[PATCH 6/6] drm/msm: Do priority checking during submitqueue create

[Jordan Crouse <jcrouse@codeaurora.org>]

Now that the priority must be set in the submitqueue we can check
at create time that the requested priority is valid.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
---
 drivers/gpu/drm/msm/msm_gem_submit.c  |  8 +++++---
 drivers/gpu/drm/msm/msm_submitqueue.c | 25 +++++++++++++++++++------
 2 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index 47a9e87..5b9210b 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -421,7 +421,7 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 	struct msm_gpu_submitqueue *queue;
 	int out_fence_fd = -1;
 	unsigned i;
-	int ret, ring;
+	int ret;
 
 	if (!gpu)
 		return -ENXIO;
@@ -439,6 +439,9 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 	if (!queue)
 		return -ENOENT;
 
+	if (queue->prio >= gpu->nr_rings)
+		return -EINVAL;
+
 	if (args->flags & MSM_SUBMIT_FENCE_FD_IN) {
 		in_fence = sync_file_get_fence(args->fence_fd);
 
@@ -545,8 +548,7 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 
 	submit->nr_cmds = i;
 
-	ring = clamp_t(uint32_t, queue->prio, 0, gpu->nr_rings - 1);
-	submit->ring = gpu->rb[ring];
+	submit->ring = gpu->rb[queue->prio];
 
 	submit->fence = msm_fence_alloc(queue->fctx);
 	if (IS_ERR(submit->fence)) {
diff --git a/drivers/gpu/drm/msm/msm_submitqueue.c b/drivers/gpu/drm/msm/msm_submitqueue.c
index f23b43e..da4bee8 100644
--- a/drivers/gpu/drm/msm/msm_submitqueue.c
+++ b/drivers/gpu/drm/msm/msm_submitqueue.c
@@ -64,6 +64,7 @@ void msm_submitqueue_close(struct msm_file_private *ctx)
 int msm_submitqueue_create(struct drm_device *drm, struct msm_file_private *ctx,
 		u32 prio, u32 flags, u32 *id)
 {
+	struct msm_drm_private *priv = drm->dev_private;
 	struct msm_gpu_submitqueue *queue;
 	char name[32];
 	int ret = 0;
@@ -77,7 +78,13 @@ int msm_submitqueue_create(struct drm_device *drm, struct msm_file_private *ctx,
 
 	kref_init(&queue->ref);
 	queue->flags = flags;
-	queue->prio = prio;
+
+	if (priv->gpu) {
+		if (prio >= priv->gpu->nr_rings)
+			return -EINVAL;
+
+		queue->prio = prio;
+	}
 
 	write_lock(&ctx->queuelock);
 
@@ -114,18 +121,24 @@ int msm_submitqueue_create(struct drm_device *drm, struct msm_file_private *ctx,
 
 int msm_submitqueue_init(struct drm_device *drm, struct msm_file_private *ctx)
 {
+	struct msm_drm_private *priv = drm->dev_private;
+	int default_prio;
+
 	if (!ctx)
 		return 0;
 
+	/*
+	 * Select priority 2 as the "default priority" unless nr_rings is less
+	 * than 2 and then pick the lowest pirority
+	 */
+	default_prio = priv->gpu ?
+		clamp_t(uint32_t, 2, 0, priv->gpu->nr_rings - 1) : 0;
+
 	INIT_LIST_HEAD(&ctx->submitqueues);
 
 	rwlock_init(&ctx->queuelock);
 
-	/*
-	 * Add the "default" submitqueue with id 0
-	 * "low" priority (2) and no flags
-	 */
-	return msm_submitqueue_create(drm, ctx, 2, 0, NULL);
+	return msm_submitqueue_create(drm, ctx, default_prio, 0, NULL);
 }
 
 int msm_submitqueue_remove(struct msm_file_private *ctx, u32 id)
-- 
1.9.1