[PATCH 1/3] drm: Balance error path for GEM handle allocation

Chris Wilson
2016-01-04T10:10:59Z

The current error path for failure when establishing a handle for a GEM
object is unbalance, e.g. we call object_close() without calling first
object_open(). Use the typical onion structure to only undo what has
been set up prior to the error.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
drivers/gpu/drm/drm_gem.c | 29 +++++++++++++++++------------
1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 2e10bba4468b..a08176debc0e 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -343,27 +343,32 @@ drm_gem_handle_create_tail(struct drm_file *file_priv,
spin_unlock(&file_priv->table_lock);
idr_preload_end();
mutex_unlock(&dev->object_name_lock);
- if (ret < 0) {
- drm_gem_object_handle_unreference_unlocked(obj);
- return ret;
- }
+ if (ret < 0)
+ goto err_unref;
+
*handlep = ret;

ret = drm_vma_node_allow(&obj->vma_node, file_priv->filp);
- if (ret) {
- drm_gem_handle_delete(file_priv, *handlep);
- return ret;
- }
+ if (ret)
+ goto err_remove;

if (dev->driver->gem_open_object) {
ret = dev->driver->gem_open_object(obj, file_priv);
- if (ret) {
- drm_gem_handle_delete(file_priv, *handlep);
- return ret;
- }
+ if (ret)
+ goto err_revoke;
}

return 0;
+
+err_revoke:
+ drm_vma_node_revoke(&obj->vma_node, file_priv->filp);
+err_remove:
+ spin_lock(&file_priv->table_lock);
+ idr_remove(&file_priv->object_idr, *handlep);
+ spin_unlock(&file_priv->table_lock);
+err_unref:
+ drm_gem_object_handle_unreference_unlocked(obj);
+ return ret;
}

/**
--
2.6.4