1 files changed, 40 insertions, 61 deletions

diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
index b9de31ea7fc4..01bb854c7f62 100644
--- a/drivers/net/xen-netback/interface.c
+++ b/drivers/net/xen-netback/interface.c
@@ -34,7 +34,6 @@
 #include <linux/ethtool.h>
 #include <linux/rtnetlink.h>
 #include <linux/if_vlan.h>
-#include <linux/vmalloc.h>
 
 #include <xen/events.h>
 #include <asm/xen/hypercall.h>
@@ -47,6 +46,11 @@ int xenvif_schedulable(struct xenvif *vif)
 	return netif_running(vif->dev) && netif_carrier_ok(vif->dev);
 }
 
+static int xenvif_rx_schedulable(struct xenvif *vif)
+{
+	return xenvif_schedulable(vif) && !xenvif_rx_ring_full(vif);
+}
+
 static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
 {
 	struct xenvif *vif = dev_id;
@@ -100,8 +104,8 @@ static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
 {
 	struct xenvif *vif = dev_id;
 
-	vif->rx_event = true;
-	xenvif_kick_thread(vif);
+	if (xenvif_rx_schedulable(vif))
+		netif_wake_queue(vif->dev);
 
 	return IRQ_HANDLED;
 }
@@ -117,35 +121,24 @@ static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
 static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct xenvif *vif = netdev_priv(dev);
-	int min_slots_needed;
 
 	BUG_ON(skb->dev != dev);
 
 	/* Drop the packet if vif is not ready */
-	if (vif->task == NULL || !xenvif_schedulable(vif))
+	if (vif->task == NULL)
 		goto drop;
 
-	/* At best we'll need one slot for the header and one for each
-	 * frag.
-	 */
-	min_slots_needed = 1 + skb_shinfo(skb)->nr_frags;
+	/* Drop the packet if the target domain has no receive buffers. */
+	if (!xenvif_rx_schedulable(vif))
+		goto drop;
 
-	/* If the skb is GSO then we'll also need an extra slot for the
-	 * metadata.
-	 */
-	if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 ||
-	    skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
-		min_slots_needed++;
+	/* Reserve ring slots for the worst-case number of fragments. */
+	vif->rx_req_cons_peek += xenvif_count_skb_slots(vif, skb);
 
-	/* If the skb can't possibly fit in the remaining slots
-	 * then turn off the queue to give the ring a chance to
-	 * drain.
-	 */
-	if (!xenvif_rx_ring_slots_available(vif, min_slots_needed))
-		xenvif_stop_queue(vif);
+	if (vif->can_queue && xenvif_must_stop_queue(vif))
+		netif_stop_queue(dev);
 
-	skb_queue_tail(&vif->rx_queue, skb);
-	xenvif_kick_thread(vif);
+	xenvif_queue_tx_skb(vif, skb);
 
 	return NETDEV_TX_OK;
 
@@ -155,6 +148,12 @@ static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	return NETDEV_TX_OK;
 }
 
+void xenvif_notify_tx_completion(struct xenvif *vif)
+{
+	if (netif_queue_stopped(vif->dev) && xenvif_rx_schedulable(vif))
+		netif_wake_queue(vif->dev);
+}
+
 static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
 {
 	struct xenvif *vif = netdev_priv(dev);
@@ -215,14 +214,10 @@ static netdev_features_t xenvif_fix_features(struct net_device *dev,
 
 	if (!vif->can_sg)
 		features &= ~NETIF_F_SG;
-	if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV4))
+	if (!vif->gso && !vif->gso_prefix)
 		features &= ~NETIF_F_TSO;
-	if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV6))
-		features &= ~NETIF_F_TSO6;
-	if (!vif->ip_csum)
+	if (!vif->csum)
 		features &= ~NETIF_F_IP_CSUM;
-	if (!vif->ipv6_csum)
-		features &= ~NETIF_F_IPV6_CSUM;
 
 	return features;
 }
@@ -308,31 +303,21 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
 	SET_NETDEV_DEV(dev, parent);
 
