drm/etnaviv: simplify submit_create

Use kzalloc so other code doesn't need to worry about uninitialized members.
Drop the non-standard GFP flags, as we really don't want to fail the submit
when under slight memory pressure. Remove one level of indentation by using
an early return if the allocation failed. Also remove the unused drm device
member.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>

drivers/gpu/drm/etnaviv/etnaviv_gem.h

@@ -101,7 +101,6 @@ struct etnaviv_gem_submit_bo {
  * lasts for the duration of the submit-ioctl.
  */
 struct etnaviv_gem_submit {
-	struct drm_device *dev;
 	struct etnaviv_gpu *gpu;
 	struct ww_acquire_ctx ticket;
 	struct dma_fence *fence;

drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c

@@ -38,17 +38,13 @@ static struct etnaviv_gem_submit *submit_create(struct drm_device *dev,
 	struct etnaviv_gem_submit *submit;
 	size_t sz = size_vstruct(nr, sizeof(submit->bos[0]), sizeof(*submit));
 
-	submit = kmalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
-	if (submit) {
-		submit->dev = dev;
-		submit->gpu = gpu;
+	submit = kzalloc(sz, GFP_KERNEL);
+	if (!submit)
+		return NULL;
 
-		/* initially, until copy_from_user() and bo lookup succeeds: */
-		submit->nr_bos = 0;
-		submit->fence = NULL;
+	submit->gpu = gpu;
 
 	ww_acquire_init(&submit->ticket, &reservation_ww_class);
-	}
 
 	return submit;
 }