static void backend_disconnect(struct backend_info *be)
{
if (be->vif) {
#ifdef CONFIG_DEBUG_FS
xenvif_debugfs_delif(be->vif);
#endif /* CONFIG_DEBUG_FS */
xenvif_disconnect(be->vif);
}
}
static void disconnect_backend(struct xenbus_device *dev)
{
struct backend_info *be = dev_get_drvdata(&dev->dev);
if (be->vif) {
xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status");
xenvif_disconnect(be->vif);
be->vif = NULL;
}
}
static int netback_remove(struct xenbus_device *dev)
{
struct backend_info *be = dev_get_drvdata(&dev->dev);
unregister_hotplug_status_watch(be);
if (be->vif) {
kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status");
xenvif_disconnect(be->vif);
be->vif = NULL;
}
kfree(be);
dev_set_drvdata(&dev->dev, NULL);
return 0;
}
static void connect(struct backend_info *be)
{
int err;
struct xenbus_device *dev = be->dev;
unsigned long credit_bytes, credit_usec;
unsigned int queue_index;
unsigned int requested_num_queues;
struct xenvif_queue *queue;
/* Check whether the frontend requested multiple queues
* and read the number requested.
*/
err = xenbus_scanf(XBT_NIL, dev->otherend,
"multi-queue-num-queues",
"%u", &requested_num_queues);
if (err < 0) {
requested_num_queues = 1; /* Fall back to single queue */
} else if (requested_num_queues > xenvif_max_queues) {
/* buggy or malicious guest */
xenbus_dev_fatal(dev, err,
"guest requested %u queues, exceeding the maximum of %u.",
requested_num_queues, xenvif_max_queues);
return;
}
err = xen_net_read_mac(dev, be->vif->fe_dev_addr);
if (err) {
xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
return;
}
xen_net_read_rate(dev, &credit_bytes, &credit_usec);
read_xenbus_vif_flags(be);
/* Use the number of queues requested by the frontend */
be->vif->queues = vzalloc(requested_num_queues *
sizeof(struct xenvif_queue));
be->vif->num_queues = requested_num_queues;
be->vif->stalled_queues = requested_num_queues;
for (queue_index = 0; queue_index < requested_num_queues; ++queue_index) {
queue = &be->vif->queues[queue_index];
queue->vif = be->vif;
queue->id = queue_index;
snprintf(queue->name, sizeof(queue->name), "%s-q%u",
be->vif->dev->name, queue->id);
err = xenvif_init_queue(queue);
if (err) {
/* xenvif_init_queue() cleans up after itself on
* failure, but we need to clean up any previously
* initialised queues. Set num_queues to i so that
* earlier queues can be destroyed using the regular
* disconnect logic.
*/
be->vif->num_queues = queue_index;
goto err;
}
queue->remaining_credit = credit_bytes;
err = connect_rings(be, queue);
if (err) {
/* connect_rings() cleans up after itself on failure,
* but we need to clean up after xenvif_init_queue() here,
* and also clean up any previously initialised queues.
*/
xenvif_deinit_queue(queue);
be->vif->num_queues = queue_index;
goto err;
}
}
#ifdef CONFIG_DEBUG_FS
xenvif_debugfs_addif(be->vif);
#endif /* CONFIG_DEBUG_FS */
/* Initialisation completed, tell core driver the number of
* active queues.
*/
rtnl_lock();
netif_set_real_num_tx_queues(be->vif->dev, requested_num_queues);
netif_set_real_num_rx_queues(be->vif->dev, requested_num_queues);
rtnl_unlock();
xenvif_carrier_on(be->vif);
unregister_hotplug_status_watch(be);
err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch,
hotplug_status_changed,
"%s/%s", dev->nodename, "hotplug-status");
if (!err)
be->have_hotplug_status_watch = 1;
netif_tx_wake_all_queues(be->vif->dev);
return;
err:
if (be->vif->num_queues > 0)
xenvif_disconnect(be->vif); /* Clean up existing queues */
vfree(be->vif->queues);
be->vif->queues = NULL;
be->vif->num_queues = 0;
return;
}
static void backend_disconnect(struct backend_info *be)
{
if (be->vif)
xenvif_disconnect(be->vif);
}
