drm/nouveau: use rcu in nouveau_gem_ioctl_cpu_prep

With the conversion to the reservation api this should be safe.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 12 insertions, 16 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c
index a28b5102c4a5..4120289ff53e 100644
--- a/drivers/gpu/drm/nouveau/nouveau_gem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
@@ -861,33 +861,29 @@ 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);
+        bool write = !!(req->flags & NOUVEAU_GEM_CPU_PREP_WRITE);
         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);
 
-        ret = ttm_bo_reserve(&nvbo->bo, true, false, false, NULL);
-        if (!ret) {
-                ret = ttm_bo_wait(&nvbo->bo, true, true, true);
-                if (!no_wait && ret) {
-                        struct fence *excl;
-
-                        excl = reservation_object_get_excl(nvbo->bo.resv);
-                        fence = nouveau_fence_ref((struct nouveau_fence *)excl);
-                }
+        if (no_wait)
+                ret = reservation_object_test_signaled_rcu(nvbo->bo.resv, write) ? 0 : -EBUSY;
+        else {
+                long lret;
 
-                ttm_bo_unreserve(&nvbo->bo);
+                lret = reservation_object_wait_timeout_rcu(nvbo->bo.resv, write, true, 30 * HZ);
+                if (!lret)
+                        ret = -EBUSY;
+                else if (lret > 0)
+                        ret = 0;
+                else
+                        ret = lret;
         }
         drm_gem_object_unreference_unlocked(gem);
 
-        if (fence) {
-                ret = nouveau_fence_wait(fence, true, no_wait);
-                nouveau_fence_unref(&fence);
-        }
-
         return ret;
 }