diff --git a/dlls/wineoss.drv/oss.c b/dlls/wineoss.drv/oss.c
index 40b8879ef47..9f2cba68f86 100644
--- a/dlls/wineoss.drv/oss.c
+++ b/dlls/wineoss.drv/oss.c
@@ -1641,3 +1641,356 @@ unixlib_entry_t __wine_unix_call_funcs[] =
     midi_notify_wait,
     aux_message,
 };
+
+#ifdef _WIN64
+
+typedef UINT PTR32;
+
+static NTSTATUS wow64_get_endpoint_ids(void *args)
+{
+    struct
+    {
+        EDataFlow flow;
+        PTR32 endpoints;
+        unsigned int size;
+        HRESULT result;
+        unsigned int num;
+        unsigned int default_idx;
+    } *params32 = args;
+    struct get_endpoint_ids_params params =
+    {
+        .flow = params32->flow,
+        .endpoints = ULongToPtr(params32->endpoints),
+        .size = params32->size
+    };
+    get_endpoint_ids(&params);
+    params32->size = params.size;
+    params32->result = params.result;
+    params32->num = params.num;
+    params32->default_idx = params.default_idx;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_create_stream(void *args)
+{
+    struct
+    {
+        PTR32 device;
+        EDataFlow flow;
+        AUDCLNT_SHAREMODE share;
+        UINT flags;
+        REFERENCE_TIME duration;
+        REFERENCE_TIME period;
+        PTR32 fmt;
+        HRESULT result;
+        PTR32 stream;
+    } *params32 = args;
+    struct create_stream_params params =
+    {
+        .device = ULongToPtr(params32->device),
+        .flow = params32->flow,
+        .share = params32->share,
+        .flags = params32->flags,
+        .duration = params32->duration,
+        .period = params32->period,
+        .fmt = ULongToPtr(params32->fmt),
+        .stream = ULongToPtr(params32->stream)
+    };
+    create_stream(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_release_stream(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        PTR32 timer_thread;
+        HRESULT result;
+    } *params32 = args;
+    struct release_stream_params params =
+    {
+        .stream = params32->stream,
+        .timer_thread = ULongToHandle(params32->timer_thread)
+    };
+    release_stream(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_get_render_buffer(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        UINT32 frames;
+        HRESULT result;
+        PTR32 data;
+    } *params32 = args;
+    BYTE *data = NULL;
+    struct get_render_buffer_params params =
+    {
+        .stream = params32->stream,
+        .frames = params32->frames,
+        .data = &data
+    };
+    get_render_buffer(&params);
+    params32->result = params.result;
+    *(unsigned int *)ULongToPtr(params32->data) = PtrToUlong(data);
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_get_capture_buffer(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        HRESULT result;
+        PTR32 data;
+        PTR32 frames;
+        PTR32 flags;
+        PTR32 devpos;
+        PTR32 qpcpos;
+    } *params32 = args;
+    BYTE *data = NULL;
+    struct get_capture_buffer_params params =
+    {
+        .stream = params32->stream,
+        .data = &data,
+        .frames = ULongToPtr(params32->frames),
+        .flags = ULongToPtr(params32->flags),
+        .devpos = ULongToPtr(params32->devpos),
+        .qpcpos = ULongToPtr(params32->qpcpos)
+    };
+    get_capture_buffer(&params);
+    params32->result = params.result;
+    *(unsigned int *)ULongToPtr(params32->data) = PtrToUlong(data);
+    return STATUS_SUCCESS;
+};
+
+static NTSTATUS wow64_is_format_supported(void *args)
+{
+    struct
+    {
+        PTR32 device;
+        EDataFlow flow;
+        AUDCLNT_SHAREMODE share;
+        PTR32 fmt_in;
+        PTR32 fmt_out;
+        HRESULT result;
+    } *params32 = args;
+    struct is_format_supported_params params =
+    {
+        .device = ULongToPtr(params32->device),
+        .flow = params32->flow,
+        .share = params32->share,
+        .fmt_in = ULongToPtr(params32->fmt_in),
+        .fmt_out = ULongToPtr(params32->fmt_out)
+    };
+    is_format_supported(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_get_mix_format(void *args)
+{
+    struct
+    {
+        PTR32 device;
+        EDataFlow flow;
+        PTR32 fmt;
+        HRESULT result;
