drm/vmwgfx: Fix setting of dma masks

BugLink: https://bugs.launchpad.net/bugs/1818813

commit 4cbfa1e6 upstream.

Previously we set only the dma mask and not the coherent mask. Fix that.
Also, for clarity, make sure both are initially set to 64 bits.

Cc: <stable@vger.kernel.org>
Fixes: 0d00c488: ("drm/vmwgfx: Fix the driver for large dma addresses")
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Deepak Rawat <drawat@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

drivers/gpu/drm/vmwgfx/vmwgfx_drv.c

@@ -594,13 +594,16 @@ static int vmw_dma_select_mode(struct vmw_private *dev_priv)
 static int vmw_dma_masks(struct vmw_private *dev_priv)
 {
 	struct drm_device *dev = dev_priv->dev;
+	int ret = 0;
 
-	if (intel_iommu_enabled &&
+	ret = dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64));
+	if (dev_priv->map_mode != vmw_dma_phys &&
 	    (sizeof(unsigned long) == 4 || vmw_restrict_dma_mask)) {
 		DRM_INFO("Restricting DMA addresses to 44 bits.\n");
-		return dma_set_mask(dev->dev, DMA_BIT_MASK(44));
+		return dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(44));
 	}
-	return 0;
+
+	return ret;
 }
 #else
 static int vmw_dma_masks(struct vmw_private *dev_priv)