diff options
Diffstat (limited to 'net/mac80211/sta_info.c')
| -rw-r--r-- | net/mac80211/sta_info.c | 1516 |
1 files changed, 1516 insertions, 0 deletions
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c new file mode 100644 index 0000000..0d1836e --- /dev/null +++ b/net/mac80211/sta_info.c @@ -0,0 +1,1516 @@ +/* + * Copyright 2002-2005, Instant802 Networks, Inc. + * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/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/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. + */ + +/* Caller must hold local->sta_mtx */ +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_mtx)); + 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_mtx)); + if (rcu_access_pointer(s->hnext)) { + rcu_assign_pointer(s->hnext, sta->hnext); + return 0; + } + + return -ENOENT; +} + +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; + + /* + * At this point, when being called as call_rcu callback, + * 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. + * + * Note though that this still uses the sdata and even + * calls the driver in AP and mesh mode, so interfaces + * of those types mush use call sta_info_flush_cleanup() + * (typically via sta_info_flush()) before deconfiguring + * the driver. + * + * In station mode, nothing happens here so it doesn't + * have to (and doesn't) do that, this is intentional to + * speed up roaming. + */ + + if (test_sta_flag(sta, WLAN_STA_PS_STA)) { + 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); + + atomic_dec(&ps->num_sta_ps); + sta_info_recalc_tim(sta); + } + + 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_unblock_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++) { + 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); + } + + sta_info_free(local, sta); +} + +void ieee80211_cleanup_sdata_stas(struct ieee80211_sub_if_data *sdata) +{ + struct sta_info *sta; + + spin_lock_bh(&sdata->cleanup_stations_lock); + while (!list_empty(&sdata->cleanup_stations)) { + sta = list_first_entry(&sdata->cleanup_stations, + struct sta_info, list); + list_del(&sta->list); + spin_unlock_bh(&sdata->cleanup_stations_lock); + + cleanup_single_sta(sta); + + spin_lock_bh(&sdata->cleanup_stations_lock); + } + + spin_unlock_bh(&sdata->cleanup_stations_lock); +} + +static void free_sta_rcu(struct rcu_head *h) +{ + struct sta_info *sta = container_of(h, struct sta_info, rcu_head); + struct ieee80211_sub_if_data *sdata = sta->sdata; + + spin_lock(&sdata->cleanup_stations_lock); + list_add_tail(&sta->list, &sdata->cleanup_stations); + spin_unlock(&sdata->cleanup_stations_lock); + + ieee80211_queue_work(&sdata->local->hw, &sdata->cleanup_stations_wk); +} + +/* 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_mtx)); + while (sta) { + if (sta->sdata == sdata && + ether_addr_equal(sta->sta.addr, addr)) + break; + sta = rcu_dereference_check(sta->hnext, + 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_mtx)); + while (sta) { + if ((sta->sdata == sdata || + (sta->sdata->bss && sta->sdata->bss == sdata->bss)) && + ether_addr_equal(sta->sta.addr, addr)) + break; + sta = rcu_dereference_check(sta->hnext, + 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 - 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) +{ + if (sta->rate_ctrl) + rate_control_free_sta(sta); + + sta_dbg(sta->sdata, "Destroyed STA %pM\n", sta->sta.addr); + + kfree(sta); +} + +/* Caller must hold local->sta_mtx */ +static void sta_info_hash_add(struct ieee80211_local *local, + struct sta_info *sta) +{ + lockdep_assert_held(&local->sta_mtx); + 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)) { + local_bh_disable(); + ieee80211_sta_ps_deliver_wakeup(sta); + local_bh_enable(); + } 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 = local->rate_ctrl; + sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, + &sta->sta, gfp); + if (!sta->rate_ctrl_priv) + return -ENOMEM; + + return 0; +} + +struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, + const 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); +#ifdef CPTCFG_MAC80211_MESH + if (ieee80211_vif_is_mesh(&sdata->vif) && + !sdata->u.mesh.user_mpm) + init_timer(&sta->plink_timer); +#endif + + memcpy(sta->sta.addr, addr, ETH_ALEN); + sta->local = local; + sta->sdata = sdata; + sta->last_rx = jiffies; + + sta->sta_state = IEEE80211_STA_NONE; + + 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 < IEEE80211_NUM_TIDS; 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 < IEEE80211_NUM_TIDS; i++) + sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX); + + sta->sta.smps_mode = IEEE80211_SMPS_OFF; + + sta_dbg(sdata, "Allocated STA %pM\n", sta->sta.addr); + + return sta; +} + +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_multicast_ether_addr(sta->sta.addr))) + return -EINVAL; + + 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; +} + +/* + * 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; + 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_err; + } + + /* notify driver */ + err = sta_info_insert_drv_state(local, sdata, sta); + if (err) + goto out_err; + + local->num_sta++; + local->sta_generation++; + smp_mb(); + + /* make the station visible */ + sta_info_hash_add(local, sta); + + list_add_rcu(&sta->list, &local->sta_list); + + set_sta_flag(sta, WLAN_STA_INSERTED); + + 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); + + 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_err: + mutex_unlock(&local->sta_mtx); + rcu_read_lock(); + return err; +} + +int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU) +{ + struct ieee80211_local *local = sta->local; + int err = 0; + + might_sleep(); + + err = sta_info_insert_check(sta); + if (err) { + rcu_read_lock(); + goto