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 ||
vif->dealloc_task == NULL ||
!xenvif_schedulable(vif))
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;
/* If the skb is GSO then we'll also need an extra slot for the
* metadata.
*/
if (skb_is_gso(skb))
min_slots_needed++;
/* 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)) {
vif->wake_queue.function = xenvif_wake_queue;
vif->wake_queue.data = (unsigned long)vif;
xenvif_stop_queue(vif);
mod_timer(&vif->wake_queue,
jiffies + rx_drain_timeout_jiffies);
}
skb_queue_tail(&vif->rx_queue, skb);
xenvif_kick_thread(vif);
return NETDEV_TX_OK;
drop:
vif->dev->stats.tx_dropped++;
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct xenvif *vif = netdev_priv(dev);
struct xenvif_queue *queue = NULL;
unsigned int num_queues = vif->num_queues;
u16 index;
int min_slots_needed;
BUG_ON(skb->dev != dev);
/* Drop the packet if queues are not set up */
if (num_queues < 1)
goto drop;
/* Obtain the queue to be used to transmit this packet */
index = skb_get_queue_mapping(skb);
if (index >= num_queues) {
pr_warn_ratelimited("Invalid queue %hu for packet on interface %s\n.",
index, vif->dev->name);
index %= num_queues;
}
queue = &vif->queues[index];
/* Drop the packet if queue is not ready */
if (queue->task == NULL ||
queue->dealloc_task == NULL ||
!xenvif_schedulable(vif))
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;
/* If the skb is GSO then we'll also need an extra slot for the
* metadata.
*/
if (skb_is_gso(skb))
min_slots_needed++;
/* 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(queue, min_slots_needed)) {
queue->rx_stalled.function = xenvif_rx_stalled;
queue->rx_stalled.data = (unsigned long)queue;
xenvif_stop_queue(queue);
mod_timer(&queue->rx_stalled,
jiffies + rx_drain_timeout_jiffies);
}
skb_queue_tail(&queue->rx_queue, skb);
xenvif_kick_thread(queue);
return NETDEV_TX_OK;
drop:
vif->dev->stats.tx_dropped++;
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
