if (!s)
return -ENOENT;
if (s == sta) {
- rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)],
+ RCU_INIT_POINTER(local->sta_hash[STA_HASH(sta->sta.addr)],
s->hnext);
return 0;
}
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);
+ RCU_INIT_POINTER(s->hnext, sta->hnext);
return 0;
}
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));
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));
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);
+ RCU_INIT_POINTER(local->sta_hash[STA_HASH(sta->sta.addr)], sta);
}
static void sta_unblock(struct work_struct *wk)
return sta;
}
-static int sta_info_finish_insert(struct sta_info *sta, bool async)
+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;
lockdep_assert_held(&local->sta_mtx);
- /* 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;
+ 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);
+ if (async)
+ wiphy_debug(local->hw.wiphy,
+ "Finished adding IBSS STA %pM\n",
+ sta->sta.addr);
#endif
+ }
+
+ sdata = sta->sdata;
}
- sdata = sta->sdata;
+ if (!dummy_reinsert) {
+ if (!async) {
+ local->num_sta++;
+ local->sta_generation++;
+ smp_mb();
- 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);
+ }
- /* 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;
}
- list_add(&sta->list, &local->sta_list);
-
- ieee80211_sta_debugfs_add(sta);
- rate_control_add_sta_debugfs(sta);
-
- sinfo.filled = 0;
- sinfo.generation = local->sta_generation;
- cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL);
+ 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;
}
list_del(&sta->list);
spin_unlock_irqrestore(&local->sta_lock, flags);
- sta_info_finish_insert(sta, true);
+ sta_info_finish_insert(sta, true, false);
spin_lock_irqsave(&local->sta_lock, flags);
}
mutex_unlock(&local->sta_mtx);
}
-int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU)
+static int sta_info_insert_check(struct sta_info *sta)
{
- struct ieee80211_local *local = sta->local;
struct ieee80211_sub_if_data *sdata = sta->sdata;
- unsigned long flags;
- int err = 0;
/*
* 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))) {
- err = -ENETDOWN;
- rcu_read_lock();
- goto out_free;
- }
+ 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))) {
- err = -EINVAL;
+ 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();
- goto out_free;
+ return -EEXIST;
}
- /*
- * 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) {
- spin_lock_irqsave(&local->sta_lock, flags);
- /* check if STA exists already */
- if (sta_info_get_bss(sdata, sta->sta.addr)) {
- spin_unlock_irqrestore(&local->sta_lock, flags);
- rcu_read_lock();
- err = -EEXIST;
- goto out_free;
- }
-
- local->num_sta++;
- local->sta_generation++;
- smp_mb();
- sta_info_hash_add(local, sta);
+ local->num_sta++;
+ local->sta_generation++;
+ smp_mb();
+ sta_info_hash_add(local, sta);
- list_add_tail(&sta->list, &local->sta_pending_list);
+ list_add_tail(&sta->list, &local->sta_pending_list);
- rcu_read_lock();
- spin_unlock_irqrestore(&local->sta_lock, flags);
+ 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);
+ 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);
+ ieee80211_queue_work(&local->hw, &local->sta_finish_work);
- return 0;
- }
+ 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
- * below this point, which inserts a station with sleeping,
+ * 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. It still seems to race against the
- * above code 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.
+ * the mutex locked.
*/
- might_sleep();
-
- mutex_lock(&local->sta_mtx);
-
spin_lock_irqsave(&local->sta_lock, flags);
- /* check if STA exists already */
- if (sta_info_get_bss(sdata, sta->sta.addr)) {
- spin_unlock_irqrestore(&local->sta_lock, flags);
- mutex_unlock(&local->sta_mtx);
- rcu_read_lock();
- err = -EEXIST;
- goto out_free;
+ /*
+ * 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);
+ err = sta_info_finish_insert(sta, false, dummy_reinsert);
if (err) {
mutex_unlock(&local->sta_mtx);
rcu_read_lock();
- goto out_free;
+ return err;
}
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
- wiphy_debug(local->hw.wiphy, "Inserted STA %pM\n", sta->sta.addr);
+ 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 */
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);
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)
{
/*
local->sta_generation++;
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
- rcu_assign_pointer(sdata->u.vlan.sta, NULL);
+ RCU_INIT_POINTER(sdata->u.vlan.sta, NULL);
if (sta->uploaded) {
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
int ret;
mutex_lock(&sdata->local->sta_mtx);
- sta = sta_info_get(sdata, addr);
+ sta = sta_info_get_rx(sdata, addr);
ret = __sta_info_destroy(sta);
mutex_unlock(&sdata->local->sta_mtx);
int ret;
mutex_lock(&sdata->local->sta_mtx);
- sta = sta_info_get_bss(sdata, addr);
+ sta = sta_info_get_bss_rx(sdata, addr);
ret = __sta_info_destroy(sta);
mutex_unlock(&sdata->local->sta_mtx);
git.openpandora.org / pandora-kernel.git / blobdiff