two do not race against each other as * the hash table also keys off the interface. */ might_sleep(); mutex_lock(&local->sta_mtx); err = sta_info_insert_non_ibss(sta); if (err) goto out_free; return 0; out_free: BUG_ON(!err); __sta_info_free(local, sta); return err; } int sta_info_insert(struct sta_info *sta) { int err = sta_info_insert_rcu(sta); rcu_read_unlock(); return err; } /* Caller must hold sta->local->sta_mtx */ int sta_info_reinsert(struct sta_info *sta) { struct ieee80211_local *local = sta->local; int err = 0; err = sta_info_insert_check(sta); if (err) { mutex_unlock(&local->sta_mtx); return err; } might_sleep(); err = sta_info_insert_non_ibss(sta); rcu_read_unlock(); return err; } static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid) { /* * This format has been mandated by the IEEE specifications, * so this line may not be changed to use the __set_bit() format. */ bss->tim[aid / 8] |= (1 << (aid % 8)); } static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid) { /* * This format has been mandated by the IEEE specifications, * so this line may not be changed to use the __clear_bit() format. */ bss->tim[aid / 8] &= ~(1 << (aid % 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; } } void sta_info_recalc_tim(struct sta_info *sta) { struct ieee80211_local *local = sta->local; struct ieee80211_if_ap *bss = sta->sdata->bss; unsigned long flags; bool indicate_tim = false; u8 ignore_for_tim = sta->sta.uapsd_queues; int ac; if (WARN_ON_ONCE(!sta->sdata->bss)) return; /* No need to do anything if the driver does all */ if (local->hw.flags & IEEE80211_HW_AP_LINK_PS) 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; for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) { unsigned long tids; if (ignore_for_tim & BIT(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; } done: spin_lock_irqsave(&local->sta_lock, flags); if (indicate_tim) __bss_tim_set(bss, sta->sta.aid); else __bss_tim_clear(bss, sta->sta.aid); if (local->ops->set_tim) { local->tim_in_locked_section = true; drv_set_tim(local, &sta->sta, indicate_tim); local->tim_in_locked_section = false; } spin_unlock_irqrestore(&local->sta_lock, flags); } 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; dev_kfree_skb(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--; #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n", sta->sta.addr); #endif dev_kfree_skb(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 interfaces */ if (!sta->sdata->bss) 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(struct sta_info *sta) { struct ieee80211_local *local; struct ieee80211_sub_if_data *sdata; unsigned long flags; int ret, i, ac; might_sleep(); if (!sta) return -ENOENT; local = sta->local; sdata = sta->sdata; /* * 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, true); spin_lock_irqsave(&local->sta_lock, flags); ret = sta_info_hash_del(local, sta); /* this might still be the pending list ... which is fine */ if (!ret) list_del(&sta->list); spin_unlock_irqrestore(&local->sta_lock, flags); if (ret) return ret; mutex_lock(&local->key_mtx); for (i = 0; i < NUM_DEFAULT_KEYS; i++) __ieee80211_key_free(key_mtx_dereference(local, sta->gtk[i])); if (sta->ptk) __ieee80211_key_free(key_mtx_dereference(local, sta->ptk)); mutex_unlock(&local->key_mtx); sta->dead = true; if (test_sta_flag(sta, WLAN_STA_PS_STA) || test_sta_flag(sta, WLAN_STA_PS_DRIVER)) { BUG_ON(!sdata->bss); clear_sta_flag(sta, WLAN_STA_PS_STA); clear_sta_flag(sta, WLAN_STA_PS_DRIVER); atomic_dec(&sdata->bss->num_sta_ps); sta_info_recalc_tim(sta); } local->num_sta--; local->sta_generation++; if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) rcu_assign_pointer(sdata->u.vlan.sta, NULL); if (sta->uploaded) { if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) sdata = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap); drv_sta_remove(local, sdata, &sta->sta); sdata = sta->sdata; } /* * At this point, after we wait for an RCU grace period, * neither mac80211 nor the driver can reference this * sta struct any more except by still existing timers * associated with this station that we clean up below. */ synchronize_rcu(); for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) { local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf[ac]); __skb_queue_purge(&sta->ps_tx_buf[ac]); __skb_queue_purge(&sta->tx_filtered[ac]); } #ifdef