pci: intr-remap: Free irte memory if SPARSE_IRQ=y

With SPARSE_IRQ=y the irte descriptors are dynamically allocated, but not
freed in free_irte().

That was ok as long as the sparse irq core was not freeing irq descriptors on
destroy_irq(). Now we leak the irte descriptor. Free it in free_irte().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/intr_remapping.c

@@ -95,6 +95,15 @@ static struct irq_2_iommu *irq_2_iommu_alloc(unsigned int irq)
 	return desc->irq_2_iommu;
 }
 
+static void irq_2_iommu_free(unsigned int irq)
+{
+	struct irq_data *d = irq_get_irq_data(irq);
+	struct irq_2_iommu *p = d->irq_2_iommu;
+
+	d->irq_2_iommu = NULL;
+	kfree(p);
+}
+
 #else /* !CONFIG_SPARSE_IRQ */
 
 static struct irq_2_iommu irq_2_iommuX[NR_IRQS];
@@ -110,6 +119,9 @@ static struct irq_2_iommu *irq_2_iommu_alloc(unsigned int irq)
 {
 	return irq_2_iommu(irq);
 }
+
+static void irq_2_iommu_free(unsigned int irq) { }
+
 #endif
 
 static DEFINE_SPINLOCK(irq_2_ir_lock);
@@ -440,6 +452,8 @@ int free_irte(int irq)
 
 	spin_unlock_irqrestore(&irq_2_ir_lock, flags);
 
+	irq_2_iommu_free(irq);
+
 	return rc;
 }