[PATCH] Fix locking in gianfar
This patch fixes several bugs in the gianfar driver, including a major one
where spinlocks were horribly broken:
* Split gianfar locks into two types: TX and RX
* Made it so gfar_start() now clears RHALT
* Fixed a bug where calling gfar_start_xmit() with interrupts off would
corrupt the interrupt state
* Fixed a bug where a frame could potentially arrive, and never be handled
(if no more frames arrived
* Fixed a bug where the rx_work_limit would never be observed by the rx
completion code
* Fixed a bug where the interrupt handlers were not actually protected by
their spinlocks
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/gianfar_ethtool.c b/drivers/net/gianfar_ethtool.c
index 5de7b2e..d69698c 100644
--- a/drivers/net/gianfar_ethtool.c
+++ b/drivers/net/gianfar_ethtool.c
@@ -455,10 +455,14 @@
/* Halt TX and RX, and process the frames which
* have already been received */
- spin_lock_irqsave(&priv->lock, flags);
+ spin_lock_irqsave(&priv->txlock, flags);
+ spin_lock(&priv->rxlock);
+
gfar_halt(dev);
gfar_clean_rx_ring(dev, priv->rx_ring_size);
- spin_unlock_irqrestore(&priv->lock, flags);
+
+ spin_unlock(&priv->rxlock);
+ spin_unlock_irqrestore(&priv->txlock, flags);
/* Now we take down the rings to rebuild them */
stop_gfar(dev);
@@ -488,10 +492,14 @@
/* Halt TX and RX, and process the frames which
* have already been received */
- spin_lock_irqsave(&priv->lock, flags);
+ spin_lock_irqsave(&priv->txlock, flags);
+ spin_lock(&priv->rxlock);
+
gfar_halt(dev);
gfar_clean_rx_ring(dev, priv->rx_ring_size);
- spin_unlock_irqrestore(&priv->lock, flags);
+
+ spin_unlock(&priv->rxlock);
+ spin_unlock_irqrestore(&priv->txlock, flags);
/* Now we take down the rings to rebuild them */
stop_gfar(dev);
@@ -523,7 +531,7 @@
if (!(priv->einfo->device_flags & FSL_GIANFAR_DEV_HAS_CSUM))
return -EOPNOTSUPP;
- spin_lock_irqsave(&priv->lock, flags);
+ spin_lock_irqsave(&priv->txlock, flags);
gfar_halt(dev);
if (data)
@@ -532,7 +540,7 @@
dev->features &= ~NETIF_F_IP_CSUM;
gfar_start(dev);
- spin_unlock_irqrestore(&priv->lock, flags);
+ spin_unlock_irqrestore(&priv->txlock, flags);
return 0;
}