drm/radeon: Fix scratch register leak in IB test.

Restructure the code to jump out via labels instead of directly returning
early. Also make error reporting consistent across all hardware generations.
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Simon Kitching <skitching@vonos.net>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/r100.c

@@ -3758,7 +3758,8 @@ int r100_ib_test(struct radeon_device *rdev, struct radeon_ring *ring)
 	WREG32(scratch, 0xCAFEDEAD);
 	r = radeon_ib_get(rdev, RADEON_RING_TYPE_GFX_INDEX, &ib, NULL, 256);
 	if (r) {
-		return r;
+		DRM_ERROR("radeon: failed to get ib (%d).\n", r);
+		goto free_scratch;
 	}
 	ib.ptr[0] = PACKET0(scratch, 0);
 	ib.ptr[1] = 0xDEADBEEF;
@@ -3771,13 +3772,13 @@ int r100_ib_test(struct radeon_device *rdev, struct radeon_ring *ring)
 	ib.length_dw = 8;
 	r = radeon_ib_schedule(rdev, &ib, NULL);
 	if (r) {
-		radeon_scratch_free(rdev, scratch);
-		radeon_ib_free(rdev, &ib);
-		return r;
+		DRM_ERROR("radeon: failed to schedule ib (%d).\n", r);
+		goto free_ib;
 	}
 	r = radeon_fence_wait(ib.fence, false);
 	if (r) {
-		return r;
+		DRM_ERROR("radeon: fence wait failed (%d).\n", r);
+		goto free_ib;
 	}
 	for (i = 0; i < rdev->usec_timeout; i++) {
 		tmp = RREG32(scratch);
@@ -3793,8 +3794,10 @@ int r100_ib_test(struct radeon_device *rdev, struct radeon_ring *ring)
 			  scratch, tmp);
 		r = -EINVAL;
 	}
-	radeon_scratch_free(rdev, scratch);
+free_ib:
 	radeon_ib_free(rdev, &ib);
+free_scratch:
+	radeon_scratch_free(rdev, scratch);
 	return r;
 }
 

drivers/gpu/drm/radeon/r600.c

@@ -2638,7 +2638,7 @@ int r600_ib_test(struct radeon_device *rdev, struct radeon_ring *ring)
 	r = radeon_ib_get(rdev, ring->idx, &ib, NULL, 256);
 	if (r) {
 		DRM_ERROR("radeon: failed to get ib (%d).\n", r);
-		return r;
+		goto free_scratch;
 	}
 	ib.ptr[0] = PACKET3(PACKET3_SET_CONFIG_REG, 1);
 	ib.ptr[1] = ((scratch - PACKET3_SET_CONFIG_REG_OFFSET) >> 2);
@@ -2646,15 +2646,13 @@ int r600_ib_test(struct radeon_device *rdev, struct radeon_ring *ring)
 	ib.length_dw = 3;
 	r = radeon_ib_schedule(rdev, &ib, NULL);
 	if (r) {
-		radeon_scratch_free(rdev, scratch);
-		radeon_ib_free(rdev, &ib);
 		DRM_ERROR("radeon: failed to schedule ib (%d).\n", r);
-		return r;
+		goto free_ib;
 	}
 	r = radeon_fence_wait(ib.fence, false);
 	if (r) {
 		DRM_ERROR("radeon: fence wait failed (%d).\n", r);
-		return r;
+		goto free_ib;
 	}
 	for (i = 0; i < rdev->usec_timeout; i++) {
 		tmp = RREG32(scratch);
@@ -2669,8 +2667,10 @@ int r600_ib_test(struct radeon_device *rdev, struct radeon_ring *ring)
 			  scratch, tmp);
 		r = -EINVAL;
 	}
-	radeon_scratch_free(rdev, scratch);
+free_ib:
 	radeon_ib_free(rdev, &ib);
+free_scratch:
+	radeon_scratch_free(rdev, scratch);
 	return r;
 }