diff --git a/drivers/gpu/drm/i915/i915_utils.h b/drivers/gpu/drm/i915/i915_utils.h
index f02f52ab5070..5259edacde38 100644
--- a/drivers/gpu/drm/i915/i915_utils.h
+++ b/drivers/gpu/drm/i915/i915_utils.h
@@ -201,6 +201,11 @@ __check_struct_size(size_t base, size_t arr, size_t count, size_t *size)
 	__T;								\
 })
 
+static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b)
+{
+	return a - b;
+}
+
 /*
  * container_of_user: Extract the superclass from a pointer to a member.
  *
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 8df784a026d2..a29a158990c6 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -146,11 +146,6 @@ static inline void i915_vma_put(struct i915_vma *vma)
 	i915_gem_object_put(vma->obj);
 }
 
-static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b)
-{
-	return a - b;
-}
-
 static inline long
 i915_vma_compare(struct i915_vma *vma,
 		 struct i915_address_space *vm,