[Intel-gfx] [PATCH v5 05/11] drm/i915: tidy initialisation failure paths (legacy, part 1)

[Dave Gordon]

Make sure intel_unpin_ringbuffer_obj() can handle the case where the
ringbuffer has been allocated but map-and-pin failed. Return early if
the ringbuffer isn't mapped [Chris Wilson].

That allows us to simplify the cleanup path in intel_init_ring_buffer(),
as it can just take the error exit and let intel_cleanup_ring_buffer()
deal with any partially-set-up state.

Signed-off-by: Dave Gordon <david.s.gordon at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/intel_ringbuffer.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 6f5b511..3e1aec8 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -2055,6 +2055,9 @@ static int init_phys_status_page(struct intel_engine_cs *ring)
 
 void intel_unpin_ringbuffer_obj(struct intel_ringbuffer *ringbuf)
 {
+	if (!ringbuf->virtual_start)
+		return;
+
 	if (HAS_LLC(ringbuf->obj->base.dev) && !ringbuf->obj->stolen)
 		vunmap(ringbuf->virtual_start);
 	else
@@ -2232,6 +2235,13 @@ static int intel_init_ring_buffer(struct drm_device *dev,
 	}
 	ring->buffer = ringbuf;
 
+	ret = intel_pin_and_map_ringbuffer_obj(dev, ringbuf);
+	if (ret) {
+		DRM_ERROR("Failed to pin and map ringbuffer %s: %d\n",
+				ring->name, ret);
+		goto error;
+	}
+
 	if (I915_NEED_GFX_HWS(dev)) {
 		ret = init_status_page(ring);
 		if (ret)
@@ -2243,14 +2253,6 @@ static int intel_init_ring_buffer(struct drm_device *dev,
 			goto error;
 	}
 
-	ret = intel_pin_and_map_ringbuffer_obj(dev, ringbuf);
-	if (ret) {
-		DRM_ERROR("Failed to pin and map ringbuffer %s: %d\n",
-				ring->name, ret);
-		intel_destroy_ringbuffer_obj(ringbuf);
-		goto error;
-	}
-
 	ret = i915_cmd_parser_init_ring(ring);
 	if (ret)
 		goto error;
-- 
1.9.1