diff --git a/dlls/d3d9/d3d9_private.h b/dlls/d3d9/d3d9_private.h
index 0947a54d2d48753f2b9d94b82f74a60e2fb2a877..4d13ce730e5481f7cd606c996aa92c89d3695330 100644
--- a/dlls/d3d9/d3d9_private.h
+++ b/dlls/d3d9/d3d9_private.h
@@ -377,15 +377,14 @@ HRESULT volumetexture_init(IDirect3DVolumeTexture9Impl *texture, IDirect3DDevice
  * IDirect3DStateBlock9 implementation structure
  */
 typedef struct  IDirect3DStateBlock9Impl {
-    /* IUnknown fields */
-    const IDirect3DStateBlock9Vtbl *lpVtbl;
+    IDirect3DStateBlock9    IDirect3DStateBlock9_iface;
     LONG                    ref;
 
     /* IDirect3DStateBlock9 fields */
     struct wined3d_stateblock *wined3d_stateblock;
 
     /* Parent reference */
-    LPDIRECT3DDEVICE9EX       parentDevice;
+    IDirect3DDevice9Ex      *parentDevice;
 } IDirect3DStateBlock9Impl;
 
 HRESULT stateblock_init(IDirect3DStateBlock9Impl *stateblock, IDirect3DDevice9Impl *device,
diff --git a/dlls/d3d9/device.c b/dlls/d3d9/device.c
index bd5b1676daccdd2f62276f07d5aeef9526d23241..1f38f36337297ba3d3eaa26b5994cd3e551d14c8 100644
--- a/dlls/d3d9/device.c
+++ b/dlls/d3d9/device.c
@@ -1509,7 +1509,7 @@ static HRESULT WINAPI IDirect3DDevice9Impl_CreateStateBlock(IDirect3DDevice9Ex *
     }
 
     TRACE("Created stateblock %p.\n", object);
-    *stateblock = (IDirect3DStateBlock9 *)object;
+    *stateblock = &object->IDirect3DStateBlock9_iface;
 
     return D3D_OK;
 }
@@ -1568,7 +1568,7 @@ static HRESULT WINAPI IDirect3DDevice9Impl_EndStateBlock(IDirect3DDevice9Ex *ifa
     }
 
     TRACE("Created stateblock %p.\n", object);
-    *stateblock = (IDirect3DStateBlock9 *)object;
+    *stateblock = &object->IDirect3DStateBlock9_iface;
 
     return D3D_OK;
 }
diff --git a/dlls/d3d9/stateblock.c b/dlls/d3d9/stateblock.c
index 13f2b9f02df6c8652c0269c0faf928cd25503b50..46a4de55393753013b1c1ba50aeb03d15b3e2d43 100644
--- a/dlls/d3d9/stateblock.c
+++ b/dlls/d3d9/stateblock.c
@@ -25,9 +25,15 @@
 
 WINE_DEFAULT_DEBUG_CHANNEL(d3d9);
 
-/* IDirect3DStateBlock9 IUnknown parts follow: */
-static HRESULT WINAPI IDirect3DStateBlock9Impl_QueryInterface(LPDIRECT3DSTATEBLOCK9 iface, REFIID riid, LPVOID* ppobj) {
-    IDirect3DStateBlock9Impl *This = (IDirect3DStateBlock9Impl *)iface;
+static inline IDirect3DStateBlock9Impl *impl_from_IDirect3DStateBlock9(IDirect3DStateBlock9 *iface)
+{
+    return CONTAINING_RECORD(iface, IDirect3DStateBlock9Impl, IDirect3DStateBlock9_iface);
+}
+
+static HRESULT WINAPI IDirect3DStateBlock9Impl_QueryInterface(IDirect3DStateBlock9 *iface,
+        REFIID riid, void **ppobj)
+{
+    IDirect3DStateBlock9Impl *This = impl_from_IDirect3DStateBlock9(iface);
 
     TRACE("iface %p, riid %s, object %p.\n", iface, debugstr_guid(riid), ppobj);
 
@@ -43,8 +49,9 @@ static HRESULT WINAPI IDirect3DStateBlock9Impl_QueryInterface(LPDIRECT3DSTATEBLO
     return E_NOINTERFACE;
 }
 
