diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index eca6063e287c60..8e5b892834bc26 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -855,18 +855,15 @@ struct ieee80211_local { /* Station data */ /* - * The mutex only protects the list and counter, - * reads are done in RCU. - * Additionally, the lock protects the hash table, - * the pending list and each BSS's TIM bitmap. + * The mutex only protects the list, hash table and + * counter, reads are done with RCU. */ struct mutex sta_mtx; - spinlock_t sta_lock; + spinlock_t tim_lock; unsigned long num_sta; - struct list_head sta_list, sta_pending_list; + struct list_head sta_list; struct sta_info __rcu *sta_hash[STA_HASH_SIZE]; struct timer_list sta_cleanup; - struct work_struct sta_finish_work; int sta_generation; struct sk_buff_head pending[IEEE80211_MAX_QUEUES]; diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index aa9293d7f3f0bb..2db01e9541e7ea 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -62,14 +62,14 @@ * freed before they are done using it. */ -/* Caller must hold local->sta_lock */ +/* 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_lock)); + lockdep_is_held(&local->sta_mtx)); if (!s) return -ENOENT; if (s == sta) { @@ -81,7 +81,7 @@ static int sta_info_hash_del(struct ieee80211_local *local, while (rcu_access_pointer(s->hnext) && rcu_access_pointer(s->hnext) != sta) s = rcu_dereference_protected(s->hnext, - lockdep_is_held(&local->sta_lock)); + lockdep_is_held(&local->sta_mtx)); if (rcu_access_pointer(s->hnext)) { RCU_INIT_POINTER(s->hnext, sta->hnext); return 0; @@ -98,14 +98,12 @@ struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata, 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; @@ -119,14 +117,12 @@ struct sta_info *sta_info_get_rx(struct ieee80211_sub_if_data *sdata, 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; @@ -143,7 +139,6 @@ struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata, 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 || @@ -152,7 +147,6 @@ struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *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; @@ -169,7 +163,6 @@ struct sta_info *sta_info_get_bss_rx(struct ieee80211_sub_if_data *sdata, 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 || @@ -177,7 +170,6 @@ struct sta_info *sta_info_get_bss_rx(struct ieee80211_sub_if_data *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; @@ -228,10 +220,11 @@ void sta_info_free(struct ieee80211_local *local, struct sta_info *sta) kfree(sta); } -/* Caller must hold local->sta_lock */ +/* 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_INIT_POINTER(local->sta_hash[STA_HASH(sta->sta.addr)], sta); } @@ -339,89 +332,6 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, 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 */ - err = drv_sta_add(local, sdata, &sta->sta); - if (err) { - if (sdata->vif.type != NL80211_IFTYPE_ADHOC) - 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; - - sdata = sta->sdata; - } - - if (!dummy_reinsert) { - 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; @@ -441,70 +351,24 @@ static int sta_info_insert_check(struct sta_info *sta) 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) +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; - 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 + * only accept a scenario of a second call to sta_info_insert_finish * with a dummy station entry that was inserted earlier * in that case - assume that the dummy station flag should * be removed. @@ -514,20 +378,47 @@ static int sta_info_insert_non_ibss(struct sta_info *sta) __acquires(RCU) 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; + err = -EEXIST; + goto out_err; } } - spin_unlock_irqrestore(&local->sta_lock, flags); + if (!sta->dummy || dummy_reinsert) { + /* notify driver */ + err = drv_sta_add(local, sdata, &sta->sta); + if (err) { + if (sdata->vif.type != NL80211_IFTYPE_ADHOC) + goto out_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; + } - err = sta_info_finish_insert(sta, false, dummy_reinsert); - if (err) { - mutex_unlock(&local->sta_mtx); - rcu_read_lock(); - return err; + if (!dummy_reinsert) { + local->num_sta++; + local->sta_generation++; + smp_mb(); + + /* make the station visible */ + sta_info_hash_add(local, sta); + + list_add(&sta->list, &local->sta_list); + } else { + sta->dummy = false; + } + + if (!sta->dummy) { + struct station_info sinfo; + + 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); } #ifdef CONFIG_MAC80211_VERBOSE_DEBUG @@ -543,47 +434,28 @@ static int sta_info_insert_non_ibss(struct sta_info *sta) __acquires(RCU) 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; - struct ieee80211_sub_if_data *sdata = sta->sdata; int err = 0; + might_sleep(); + 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); + err = sta_info_insert_finish(sta); if (err) goto out_free; @@ -617,7 +489,7 @@ int sta_info_reinsert(struct sta_info *sta) might_sleep(); - err = sta_info_insert_non_ibss(sta); + err = sta_info_insert_finish(sta); rcu_read_unlock(); return err; } @@ -704,7 +576,7 @@ void sta_info_recalc_tim(struct sta_info *sta) } done: - spin_lock_irqsave(&local->sta_lock, flags); + spin_lock_irqsave(&local->tim_lock, flags); if (indicate_tim) __bss_tim_set(bss, sta->sta.aid); @@ -717,7 +589,7 @@ void sta_info_recalc_tim(struct sta_info *sta) local->tim_in_locked_section = false; } - spin_unlock_irqrestore(&local->sta_lock, flags); + spin_unlock_irqrestore(&local->tim_lock, flags); } static bool sta_info_buffer_expired(struct sta_info *sta, struct sk_buff *skb) @@ -841,7 +713,6 @@ 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; struct tid_ampdu_tx *tid_tx; @@ -862,15 +733,12 @@ static int __must_check __sta_info_destroy(struct sta_info *sta) 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; + list_del(&sta->list); + mutex_lock(&local->key_mtx); for (i = 0; i < NUM_DEFAULT_KEYS; i++) __ieee80211_key_free(key_mtx_dereference(local, sta->gtk[i])); @@ -1025,11 +893,9 @@ static void sta_info_cleanup(unsigned long data) void sta_info_init(struct ieee80211_local *local) { - spin_lock_init(&local->sta_lock); + spin_lock_init(&local->tim_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); @@ -1058,9 +924,6 @@ int sta_info_flush(struct ieee80211_local *local, 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)); diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 6bbd6cccb4a050..ab033fd00b72bd 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -2333,9 +2333,9 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw, } else { unsigned long flags; - spin_lock_irqsave(&local->sta_lock, flags); + spin_lock_irqsave(&local->tim_lock, flags); ieee80211_beacon_add_tim(ap, skb, beacon); - spin_unlock_irqrestore(&local->sta_lock, flags); + spin_unlock_irqrestore(&local->tim_lock, flags); } if (tim_offset)