+static struct i915_vma *
+shadow_batch_pin(struct i915_execbuffer *eb, struct drm_i915_gem_object *obj)
+{
+ struct drm_i915_private *dev_priv = eb->i915;
+ struct i915_vma * const vma = *eb->vma;
+ struct i915_address_space *vm;
+ u64 flags;
+
+ /*
+ * PPGTT backed shadow buffers must be mapped RO, to prevent
+ * post-scan tampering
+ */
+ if (CMDPARSER_USES_GGTT(dev_priv)) {
+ flags = PIN_GLOBAL;
+ vm = &dev_priv->ggtt.vm;
+ eb->batch_flags |= I915_DISPATCH_SECURE;
+ } else if (vma->vm->has_read_only) {
+ flags = PIN_USER;
+ vm = vma->vm;
+ i915_gem_object_set_readonly(obj);
+ } else {
+ DRM_DEBUG("Cannot prevent post-scan tampering without RO capable vm\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ return i915_gem_object_pin(obj, vm, NULL, 0, 0, flags);
+}
+