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>

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 28ac0d4..70428e9 100644 (file)
--- 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");