CONFIG_MAC80211_MESH if (ieee80211_vif_is_mesh(&sdata->vif)) mesh_accept_plinks_update(sdata); #endif #ifdef CONFIG_MAC80211_VERBOSE_DEBUG wiphy_debug(local->hw.wiphy, "Removed STA %pM\n", sta->sta.addr); #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ cancel_work_sync(&sta->drv_unblock_wk); cfg80211_del_sta(sdata->dev, sta->sta.addr, GFP_KERNEL); rate_control_remove_sta_debugfs(sta); ieee80211_sta_debugfs_remove(sta); #ifdef CONFIG_MAC80211_MESH if (ieee80211_vif_is_mesh(&sta->sdata->vif)) { mesh_plink_deactivate(sta); del_timer_sync(&sta->plink_timer); } #endif __sta_info_free(local, 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_rx(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_rx(sdata, addr); ret = __sta_info_destroy(sta); mutex_unlock(&sdata->local->sta_mtx); return ret; } static void sta_info_cleanup(unsigned long data) { struct ieee80211_local *local = (struct ieee80211_local *) data; 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)); } void sta_info_init(struct ieee80211_local *local) { spin_lock_init(&local->sta_lock); mutex_init(&local->sta_mtx); INIT_LIST_HEAD(&local->sta_list); INIT_LIST_HEAD(&local->sta_pending_list); INIT_WORK(&local->sta_finish_work, sta_info_finish_work); setup_timer(&local->sta_cleanup, sta_info_cleanup, (unsigned long)local); } void sta_info_stop(struct ieee80211_local *local) { del_timer(&local->sta_cleanup); sta_info_flush(local, NULL); } /** * sta_info_flush - flush matching STA entries from the STA table * * Returns the number of removed STA entries. * * @local: local interface data * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs */ int sta_info_flush(struct ieee80211_local *local, struct ieee80211_sub_if_data *sdata) { struct sta_info *sta, *tmp; int ret = 0; might_sleep(); mutex_lock(&local->sta_mtx); sta_info_finish_pending(local); list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { if (!sdata || sdata == sta->sdata) WARN_ON(__sta_info_destroy(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) if (time_after(jiffies, sta->last_rx + exp_time)) { #ifdef CONFIG_MAC80211_IBSS_DEBUG printk(KERN_DEBUG "%s: expiring inactive STA %pM\n", sdata->name, sta->sta.addr); #endif 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 sta_info *sta, *nxt; /* * Just return a random station if localaddr is NULL * ... first in list. */ for_each_sta_info(hw_to_local(hw), addr, sta, nxt) { if (localaddr && compare_ether_addr(sta->sdata->vif.addr, localaddr) != 0) 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); static void clear_sta_ps_flags(void *_sta) { struct sta_info *sta = _sta; clear_sta_flag(sta, WLAN_STA_PS_DRIVER); clear_sta_flag(sta, WLAN_STA_PS_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; clear_sta_flag(sta, WLAN_STA_SP); BUILD_BUG_ON(BITS_TO_LONGS(STA_TID_NUM) > 1); sta->driver_buffered_tids = 0; if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS)) drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta); skb_queue_head_init(&pending); /* Send all buffered frames to the station */ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) { int count = skb_queue_len(&pending), tmp; skb_queue_splice_tail_init(&sta->tx_filtered[ac], &pending); tmp = skb_queue_len(&pending); filtered += tmp - count; count = tmp; skb_queue_splice_tail_init(&sta->ps_tx_buf[ac], &pending); tmp = skb_queue_len(&pending); buffered += tmp - count; } ieee80211_add_pending_skbs_fn(local, &pending, clear_sta_ps_flags, sta); local->total_ps_buffered -= buffered; sta_info_recalc_tim(sta); #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames " "since STA not sleeping anymore\n", sdata->name, sta->sta.addr, sta->sta.aid, filtered, buffered); #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ } static void ieee80211_send_null_response(struct ieee80211_sub_if_data *sdata, struct sta_info *sta, int tid, enum ieee80211_frame_release_type reason) { struct ieee80211_local *local = sdata->local; struct ieee80211_qos_hdr *nullfunc; struct sk_buff *skb; int size = sizeof(*nullfunc); __le16 fc; bool qos = test_sta_flag(sta, WLAN_STA_WME); struct ieee80211_tx_info *info; 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 = (void *) 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); if (qos) { skb->priority = tid; skb_set_queue_mapping(skb, ieee802_1d_to_ac[tid]); nullfunc->qos_ctrl = cpu_to_le16(tid); if (reason == IEEE80211_FRAME_RELEASE_UAPSD) nullfunc->qos_ctrl |= cpu_to_le16(IEEE80211_QOS_CTL_EOSP); } 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_POLL_RESPONSE | IEEE80211_TX_STATUS_EOSP | IEEE80211_TX_CTL_REQ_TX_STATUS; drv_allow_buffered_frames(local, sta, BIT(tid), 1, reason, false); ieee80211_xmit(sdata, skb); } 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; bool found = false; bool more_data = false; int ac; unsigned long driver_release_tids = 0; struct sk_buff_head frames; /* Service or PS-Poll period starts */ set_sta_flag(sta, WLAN_STA_SP); __skb_queue_head_init(&frames); /* * Get response frame(s) and more data bit for it. */ for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) { unsigned long tids; if (ignored_acs & BIT(ac)) continue; tids = ieee80211_tids_for_ac(ac); if (!found) { driver_release_tids = sta->driver_buffered_tids & tids; if (driver_release_tids) { found = true; } else { 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--; found = true; __skb_queue_tail(&frames, skb); } } /* * 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). */ if (reason == IEEE80211_FRAME_RELEASE_PSPOLL && hweight16(driver_release_tids) > 1) { more_data = true; driver_release_tids = BIT(ffs(driver_release_tids) - 1); break; } } if (!skb_queue_empty(&sta->tx_filtered[ac]) || !skb_queue_empty(&sta->ps_tx_buf[ac])) { more_data = true; break; } } if (!found) { int tid; /* * 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. */ tid = 7 - ((ffs(~ignored_acs) - 1) << 1); ieee80211_send_null_response(sdata, sta, tid, reason); return; } if (!driver_release_tids) { struct sk_buff_head pending; struct sk_buff *skb; int num = 0; u16 tids = 0; 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_POLL_RESPONSE; /* * Use MoreData flag to indicate whether there are * more buffered frames for this STA */ if (!more_data) 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); /* set EOSP for the frame */ if (reason == IEEE80211_FRAME_RELEASE_UAPSD && qoshdr && skb_queue_empty(&frames)) *qoshdr |= IEEE80211_QOS_CTL_EOSP; info->flags |= IEEE80211_TX_STATUS_EOSP | IEEE80211_TX_CTL_REQ_TX_STATUS; if (qoshdr) tids |= BIT(*qoshdr & IEEE80211_QOS_CTL_TID_MASK); else tids |= BIT(0); __skb_queue_tail(&pending, skb); } drv_allow_buffered_frames(local, sta, tids, num, reason, more_data); ieee80211_add_pending_skbs(local, &pending); sta_info_recalc_tim(sta); } else { /* * We need to release a frame that is buffered somewhere in the * driver ... it'll have to handle that. * Note that, as per the comment above, it'll also have to see * if there is more than just one frame on the specific TID that * we're releasing from, and it needs to set the more-data bit * accordingly if we tell it that there's no more data. If we do * tell it there's more data, then of course the more-data bit * needs to be set anyway. */ 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 became empty before returning here from the * release function. * Either way, however, when the driver tells us that the TID * became empty we'll do the TIM recalculation. */ } } 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 = 8; 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); else if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) ieee80211_queue_work(hw, &sta->drv_unblock_wk); } EXPORT_SYMBOL(ieee80211_sta_block_awake); void ieee80211_sta_eosp_irqsafe(struct ieee80211_sta *pubsta) { struct sta_info *sta = container_of(pubsta, struct sta_info, sta); struct ieee80211_local *local = sta->local; struct sk_buff *skb; struct skb_eosp_msg_data *data; trace_api_eosp(local, pubsta); skb = alloc_skb(0, GFP_ATOMIC); if (!skb) { /* too bad ... but race is better than loss */ clear_sta_flag(sta, WLAN_STA_SP); return; } data = (void *)skb->cb; memcpy(data->sta, pubsta->addr, ETH_ALEN); memcpy(data->iface, sta->sdata->vif.addr, ETH_ALEN); skb->pkt_type = IEEE80211_EOSP_MSG; skb_queue_tail(&local->skb_queue, skb); tasklet_schedule(&local->tasklet); } EXPORT_SYMBOL(ieee80211_sta_eosp_irqsafe); 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 >= STA_TID_NUM)) return; 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);