[RFC PATCH v1 03/16] drm/nouveau: add reservation to nouveau_gem_ioctl_cpu_prep

Maarten Lankhorst
2014-05-14T14:57:42Z

Apart from some code inside ttm itself and nouveau_bo_vma_del,
this is the only place where ttm_bo_wait is used without a reservation.
Fix this so we can remove the fence_lock later on.

After the switch to rcu the reservation lock will be
removed again.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
---
drivers/gpu/drm/nouveau/nouveau_gem.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c
index c90c0dc0afe8..6e1c58a880fe 100644
--- a/drivers/gpu/drm/nouveau/nouveau_gem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
@@ -886,17 +886,31 @@ nouveau_gem_ioctl_cpu_prep(struct drm_device *dev, void *data,
struct drm_gem_object *gem;
struct nouveau_bo *nvbo;
bool no_wait = !!(req->flags & NOUVEAU_GEM_CPU_PREP_NOWAIT);
- int ret = -EINVAL;
+ int ret;
+ struct nouveau_fence *fence = NULL;

gem = drm_gem_object_lookup(dev, file_priv, req->handle);
if (!gem)
return -ENOENT;
nvbo = nouveau_gem_object(gem);

- spin_lock(&nvbo->bo.bdev->fence_lock);
- ret = ttm_bo_wait(&nvbo->bo, true, true, no_wait);
- spin_unlock(&nvbo->bo.bdev->fence_lock);
+ ret = ttm_bo_reserve(&nvbo->bo, true, false, false, 0);
+ if (!ret) {
+ spin_lock(&nvbo->bo.bdev->fence_lock);
+ ret = ttm_bo_wait(&nvbo->bo, true, true, true);
+ if (!no_wait && ret)
+ fence = nouveau_fence_ref(nvbo->bo.sync_obj);
+ spin_unlock(&nvbo->bo.bdev->fence_lock);
+
+ ttm_bo_unreserve(&nvbo->bo);
+ }
drm_gem_object_unreference_unlocked(gem);
+
+ if (fence) {
+ ret = nouveau_fence_wait(fence, true, no_wait);
+ nouveau_fence_unref(&fence);
+ }
+
return ret;
}