+    } *params32 = args;
+    struct get_mix_format_params params =
+    {
+        .device = ULongToPtr(params32->device),
+        .flow = params32->flow,
+        .fmt = ULongToPtr(params32->fmt)
+    };
+    get_mix_format(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_get_buffer_size(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        HRESULT result;
+        PTR32 size;
+    } *params32 = args;
+    struct get_buffer_size_params params =
+    {
+        .stream = params32->stream,
+        .size = ULongToPtr(params32->size)
+    };
+    get_buffer_size(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_get_latency(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        HRESULT result;
+        PTR32 latency;
+    } *params32 = args;
+    struct get_latency_params params =
+    {
+        .stream = params32->stream,
+        .latency = ULongToPtr(params32->latency)
+    };
+    get_latency(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_get_current_padding(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        HRESULT result;
+        PTR32 padding;
+    } *params32 = args;
+    struct get_current_padding_params params =
+    {
+        .stream = params32->stream,
+        .padding = ULongToPtr(params32->padding)
+    };
+    get_current_padding(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_get_next_packet_size(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        HRESULT result;
+        PTR32 frames;
+    } *params32 = args;
+    struct get_next_packet_size_params params =
+    {
+        .stream = params32->stream,
+        .frames = ULongToPtr(params32->frames)
+    };
+    get_next_packet_size(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_get_frequency(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        HRESULT result;
+        PTR32 frequency;
+    } *params32 = args;
+    struct get_frequency_params params =
+    {
+        .stream = params32->stream,
+        .frequency = ULongToPtr(params32->frequency)
+    };
+    get_frequency(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_get_position(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        HRESULT result;
+        PTR32 position;
+        PTR32 qpctime;
+    } *params32 = args;
+    struct get_position_params params =
+    {
+        .stream = params32->stream,
+        .position = ULongToPtr(params32->position),
+        .qpctime = ULongToPtr(params32->qpctime)
+    };
+    get_position(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS wow64_set_volumes(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        float master_volume;
+        PTR32 volumes;
+        PTR32 session_volumes;
+    } *params32 = args;
+    struct set_volumes_params params =
+    {
+        .stream = params32->stream,
+        .master_volume = params32->master_volume,
+        .volumes = ULongToPtr(params32->volumes),
+        .session_volumes = ULongToPtr(params32->session_volumes)
+    };
+    return set_volumes(&params);
+}
+
+static NTSTATUS wow64_set_event_handle(void *args)
+{
+    struct
+    {
+        stream_handle stream;
+        PTR32 event;
+        HRESULT result;
+    } *params32 = args;
+    struct set_event_handle_params params =
+    {
+        .stream = params32->stream,
+        .event = ULongToHandle(params32->event)
+    };
+
+    set_event_handle(&params);
+    params32->result = params.result;
+    return STATUS_SUCCESS;
+}
+
+unixlib_entry_t __wine_unix_call_wow64_funcs[] =
+{
+    test_connect,
+    wow64_get_endpoint_ids,
+    wow64_create_stream,
+    wow64_release_stream,
+    start,
+    stop,
+    reset,
+    timer_loop,
+    wow64_get_render_buffer,
+    release_render_buffer,
+    wow64_get_capture_buffer,
+    release_capture_buffer,
+    wow64_is_format_supported,
+    wow64_get_mix_format,
+    wow64_get_buffer_size,
+    wow64_get_latency,
+    wow64_get_current_padding,
+    wow64_get_next_packet_size,
+    wow64_get_frequency,
+    wow64_get_position,
+    wow64_set_volumes,
+    wow64_set_event_handle,
+    is_started,
+    midi_release,
+    midi_out_message,
+    midi_in_message,
+    midi_notify_wait,
+    aux_message,
+};
+
+#endif /* _WIN64 */