d3d11memory: Protect against concurrent access from GPU and CPU to staging texture

Staging texture does not allow GPU access while it's CPU mapped.
But because we cannot block concurrent READ access by GstMemory design,
additional staging texture is still required.

Fixes: https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/1182
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/2375>

diff --git a/subprojects/gst-plugins-bad/gst-libs/gst/d3d11/gstd3d11memory.cpp b/subprojects/gst-plugins-bad/gst-libs/gst/d3d11/gstd3d11memory.cpp
index a0d41e8..21262d1 100644 (file)
--- a/subprojects/gst-plugins-bad/gst-libs/gst/d3d11/gstd3d11memory.cpp
+++ b/subprojects/gst-plugins-bad/gst-libs/gst/d3d11/gstd3d11memory.cpp
@@ -342,7 +342,7 @@ gst_d3d11_memory_upload (GstD3D11Memory * dmem)
   GstD3D11MemoryPrivate *priv = dmem->priv;
   ID3D11DeviceContext *device_context;
 
-  if (!priv->staging || priv->staging == priv->texture ||
+  if (!priv->staging ||
       !GST_MEMORY_FLAG_IS_SET (dmem, GST_D3D11_MEMORY_TRANSFER_NEED_UPLOAD))
     return;
 
@@ -358,7 +358,7 @@ gst_d3d11_memory_download (GstD3D11Memory * dmem)
   GstD3D11MemoryPrivate *priv = dmem->priv;
   ID3D11DeviceContext *device_context;
 
-  if (!priv->staging || priv->staging == priv->texture ||
+  if (!priv->staging ||
       !GST_MEMORY_FLAG_IS_SET (dmem, GST_D3D11_MEMORY_TRANSFER_NEED_DOWNLOAD))
     return;
 
@@ -1433,12 +1433,6 @@ gst_d3d11_allocator_alloc_wrapped (GstD3D11Allocator * self,
   mem->priv->native_type = GST_D3D11_MEMORY_NATIVE_TYPE_TEXTURE_2D;
   mem->device = (GstD3D11Device *) gst_object_ref (device);
 
-  /* This is staging texture as well */
-  if (desc->Usage == D3D11_USAGE_STAGING) {
-    mem->priv->staging = texture;
-    texture->AddRef ();
-  }
-
   return GST_MEMORY_CAST (mem);
 }