[RFT 2/5] drm/msm/gem: dma_map/unmap_sgtable()

[Rob Clark <robin.clark@oss.qualcomm.com>]

This should functionally be a no-op for us, since we are managing our
SMMU directly (dma_map_ops is NULL), but it populates the dma_len/
dma_address's so that we can use them for setting up pgtable mappings.

Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/msm_gem.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 181b9ad32672..72e3cd8bb1e7 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -219,6 +219,15 @@ static struct page **get_pages(struct drm_gem_object *obj)
 			goto error;
 		}
 
+		ret = dma_map_sgtable(drm_dev_dma_dev(obj->dev),
+				      msm_obj->sgt,
+				      DMA_BIDIRECTIONAL,
+				      DMA_ATTR_SKIP_CPU_SYNC);
+		if (ret) {
+			DRM_DEV_ERROR(dev->dev, "could not map sgtable: %d\n", ret);
+			goto error;
+		}
+
 		update_device_mem(dev->dev_private, obj->size);
 
 		/* For non-cached buffers, ensure the new pages are clean
@@ -233,6 +242,8 @@ static struct page **get_pages(struct drm_gem_object *obj)
 	return msm_obj->pages;
 
 error:
+	if (!IS_ERR(msm_obj->sgt))
+		drm_prime_gem_destroy(obj, msm_obj->sgt);
 	msm_obj->sgt = NULL;
 
 	drm_gem_put_pages(obj, msm_obj->pages, false, false);
@@ -260,6 +271,11 @@ static void put_pages(struct drm_gem_object *obj)
 		if (msm_obj->flags & MSM_BO_WC)
 			sync_for_cpu(msm_obj);
 
+		dma_unmap_sgtable(drm_dev_dma_dev(obj->dev),
+				  msm_obj->sgt,
+				  DMA_BIDIRECTIONAL,
+				  DMA_ATTR_SKIP_CPU_SYNC);
+
 		sg_free_table(msm_obj->sgt);
 		kfree(msm_obj->sgt);
 		msm_obj->sgt = NULL;
-- 
2.55.0