net: aquantia: introduce fwreq mutex

Some of FW operations could be invoked simultaneously,
from f.e. ethtool context and from service service activity work.
Here we introduce a fw mutex to secure and serialize access
to FW logic.
Signed-off-by: Nikita Danilov <ndanilov@aquantia.com>
Signed-off-by: Igor Russkikh <igor.russkikh@aquantia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c

@@ -405,8 +405,10 @@ static int aq_ethtool_get_eee(struct net_device *ndev, struct ethtool_eee *eee)
 	if (!aq_nic->aq_fw_ops->get_eee_rate)
 		return -EOPNOTSUPP;
 
+	mutex_lock(&aq_nic->fwreq_mutex);
 	err = aq_nic->aq_fw_ops->get_eee_rate(aq_nic->aq_hw, &rate,
 					      &supported_rates);
+	mutex_unlock(&aq_nic->fwreq_mutex);
 	if (err < 0)
 		return err;
 
@@ -439,8 +441,10 @@ static int aq_ethtool_set_eee(struct net_device *ndev, struct ethtool_eee *eee)
 		     !aq_nic->aq_fw_ops->set_eee_rate))
 		return -EOPNOTSUPP;
 
+	mutex_lock(&aq_nic->fwreq_mutex);
 	err = aq_nic->aq_fw_ops->get_eee_rate(aq_nic->aq_hw, &rate,
 					      &supported_rates);
+	mutex_unlock(&aq_nic->fwreq_mutex);
 	if (err < 0)
 		return err;
 
@@ -452,20 +456,28 @@ static int aq_ethtool_set_eee(struct net_device *ndev, struct ethtool_eee *eee)
 		cfg->eee_speeds = 0;
 	}
 
-	return aq_nic->aq_fw_ops->set_eee_rate(aq_nic->aq_hw, rate);
+	mutex_lock(&aq_nic->fwreq_mutex);
+	err = aq_nic->aq_fw_ops->set_eee_rate(aq_nic->aq_hw, rate);
+	mutex_unlock(&aq_nic->fwreq_mutex);
+
+	return err;
 }
 
 static int aq_ethtool_nway_reset(struct net_device *ndev)
 {
 	struct aq_nic_s *aq_nic = netdev_priv(ndev);
+	int err = 0;
 
 	if (unlikely(!aq_nic->aq_fw_ops->renegotiate))
 		return -EOPNOTSUPP;
 
-	if (netif_running(ndev))
-		return aq_nic->aq_fw_ops->renegotiate(aq_nic->aq_hw);
+	if (netif_running(ndev)) {
+		mutex_lock(&aq_nic->fwreq_mutex);
+		err = aq_nic->aq_fw_ops->renegotiate(aq_nic->aq_hw);
+		mutex_unlock(&aq_nic->fwreq_mutex);
+	}
 
-	return 0;
+	return err;
 }
 
 static void aq_ethtool_get_pauseparam(struct net_device *ndev,
@@ -503,7 +515,9 @@ static int aq_ethtool_set_pauseparam(struct net_device *ndev,
 	else
 		aq_nic->aq_hw->aq_nic_cfg->flow_control &= ~AQ_NIC_FC_TX;
 
+	mutex_lock(&aq_nic->fwreq_mutex);
 	err = aq_nic->aq_fw_ops->set_flow_control(aq_nic->aq_hw);
+	mutex_unlock(&aq_nic->fwreq_mutex);
 
 	return err;
 }

drivers/net/ethernet/aquantia/atlantic/aq_nic.c

@@ -234,8 +234,10 @@ int aq_nic_ndev_register(struct aq_nic_s *self)
 	if (err)
 		goto err_exit;
 
+	mutex_lock(&self->fwreq_mutex);
 	err = self->aq_fw_ops->get_mac_permanent(self->aq_hw,
 			    self->ndev->dev_addr);
+	mutex_unlock(&self->fwreq_mutex);
 	if (err)
 		goto err_exit;
 
@@ -304,7 +306,9 @@ int aq_nic_init(struct aq_nic_s *self)
 	unsigned int i = 0U;
 
 	self->power_state = AQ_HW_POWER_STATE_D0;
+	mutex_lock(&self->fwreq_mutex);
 	err = self->aq_hw_ops->hw_reset(self->aq_hw);
+	mutex_unlock(&self->fwreq_mutex);
 	if (err < 0)
 		goto err_exit;
 
@@ -871,7 +875,9 @@ int aq_nic_set_link_ksettings(struct aq_nic_s *self,
 		self->aq_nic_cfg.is_autoneg = false;
 	}
 
+	mutex_lock(&self->fwreq_mutex);
 	err = self->aq_fw_ops->set_link_speed(self->aq_hw, rate);
+	mutex_unlock(&self->fwreq_mutex);
 	if (err < 0)
 		goto err_exit;
 
@@ -931,14 +937,22 @@ void aq_nic_deinit(struct aq_nic_s *self)
 		self->aq_vecs > i; ++i, aq_vec = self->aq_vec[i])
 		aq_vec_deinit(aq_vec);
 
-	self->aq_fw_ops->deinit(self->aq_hw);
+	if (likely(self->aq_fw_ops->deinit)) {
+		mutex_lock(&self->fwreq_mutex);
+		self->aq_fw_ops->deinit(self->aq_hw);
+		mutex_unlock(&self->fwreq_mutex);
+	}
 
 	if (self->power_state != AQ_HW_POWER_STATE_D0 ||
-	    self->aq_hw->aq_nic_cfg->wol) {
-		self->aq_fw_ops->set_power(self->aq_hw,
-					   self->power_state,
-					   self->ndev->dev_addr);
-	}
+	    self->aq_hw->aq_nic_cfg->wol)
+		if (likely(self->aq_fw_ops->set_power)) {
+			mutex_lock(&self->fwreq_mutex);
+			self->aq_fw_ops->set_power(self->aq_hw,
+						   self->power_state,
+						   self->ndev->dev_addr);
+			mutex_unlock(&self->fwreq_mutex);
+		}
+
 
 err_exit:;
 }

drivers/net/ethernet/aquantia/atlantic/aq_nic.h

@@ -105,6 +105,8 @@ struct aq_nic_s {
 	struct pci_dev *pdev;
 	unsigned int msix_entry_mask;
 	u32 irqvecs;
+	/* mutex to serialize FW interface access operations */
+	struct mutex fwreq_mutex;
 	struct aq_hw_rx_fltrs_s aq_hw_rx_fltrs;
 };
 

drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c

@@ -231,6 +231,8 @@ static int aq_pci_probe(struct pci_dev *pdev,
 	SET_NETDEV_DEV(ndev, &pdev->dev);
 	pci_set_drvdata(pdev, self);
 
+	mutex_init(&self->fwreq_mutex);
+
 	err = aq_pci_probe_get_hw_by_id(pdev, &self->aq_hw_ops,
 					&aq_nic_get_cfg(self)->aq_hw_caps);
 	if (err)