 	vif = netdev_priv(dev);
-
-	vif->grant_copy_op = vmalloc(sizeof(struct gnttab_copy) *
-				     MAX_GRANT_COPY_OPS);
-	if (vif->grant_copy_op == NULL) {
-		pr_warn("Could not allocate grant copy space for %s\n", name);
-		free_netdev(dev);
-		return ERR_PTR(-ENOMEM);
-	}
-
 	vif->domid  = domid;
 	vif->handle = handle;
 	vif->can_sg = 1;
-	vif->ip_csum = 1;
+	vif->csum = 1;
 	vif->dev = dev;
 
 	vif->credit_bytes = vif->remaining_credit = ~0UL;
 	vif->credit_usec  = 0UL;
 	init_timer(&vif->credit_timeout);
-	vif->credit_window_start = get_jiffies_64();
+	/* Initialize 'expires' now: it's used to track the credit window. */
+	vif->credit_timeout.expires = jiffies;
 
 	dev->netdev_ops	= &xenvif_netdev_ops;
-	dev->hw_features = NETIF_F_SG |
-		NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
-		NETIF_F_TSO | NETIF_F_TSO6;
-	dev->features = dev->hw_features | NETIF_F_RXCSUM;
+	dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_TSO;
+	dev->features = dev->hw_features;
 	SET_ETHTOOL_OPS(dev, &xenvif_ethtool_ops);
 
 	dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
@@ -378,18 +363,16 @@ int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
 		   unsigned long rx_ring_ref, unsigned int tx_evtchn,
 		   unsigned int rx_evtchn)
 {
-	struct task_struct *task;
 	int err = -ENOMEM;
 
-	BUG_ON(vif->tx_irq);
-	BUG_ON(vif->task);
+	/* Already connected through? */
+	if (vif->tx_irq)
+		return 0;
 
 	err = xenvif_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
 	if (err < 0)
 		goto err;
 
-	init_waitqueue_head(&vif->wq);
-
 	if (tx_evtchn == rx_evtchn) {
 		/* feature-split-event-channels == 0 */
 		err = bind_interdomain_evtchn_to_irqhandler(
@@ -422,16 +405,15 @@ int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
 		disable_irq(vif->rx_irq);
 	}
 
-	task = kthread_create(xenvif_kthread,
-			      (void *)vif, "%s", vif->dev->name);
-	if (IS_ERR(task)) {
+	init_waitqueue_head(&vif->wq);
+	vif->task = kthread_create(xenvif_kthread,
+				   (void *)vif, "%s", vif->dev->name);
+	if (IS_ERR(vif->task)) {
 		pr_warn("Could not allocate kthread for %s\n", vif->dev->name);
-		err = PTR_ERR(task);
+		err = PTR_ERR(vif->task);
 		goto err_rx_unbind;
 	}
 
-	vif->task = task;
-
 	rtnl_lock();
 	if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN)
 		dev_set_mtu(vif->dev, ETH_DATA_LEN);
@@ -474,11 +456,6 @@ void xenvif_disconnect(struct xenvif *vif)
 	if (netif_carrier_ok(vif->dev))
 		xenvif_carrier_off(vif);
 
-	if (vif->task) {
-		kthread_stop(vif->task);
-		vif->task = NULL;
-	}
-
 	if (vif->tx_irq) {
 		if (vif->tx_irq == vif->rx_irq)
 			unbind_from_irqhandler(vif->tx_irq, vif);
@@ -489,6 +466,9 @@ void xenvif_disconnect(struct xenvif *vif)
 		vif->tx_irq = 0;
 	}
 
+	if (vif->task)
+		kthread_stop(vif->task);
+
 	xenvif_unmap_frontend_rings(vif);
 }
 
@@ -498,7 +478,6 @@ void xenvif_free(struct xenvif *vif)
 
 	unregister_netdev(vif->dev);
 
-	vfree(vif->grant_copy_op);
 	free_netdev(vif->dev);
 
 	module_put(THIS_MODULE);