irqchip/gic-v3-its: Rework LPI freeing

Rework LPI deallocation so that it can be reused by the v4 support
code.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

drivers/irqchip/irq-gic-v3-its.c

@@ -881,16 +881,15 @@ static unsigned long *its_lpi_alloc_chunks(int nr_irqs, int *base, int *nr_ids)
 	return bitmap;
 }
 
-static void its_lpi_free(struct event_lpi_map *map)
+static void its_lpi_free_chunks(unsigned long *bitmap, int base, int nr_ids)
 {
-	int base = map->lpi_base;
-	int nr_ids = map->nr_lpis;
 	int lpi;
 
 	spin_lock(&lpi_lock);
 
 	for (lpi = base; lpi < (base + nr_ids); lpi += IRQS_PER_CHUNK) {
 		int chunk = its_lpi_to_chunk(lpi);
+
 		BUG_ON(chunk > lpi_chunks);
 		if (test_bit(chunk, lpi_bitmap)) {
 			clear_bit(chunk, lpi_bitmap);
@@ -901,8 +900,7 @@ static void its_lpi_free(struct event_lpi_map *map)
 
 	spin_unlock(&lpi_lock);
 
-	kfree(map->lpi_map);
-	kfree(map->col_map);
+	kfree(bitmap);
 }
 
 static struct page *its_allocate_prop_table(gfp_t gfp_flags)
@@ -1674,7 +1672,10 @@ static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq,
 	/* If all interrupts have been freed, start mopping the floor */
 	if (bitmap_empty(its_dev->event_map.lpi_map,
 			 its_dev->event_map.nr_lpis)) {
-		its_lpi_free(&its_dev->event_map);
+		its_lpi_free_chunks(its_dev->event_map.lpi_map,
+				    its_dev->event_map.lpi_base,
+				    its_dev->event_map.nr_lpis);
+		kfree(its_dev->event_map.col_map);
 
 		/* Unmap device/itt */
 		its_send_mapd(its_dev, 0);