iommu/vt-d: Switch to bitmap_zalloc()

Switch to bitmap_zalloc() to show clearly what we are allocating.
Besides that it returns pointer of bitmap type instead of opaque void *.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel_irq_remapping.c

@@ -548,8 +548,7 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 		goto out_free_table;
 	}
 
-	bitmap = kcalloc(BITS_TO_LONGS(INTR_REMAP_TABLE_ENTRIES),
-			 sizeof(long), GFP_ATOMIC);
+	bitmap = bitmap_zalloc(INTR_REMAP_TABLE_ENTRIES, GFP_ATOMIC);
 	if (bitmap == NULL) {
 		pr_err("IR%d: failed to allocate bitmap\n", iommu->seq_id);
 		goto out_free_pages;
@@ -616,7 +615,7 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 	return 0;
 
 out_free_bitmap:
-	kfree(bitmap);
+	bitmap_free(bitmap);
 out_free_pages:
 	__free_pages(pages, INTR_REMAP_PAGE_ORDER);
 out_free_table:
@@ -640,7 +639,7 @@ static void intel_teardown_irq_remapping(struct intel_iommu *iommu)
 		}
 		free_pages((unsigned long)iommu->ir_table->base,
 			   INTR_REMAP_PAGE_ORDER);
-		kfree(iommu->ir_table->bitmap);
+		bitmap_free(iommu->ir_table->bitmap);
 		kfree(iommu->ir_table);
 		iommu->ir_table = NULL;
 	}