drm/v3d: Clean up the reservation object setup.

The extra to_v3d_bo() calls came from copying this from the vc4
driver, which stored the cma gem object in the structs.

v2: Fix an unused var warning
Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20181108161654.19888-4-eric@anholt.net
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com> (v1)

drivers/gpu/drm/v3d/v3d_gem.c

@@ -210,14 +210,11 @@ static void
 v3d_attach_object_fences(struct v3d_exec_info *exec)
 {
 	struct dma_fence *out_fence = exec->render_done_fence;
-	struct v3d_bo *bo;
 	int i;
 
 	for (i = 0; i < exec->bo_count; i++) {
-		bo = to_v3d_bo(&exec->bo[i]->base);
-
 		/* XXX: Use shared fences for read-only objects. */
-		reservation_object_add_excl_fence(bo->resv, out_fence);
+		reservation_object_add_excl_fence(exec->bo[i]->resv, out_fence);
 	}
 }
 
@@ -228,11 +225,8 @@ v3d_unlock_bo_reservations(struct drm_device *dev,
 {
 	int i;
 
-	for (i = 0; i < exec->bo_count; i++) {
-		struct v3d_bo *bo = to_v3d_bo(&exec->bo[i]->base);
-
-		ww_mutex_unlock(&bo->resv->lock);
-	}
+	for (i = 0; i < exec->bo_count; i++)
+		ww_mutex_unlock(&exec->bo[i]->resv->lock);
 
 	ww_acquire_fini(acquire_ctx);
 }
@@ -251,13 +245,13 @@ v3d_lock_bo_reservations(struct drm_device *dev,
 {
 	int contended_lock = -1;
 	int i, ret;
-	struct v3d_bo *bo;
 
 	ww_acquire_init(acquire_ctx, &reservation_ww_class);
 
 retry:
 	if (contended_lock != -1) {
-		bo = to_v3d_bo(&exec->bo[contended_lock]->base);
+		struct v3d_bo *bo = exec->bo[contended_lock];
+
 		ret = ww_mutex_lock_slow_interruptible(&bo->resv->lock,
 						       acquire_ctx);
 		if (ret) {
@@ -270,19 +264,16 @@ v3d_lock_bo_reservations(struct drm_device *dev,
 		if (i == contended_lock)
 			continue;
 
-		bo = to_v3d_bo(&exec->bo[i]->base);
-
-		ret = ww_mutex_lock_interruptible(&bo->resv->lock, acquire_ctx);
+		ret = ww_mutex_lock_interruptible(&exec->bo[i]->resv->lock,
+						  acquire_ctx);
 		if (ret) {
 			int j;
 
-			for (j = 0; j < i; j++) {
-				bo = to_v3d_bo(&exec->bo[j]->base);
-				ww_mutex_unlock(&bo->resv->lock);
-			}
+			for (j = 0; j < i; j++)
+				ww_mutex_unlock(&exec->bo[j]->resv->lock);
 
 			if (contended_lock != -1 && contended_lock >= i) {
-				bo = to_v3d_bo(&exec->bo[contended_lock]->base);
+				struct v3d_bo *bo = exec->bo[contended_lock];
 
 				ww_mutex_unlock(&bo->resv->lock);
 			}
@@ -303,9 +294,7 @@ v3d_lock_bo_reservations(struct drm_device *dev,
 	 * before we commit the CL to the hardware.
 	 */
 	for (i = 0; i < exec->bo_count; i++) {
-		bo = to_v3d_bo(&exec->bo[i]->base);
-
-		ret = reservation_object_reserve_shared(bo->resv, 1);
+		ret = reservation_object_reserve_shared(exec->bo[i]->resv, 1);
 		if (ret) {
 			v3d_unlock_bo_reservations(dev, exec, acquire_ctx);
 			return ret;