diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index a47b985..66741ab0 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -145,7 +145,8 @@ extern struct vfio_info_cap_header *vfio_info_cap_add(
 extern void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
 
 extern int vfio_info_add_capability(struct vfio_info_cap *caps,
-				    int cap_type_id, void *cap_type);
+				    struct vfio_info_cap_header *cap,
+				    size_t size);
 
 extern int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr,
 					      int num_irqs, int max_irq_type,