iwlwifi: more priv->mutex serialization

Check status bits with mutex taken, because when we wait for mutex
unlock, status can change. Patch should also make remaining sync
commands be send with priv->mutex taken. That will prevent execute
these commands when we are currently reset firmware, what could
possibly cause troubles.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 20 insertions, 14 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 28ac0d44555e..70428e9b9f76 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -483,12 +483,14 @@ static void iwl_bg_bt_full_concurrency(struct work_struct *work)
                 container_of(work, struct iwl_priv, bt_full_concurrency);
         struct iwl_rxon_context *ctx;
 
+        mutex_lock(&priv->mutex);
+
         if (test_bit(STATUS_EXIT_PENDING, &priv->status))
-                return;
+                goto out;
 
         /* dont send host command if rf-kill is on */
         if (!iwl_is_ready_rf(priv))
-                return;
+                goto out;
 
         IWL_DEBUG_INFO(priv, "BT coex in %s mode\n",
                        priv->bt_full_concurrent ?
@@ -498,15 +500,15 @@ static void iwl_bg_bt_full_concurrency(struct work_struct *work)
          * LQ & RXON updated cmds must be sent before BT Config cmd
          * to avoid 3-wire collisions
          */
-        mutex_lock(&priv->mutex);
         for_each_context(priv, ctx) {
                 if (priv->cfg->ops->hcmd->set_rxon_chain)
                         priv->cfg->ops->hcmd->set_rxon_chain(priv, ctx);
                 iwlcore_commit_rxon(priv, ctx);
         }
-        mutex_unlock(&priv->mutex);
 
         priv->cfg->ops->hcmd->send_bt_config(priv);
+out:
+        mutex_unlock(&priv->mutex);
 }
 
 /**
@@ -2620,10 +2622,13 @@ static void iwl_bg_init_alive_start(struct work_struct *data)
         struct iwl_priv *priv =
             container_of(data, struct iwl_priv, init_alive_start.work);
 
-        if (test_bit(STATUS_EXIT_PENDING, &priv->status))
+        mutex_lock(&priv->mutex);
+
+        if (test_bit(STATUS_EXIT_PENDING, &priv->status)) {
+                mutex_unlock(&priv->mutex);
                 return;
+        }
 
-        mutex_lock(&priv->mutex);
         priv->cfg->ops->lib->init_alive_start(priv);
         mutex_unlock(&priv->mutex);
 }
@@ -2633,15 +2638,16 @@ static void iwl_bg_alive_start(struct work_struct *data)
         struct iwl_priv *priv =
             container_of(data, struct iwl_priv, alive_start.work);
 
+        mutex_lock(&priv->mutex);
         if (test_bit(STATUS_EXIT_PENDING, &priv->status))
-                return;
+                goto unlock;
 
         /* enable dram interrupt */
         if (priv->cfg->ops->lib->isr_ops.reset)
                 priv->cfg->ops->lib->isr_ops.reset(priv);
 
-        mutex_lock(&priv->mutex);
         iwl_alive_start(priv);
+unlock:
         mutex_unlock(&priv->mutex);
 }
 
@@ -3267,21 +3273,22 @@ void iwlagn_mac_channel_switch(struct ieee80211_hw *hw,
 
         IWL_DEBUG_MAC80211(priv, "enter\n");
 
+        mutex_lock(&priv->mutex);
+
         if (iwl_is_rfkill(priv))
-                goto out_exit;
+                goto out;
 
         if (test_bit(STATUS_EXIT_PENDING, &priv->status) ||
             test_bit(STATUS_SCANNING, &priv->status))
-                goto out_exit;
+                goto out;
 
         if (!iwl_is_associated_ctx(ctx))
-                goto out_exit;
+                goto out;
 
         /* channel switch in progress */
         if (priv->switch_rxon.switch_in_progress == true)
-                goto out_exit;
+                goto out;
 
-        mutex_lock(&priv->mutex);
         if (priv->cfg->ops->lib->set_channel_switch) {
 
                 ch = channel->hw_value;
@@ -3337,7 +3344,6 @@ void iwlagn_mac_channel_switch(struct ieee80211_hw *hw,
         }
 out:
         mutex_unlock(&priv->mutex);
-out_exit:
         if (!priv->switch_rxon.switch_in_progress)
                 ieee80211_chswitch_done(ctx->vif, false);
         IWL_DEBUG_MAC80211(priv, "leave\n");