https://bugs.gentoo.org/921370
https://forums.developer.nvidia.com/t/279072
--- a/kernel/conftest.sh
+++ b/kernel/conftest.sh
@@ -4807,6 +4807,11 @@
             CODE="
             #include <drm/drm_gem.h>
+            #if defined(NV_LINUX_IOSYS_MAP_H_PRESENT)
+            typedef struct iosys_map nv_sysio_map_t;
+            #else
+            typedef struct dma_buf_map nv_sysio_map_t;
+            #endif
             int conftest_drm_gem_object_vmap_has_map_arg(
-                    struct drm_gem_object *obj, struct dma_buf_map *map) {
+                    struct drm_gem_object *obj, nv_sysio_map_t *map) {
                 return obj->funcs->vmap(obj, map);
             }"
--- a/kernel-module-source/kernel-open/conftest.sh
+++ b/kernel-module-source/kernel-open/conftest.sh
@@ -4807,6 +4807,11 @@
             CODE="
             #include <drm/drm_gem.h>
+            #if defined(NV_LINUX_IOSYS_MAP_H_PRESENT)
+            typedef struct iosys_map nv_sysio_map_t;
+            #else
+            typedef struct dma_buf_map nv_sysio_map_t;
+            #endif
             int conftest_drm_gem_object_vmap_has_map_arg(
-                    struct drm_gem_object *obj, struct dma_buf_map *map) {
+                    struct drm_gem_object *obj, nv_sysio_map_t *map) {
                 return obj->funcs->vmap(obj, map);
             }"