[PATCH 1/2] drm/i915: Check whether the ring is initialised prior to dispatch

[chris at chris-wilson.co.uk (Chris Wilson)]

Rather than use the magic feature tests HAS_BLT/HAS_BSD just check
whether the ring we are about to dispatch the execbuffer on is
initialised.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |   13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 21fc11d..932e82b 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1064,17 +1064,9 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
 		ring = &dev_priv->ring[RCS];
 		break;
 	case I915_EXEC_BSD:
-		if (!HAS_BSD(dev)) {
-			DRM_DEBUG("execbuf with invalid ring (BSD)\n");
-			return -EINVAL;
-		}
 		ring = &dev_priv->ring[VCS];
 		break;
 	case I915_EXEC_BLT:
-		if (!HAS_BLT(dev)) {
-			DRM_DEBUG("execbuf with invalid ring (BLT)\n");
-			return -EINVAL;
-		}
 		ring = &dev_priv->ring[BCS];
 		break;
 	default:
@@ -1082,6 +1074,11 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
 			  (int)(args->flags & I915_EXEC_RING_MASK));
 		return -EINVAL;
 	}
+	if (!ring->obj) {
+		DRM_DEBUG("execbuf with invalid ring: %d\n",
+			  (int)(args->flags & I915_EXEC_RING_MASK));
+		return -EINVAL;
+	}
 
 	mode = args->flags & I915_EXEC_CONSTANTS_MASK;
 	mask = I915_EXEC_CONSTANTS_MASK;
-- 
1.7.10