xen/evtchn: support more than 4096 ports

Remove the check during unbind for NR_EVENT_CHANNELS as this limits
support to less than 4096 ports.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index c6d64f1e191c..9d0d88cf74af 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -952,6 +952,19 @@ static int find_virq(unsigned int virq, unsigned int cpu)
         return rc;
 }
 
+/**
+ * xen_evtchn_nr_channels - number of usable event channel ports
+ *
+ * This may be less than the maximum supported by the current
+ * hypervisor ABI. Use xen_evtchn_max_channels() for the maximum
+ * supported.
+ */
+unsigned xen_evtchn_nr_channels(void)
+{
+        return evtchn_ops->nr_channels();
+}
+EXPORT_SYMBOL_GPL(xen_evtchn_nr_channels);
+
 int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
 {
         struct evtchn_bind_virq bind_virq;