out_free; + } + + mutex_lock(&local->sta_mtx); + + err = sta_info_insert_finish(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; +} + +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; + } +} + +void sta_info_recalc_tim(struct sta_info *sta) +{ + 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; + + 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; + id = sta->sta.aid; +#ifdef CPTCFG_MAC80211_MESH + } else if (ieee80211_vif_is_mesh(&sta->sdata->vif)) { + ps = &sta->sdata->u.mesh.ps; + /* TIM map only for PLID <= IEEE80211_MAX_AID */ + id = le16_to_cpu(sta->plid) % IEEE80211_MAX_AID; +#endif + } else { + 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_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) { + 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); +} + +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; +} + +int __must_check __sta_info_destroy(struct sta_info *sta) +{ + struct ieee80211_local *local; + struct ieee80211_sub_if_data *sdata; + int ret; + + 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); + + ret = sta_info_hash_del(local, sta); + if (ret) + return ret; + + list_del_rcu(&sta->list); + + /* this always calls synchronize_net() */ + ieee80211_free_sta_keys(local, sta); + + sta->dead = true; + + local->num_sta--; + local->sta_generation++; + + if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) + RCU_INIT_POINTER(sdata->u.vlan.sta, NULL); + + 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); + + cfg80211_del_sta(sdata->dev, sta->sta.addr, GFP_KERNEL); + + rate_control_remove_sta_debugfs(sta); + ieee80211_sta_debugfs_remove(sta); + + call_rcu(&sta->rcu_head, free_sta_rcu); + + 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(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->tim_lock); + mutex_init(&local->sta_mtx); + INIT_LIST_HEAD(&local->sta_list); + + setup_timer(&local->sta_cleanup, sta_info_cleanup, + (unsigned long)local); +} + +void sta_info_stop(struct ieee80211_local *local) +{ + del_timer_sync(&local->sta_cleanup); +} + + +int sta_info_flush_defer(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_local *local = sdata->local; + struct sta_info *sta, *tmp; + int ret = 0; + + might_sleep(); + + mutex_lock(&local->sta_mtx); + list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { + if (sdata == sta->sdata) { + WARN_ON(__sta_info_destroy(sta)); + ret++; + } + } + mutex_unlock(&local->sta_mtx); + + return ret; +} + +void sta_info_flush_cleanup(struct ieee80211_sub_if_data *sdata) +{ + ieee80211_cleanup_sdata_stas(sdata); + cancel_work_sync(&sdata->cleanup_stations_wk); +} + +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 (sdata != sta->sdata) + continue; + + if (time_after(jiffies, sta->last_rx + 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 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 && + !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); + +static void clear_sta_ps_flags(void *_sta) +{ + struct sta_info *sta = _sta; + struct ieee80211_sub_if_data *sdata = sta->sdata; + struct ps_data *ps; + + if (sdata->vif.type == NL80211_IFTYPE_AP || + 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_DRIVER); + if (test_and_clear_sta_flag(sta, WLAN_STA_PS_STA)) + atomic_dec(&ps->num_sta_ps); +} + +/* 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; + unsigned long flags; + + clear_sta_flag(sta, WLAN_STA_SP); + + BUILD_BUG_ON(BITS_TO_LONGS(IEEE80211_NUM_TIDS) > 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; + + 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_fn(local, &pending, clear_sta_ps_flags, sta); + + 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 not sleeping anymore\n", + sta->sta.addr, sta->sta.aid, filtered, buffered); +} + +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; + 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 = (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); + + 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); + } + + 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; + + drv_allow_buffered_frames(local, sta, BIT(tid), 1, reason, false); + + skb->dev = sdata->dev; + + rcu_read_lock(); + chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); + if (WARN_ON(!chanctx_conf)) { + rcu_read_unlock(); + kfree_skb(skb); + return; + } + + ieee80211_xmit(sdata, skb, chanctx_conf->def.chan->band); + rcu_read_unlock(); +} + +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_NO_PS_BUFFER; + + /* + * 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); + + /* end service period after last frame */ + if (skb_queue_empty(&frames)) { + if (reason == IEEE80211_FRAME_RELEASE_UAPSD && + qoshdr) + *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(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_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; + + 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); + +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); + break; + case IEEE80211_STA_ASSOC: + if (sta->sta_state == IEEE80211_STA_AUTH) { + set_bit(WLAN_STA_ASSOC, &sta->_flags); + } else if (sta->sta_state == IEEE80211_STA_AUTHORIZED) { + if (sta->sdata->vif.type == NL80211_IFTYPE_AP || + (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && + !sta->sdata->u.vlan.sta)) + atomic_dec(&sta->sdata->bss->num_mcast_sta); + clear_bit(WLAN_STA_AUTHORIZED, &sta->_flags); + } + break; + case IEEE80211_STA_AUTHORIZED: + if (sta->sta_state == IEEE80211_STA_ASSOC) { + if (sta->sdata->vif.type == NL80211_IFTYPE_AP || + (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && + !sta->sdata->u.vlan.sta)) + atomic_inc(&sta->sdata->bss->num_mcast_sta); + set_bit(WLAN_STA_AUTHORIZED, &sta->_flags); + } + break; + default: + break; + } + + sta->sta_state = new_state; + + return 0; +} |