drm/msm: Return ERR_PTR() from submit_create()

In the next patch, we start having more than a single potential failure
reason.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Acked-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20210728010632.2633470-9-robdclark@gmail.comSigned-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/msm_gem_submit.c

@@ -32,30 +32,27 @@ static struct msm_gem_submit *submit_create(struct drm_device *dev,
 		uint32_t nr_cmds)
 {
 	struct msm_gem_submit *submit;
-	uint64_t sz = struct_size(submit, bos, nr_bos) +
-				  ((u64)nr_cmds * sizeof(submit->cmd[0]));
+	uint64_t sz;
+
+	sz = struct_size(submit, bos, nr_bos) +
+			((u64)nr_cmds * sizeof(submit->cmd[0]));
 
 	if (sz > SIZE_MAX)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
-	submit = kmalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
+	submit = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
 	if (!submit)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	kref_init(&submit->ref);
 	submit->dev = dev;
 	submit->aspace = queue->ctx->aspace;
 	submit->gpu = gpu;
-	submit->fence = NULL;
 	submit->cmd = (void *)&submit->bos[nr_bos];
 	submit->queue = queue;
 	submit->ring = gpu->rb[queue->prio];
 	submit->fault_dumped = false;
 
-	/* initially, until copy_from_user() and bo lookup succeeds: */
-	submit->nr_bos = 0;
-	submit->nr_cmds = 0;
-
 	INIT_LIST_HEAD(&submit->node);
 	INIT_LIST_HEAD(&submit->bo_list);
 
@@ -799,8 +796,8 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 
 	submit = submit_create(dev, gpu, queue, args->nr_bos,
 		args->nr_cmds);
-	if (!submit) {
-		ret = -ENOMEM;
+	if (IS_ERR(submit)) {
+		ret = PTR_ERR(submit);
 		goto out_unlock;
 	}