xen: remove irq bindcount

There should be no need for us to maintain our own bind count for
irqs, since the surrounding irq system should keep track of shared
irqs for us.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 0541e07..459121c5 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -54,7 +54,7 @@
 
 /* Interrupt types. */
 enum xen_irq_type {
-	IRQT_UNBOUND,
+	IRQT_UNBOUND = 0,
 	IRQT_PIRQ,
 	IRQT_VIRQ,
 	IRQT_IPI,
@@ -102,9 +102,6 @@
 	return cpu_evtchn_mask_p[cpu].bits;
 }
 
-/* Reference counts for bindings to IRQs. */
-static int irq_bindcount[NR_IRQS];
-
 /* Xen will never allocate port zero for any purpose. */
 #define VALID_EVTCHN(chn)	((chn) != 0)
 
@@ -330,9 +327,8 @@
 	int irq;
 	struct irq_desc *desc;
 
-	/* Only allocate from dynirq range */
 	for (irq = 0; irq < nr_irqs; irq++)
-		if (irq_bindcount[irq] == 0)
+		if (irq_info[irq].type == IRQT_UNBOUND)
 			break;
 
 	if (irq == nr_irqs)
@@ -365,8 +361,6 @@
 		irq_info[irq] = mk_evtchn_info(evtchn);
 	}
 
-	irq_bindcount[irq]++;
-
 	spin_unlock(&irq_mapping_update_lock);
 
 	return irq;
@@ -403,8 +397,6 @@
 		bind_evtchn_to_cpu(evtchn, cpu);
 	}
 
-	irq_bindcount[irq]++;
-
  out:
 	spin_unlock(&irq_mapping_update_lock);
 	return irq;
@@ -441,8 +433,6 @@
 		bind_evtchn_to_cpu(evtchn, cpu);
 	}
 
-	irq_bindcount[irq]++;
-
 	spin_unlock(&irq_mapping_update_lock);
 
 	return irq;
@@ -455,7 +445,7 @@
 
 	spin_lock(&irq_mapping_update_lock);
 
-	if ((--irq_bindcount[irq] == 0) && VALID_EVTCHN(evtchn)) {
+	if (VALID_EVTCHN(evtchn)) {
 		close.port = evtchn;
 		if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
 			BUG();
@@ -681,6 +671,8 @@
 /* Rebind a new event channel to an existing irq. */
 void rebind_evtchn_irq(int evtchn, int irq)
 {
+	struct irq_info *info = info_for_irq(irq);
+
 	/* Make sure the irq is masked, since the new event channel
 	   will also be masked. */
 	disable_irq(irq);
@@ -690,8 +682,8 @@
 	/* After resume the irq<->evtchn mappings are all cleared out */
 	BUG_ON(evtchn_to_irq[evtchn] != -1);
 	/* Expect irq to have been bound before,
-	   so the bindcount should be non-0 */
-	BUG_ON(irq_bindcount[irq] == 0);
+	   so there should be a proper type */
+	BUG_ON(info->type == IRQT_UNBOUND);
 
 	evtchn_to_irq[evtchn] = irq;
 	irq_info[irq] = mk_evtchn_info(evtchn);
@@ -948,9 +940,5 @@
 	for (i = 0; i < NR_EVENT_CHANNELS; i++)
 		mask_evtchn(i);
 
-	/* Dynamic IRQ space is currently unbound. Zero the refcnts. */
-	for (i = 0; i < nr_irqs; i++)
-		irq_bindcount[i] = 0;
-
 	irq_ctx_init(smp_processor_id());
 }