diff --git a/include/private/gui/LayerState.h b/include/private/gui/LayerState.h
new file mode 100644
index 0000000..ca277e0
--- /dev/null
+++ b/include/private/gui/LayerState.h
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_SF_LAYER_STATE_H
+#define ANDROID_SF_LAYER_STATE_H
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#include <utils/Errors.h>
+
+#include <ui/Region.h>
+#include <gui/ISurface.h>
+
+namespace android {
+
+class Parcel;
+class ISurfaceComposerClient;
+
+struct layer_state_t {
+
+    layer_state_t()
+        :   surface(0), what(0),
+            x(0), y(0), z(0), w(0), h(0),
+            alpha(0), tint(0), flags(0), mask(0),
+            reserved(0)
+    {
+        matrix.dsdx = matrix.dtdy = 1.0f;
+        matrix.dsdy = matrix.dtdx = 0.0f;
+    }
+
+    status_t    write(Parcel& output) const;
+    status_t    read(const Parcel& input);
+
+            struct matrix22_t {
+                float   dsdx;
+                float   dtdx;
+                float   dsdy;
+                float   dtdy;
+            };
+            SurfaceID       surface;
+            uint32_t        what;
+            float           x;
+            float           y;
+            uint32_t        z;
+            uint32_t        w;
+            uint32_t        h;
+            float           alpha;
+            uint32_t        tint;
+            uint8_t         flags;
+            uint8_t         mask;
+            uint8_t         reserved;
+            matrix22_t      matrix;
+            // non POD must be last. see write/read
+            Region          transparentRegion;
+};
+
+struct ComposerState {
+    sp<ISurfaceComposerClient> client;
+    layer_state_t state;
+    status_t    write(Parcel& output) const;
+    status_t    read(const Parcel& input);
+};
+
+}; // namespace android
+
+#endif // ANDROID_SF_LAYER_STATE_H
+
diff --git a/include/private/gui/SharedBufferStack.h b/include/private/gui/SharedBufferStack.h
new file mode 100644
index 0000000..0da03d1
--- /dev/null
+++ b/include/private/gui/SharedBufferStack.h
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_SF_SHARED_BUFFER_STACK_H
+#define ANDROID_SF_SHARED_BUFFER_STACK_H
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#include <utils/Debug.h>
+
+namespace android {
+// ---------------------------------------------------------------------------
+
+#define NUM_DISPLAY_MAX 4
+
+struct display_cblk_t
+{
+    uint16_t    w;
+    uint16_t    h;
+    uint8_t     format;
+    uint8_t     orientation;
+    uint8_t     reserved[2];
+    float       fps;
+    float       density;
+    float       xdpi;
+    float       ydpi;
+    uint32_t    pad[2];
+};
+
+struct surface_flinger_cblk_t   // 4KB max
+{
+    uint8_t         connected;
+    uint8_t         reserved[3];
+    uint32_t        pad[7];
+    display_cblk_t  displays[NUM_DISPLAY_MAX];
+};
+
+// ---------------------------------------------------------------------------
+
+COMPILE_TIME_ASSERT(sizeof(surface_flinger_cblk_t) <= 4096)
+
+// ---------------------------------------------------------------------------
+}; // namespace android
+
+#endif /* ANDROID_SF_SHARED_BUFFER_STACK_H */