Commit 35b62a89 authored by Chris Wilson's avatar Chris Wilson
Browse files

drm/i915: Skip pread/pwrite if size to copy is 0. 



Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
parent df6d075a

drivers/gpu/drm/i915/i915_gem.c

+13 −7
Original line number Diff line number Diff line
@@ -576,7 +576,7 @@ i915_gem_pread_ioctl(struct drm_device *dev, void *data, 
	struct drm_i915_gem_pread *args = data;

	struct drm_gem_object *obj;

	struct drm_i915_gem_object *obj_priv;

	int ret;

	int ret = 0;



	obj = drm_gem_object_lookup(dev, file_priv, args->handle);

	if (obj == NULL)
@@ -586,14 +586,17 @@ i915_gem_pread_ioctl(struct drm_device *dev, void *data, 
	/* Bounds check source.  */

	if (args->offset > obj->size || args->size > obj->size - args->offset) {

		ret = -EINVAL;

		goto err;

		goto out;

	}



	if (args->size == 0)

		goto out;



	if (!access_ok(VERIFY_WRITE,

		       (char __user *)(uintptr_t)args->data_ptr,

		       args->size)) {

		ret = -EFAULT;

		goto err;

		goto out;

	}



	if (i915_gem_object_needs_bit17_swizzle(obj)) {
@@ -605,7 +608,7 @@ i915_gem_pread_ioctl(struct drm_device *dev, void *data, 
							file_priv);

	}



err:

out:

	drm_gem_object_unreference_unlocked(obj);

	return ret;

}
@@ -1059,14 +1062,17 @@ i915_gem_pwrite_ioctl(struct drm_device *dev, void *data, 
	/* Bounds check destination. */

	if (args->offset > obj->size || args->size > obj->size - args->offset) {

		ret = -EINVAL;

		goto err;

		goto out;

	}



	if (args->size == 0)

		goto out;



	if (!access_ok(VERIFY_READ,

		       (char __user *)(uintptr_t)args->data_ptr,

		       args->size)) {

		ret = -EFAULT;

		goto err;

		goto out;

	}



	/* We can only do the GTT pwrite on untiled buffers, as otherwise
@@ -1100,7 +1106,7 @@ i915_gem_pwrite_ioctl(struct drm_device *dev, void *data, 
		DRM_INFO("pwrite failed %d\n", ret);

#endif



err:

out:

	drm_gem_object_unreference_unlocked(obj);

	return ret;

}