-static ULONG WINAPI IDirect3DStateBlock9Impl_AddRef(LPDIRECT3DSTATEBLOCK9 iface) {
-    IDirect3DStateBlock9Impl *This = (IDirect3DStateBlock9Impl *)iface;
+static ULONG WINAPI IDirect3DStateBlock9Impl_AddRef(IDirect3DStateBlock9 *iface)
+{
+    IDirect3DStateBlock9Impl *This = impl_from_IDirect3DStateBlock9(iface);
     ULONG ref = InterlockedIncrement(&This->ref);
 
     TRACE("%p increasing refcount to %u.\n", iface, ref);
@@ -52,8 +59,9 @@ static ULONG WINAPI IDirect3DStateBlock9Impl_AddRef(LPDIRECT3DSTATEBLOCK9 iface)
     return ref;
 }
 
-static ULONG WINAPI IDirect3DStateBlock9Impl_Release(LPDIRECT3DSTATEBLOCK9 iface) {
-    IDirect3DStateBlock9Impl *This = (IDirect3DStateBlock9Impl *)iface;
+static ULONG WINAPI IDirect3DStateBlock9Impl_Release(IDirect3DStateBlock9 *iface)
+{
+    IDirect3DStateBlock9Impl *This = impl_from_IDirect3DStateBlock9(iface);
     ULONG ref = InterlockedDecrement(&This->ref);
 
     TRACE("%p decreasing refcount to %u.\n", iface, ref);
@@ -70,9 +78,10 @@ static ULONG WINAPI IDirect3DStateBlock9Impl_Release(LPDIRECT3DSTATEBLOCK9 iface
 }
 
 /* IDirect3DStateBlock9 Interface follow: */
-static HRESULT WINAPI IDirect3DStateBlock9Impl_GetDevice(IDirect3DStateBlock9 *iface, IDirect3DDevice9 **device)
+static HRESULT WINAPI IDirect3DStateBlock9Impl_GetDevice(IDirect3DStateBlock9 *iface,
+        IDirect3DDevice9 **device)
 {
-    IDirect3DStateBlock9Impl *This = (IDirect3DStateBlock9Impl *)iface;
+    IDirect3DStateBlock9Impl *This = impl_from_IDirect3DStateBlock9(iface);
 
     TRACE("iface %p, device %p.\n", iface, device);
 
@@ -84,8 +93,9 @@ static HRESULT WINAPI IDirect3DStateBlock9Impl_GetDevice(IDirect3DStateBlock9 *i
     return D3D_OK;
 }
 
-static HRESULT WINAPI IDirect3DStateBlock9Impl_Capture(LPDIRECT3DSTATEBLOCK9 iface) {
-    IDirect3DStateBlock9Impl *This = (IDirect3DStateBlock9Impl *)iface;
+static HRESULT WINAPI IDirect3DStateBlock9Impl_Capture(IDirect3DStateBlock9 *iface)
+{
+    IDirect3DStateBlock9Impl *This = impl_from_IDirect3DStateBlock9(iface);
     HRESULT hr;
 
     TRACE("iface %p.\n", iface);
@@ -97,8 +107,9 @@ static HRESULT WINAPI IDirect3DStateBlock9Impl_Capture(LPDIRECT3DSTATEBLOCK9 ifa
     return hr;
 }
 
-static HRESULT WINAPI IDirect3DStateBlock9Impl_Apply(LPDIRECT3DSTATEBLOCK9 iface) {
-    IDirect3DStateBlock9Impl *This = (IDirect3DStateBlock9Impl *)iface;
+static HRESULT WINAPI IDirect3DStateBlock9Impl_Apply(IDirect3DStateBlock9 *iface)
+{
+    IDirect3DStateBlock9Impl *This = impl_from_IDirect3DStateBlock9(iface);
     HRESULT hr;
 
     TRACE("iface %p.\n", iface);
@@ -128,7 +139,7 @@ HRESULT stateblock_init(IDirect3DStateBlock9Impl *stateblock, IDirect3DDevice9Im
 {
     HRESULT hr;
 
-    stateblock->lpVtbl = &Direct3DStateBlock9_Vtbl;
+    stateblock->IDirect3DStateBlock9_iface.lpVtbl = &Direct3DStateBlock9_Vtbl;
     stateblock->ref = 1;
 
     if (wined3d_stateblock)