drm/amdgpu: make amdgpu_to_sched_priority detect invalid parameters

Returning invalid priorities as _NORMAL is a backwards compatibility
quirk of amdgpu_ctx_ioctl(). Move this detail one layer up where it
belongs.

Signed-off-by: Andres Rodriguez <andresx7@gmail.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c

@@ -232,7 +232,7 @@ static enum amd_sched_priority amdgpu_to_sched_priority(int amdgpu_priority)
 		return AMD_SCHED_PRIORITY_LOW;
 	default:
 		WARN(1, "Invalid context priority %d\n", amdgpu_priority);
-		return AMD_SCHED_PRIORITY_NORMAL;
+		return AMD_SCHED_PRIORITY_INVALID;
 	}
 }
 
@@ -251,8 +251,10 @@ int amdgpu_ctx_ioctl(struct drm_device *dev, void *data,
 	id = args->in.ctx_id;
 	priority = amdgpu_to_sched_priority(args->in.priority);
 
-	if (priority >= AMD_SCHED_PRIORITY_MAX)
-		return -EINVAL;
+	/* For backwards compatibility reasons, we need to accept
+	 * ioctls with garbage in the priority field */
+	if (priority == AMD_SCHED_PRIORITY_INVALID)
+		priority = AMD_SCHED_PRIORITY_NORMAL;
 
 	switch (args->in.op) {
 	case AMDGPU_CTX_OP_ALLOC_CTX:

drivers/gpu/drm/amd/scheduler/gpu_scheduler.h

@@ -120,7 +120,8 @@ enum amd_sched_priority {
 	AMD_SCHED_PRIORITY_HIGH_SW,
 	AMD_SCHED_PRIORITY_HIGH_HW,
 	AMD_SCHED_PRIORITY_KERNEL,
-	AMD_SCHED_PRIORITY_MAX
+	AMD_SCHED_PRIORITY_MAX,
+	AMD_SCHED_PRIORITY_INVALID = -1
 };
 
 /**