diff --git a/include/exstubs.h b/include/exstubs.h
index 17168ae9..75a5f891 100644
--- a/include/exstubs.h
+++ b/include/exstubs.h
@@ -96,17 +96,27 @@ typedef struct _DriDriver DriDriver;
  * MiniGUI NEWGAL engine for hardware surface.
  */
 typedef struct _DriSurfaceBuffer {
+    /** The handle of the buffer */
     uint32_t handle;
+    /** The buffer identifier */
     uint32_t id;
+    /** The widht of the buffer */
     uint32_t width;
+    /** The height of the buffer */
     uint32_t height;
+    /** The pitch (row stride in bytes) of the buffer */
     uint32_t pitch;
+    /** The DRM format of the buffer */
     uint32_t drm_format;
 
+    /** The bits per pixel */
     uint16_t bpp:8;
+    /** The bytes per pixel */
     uint16_t cpp:8;
 
+    /** The whole size in bytes of the buffer */
     unsigned long size;
+    /** The mapped address of the buffer; NULL when the buffer is not mapped yet. */
     uint8_t* pixels;
 } DriSurfaceBuffer;
 
@@ -159,35 +169,26 @@ typedef struct _DriDriverOps {
 
     /**
      * This operation creates a buffer with the specified pixel format,
-     * width, and height. If succeed, a valid (not zero) buffer identifier,
-     * the picth (row stride in bytes), and the handle will be returned.
-     * If failed, it returns 0.
+     * width, and height. If succeed, a valid DriSurfaceBuffer object will
+     * be returned; NULL on error. Note that the field of `pixels` of the
+     * DriSurfaceBuffer object is NULL until the \a map_buffer was called.
      *
      * \note The driver must implement this operation.
      */
-    uint32_t (* create_buffer) (DriDriver *driver,
+    DriSurfaceBuffer* (* create_buffer) (DriDriver *driver,
             uint32_t drm_format,
-            unsigned int width, unsigned int height,
-            unsigned int *pitch);
+            unsigned int width, unsigned int height);
 
     /**
      * This operation creates a buffer for the given system global name
      * with the specified pixel format, width, and height. If succeed,
-     * a valid (not zero) buffer identifier,
-     * the picth (row stride in bytes), and the handle will be returned.
-     * If failed, it returns 0.
+     * a valid DriSurfaceBuffer object will be returned; NULL on error.
      *
      * \note The driver must implement this operation.
      */
-    uint32_t (* create_buffer_from_name) (DriDriver *driver,
+    DriSurfaceBuffer* (* create_buffer_from_name) (DriDriver *driver,
             uint32_t name, uint32_t drm_format,
-            unsigned int width, unsigned int height,
-            unsigned int *pitch);
-
-    BOOL (* fetch_buffer) (DriDriver *driver,
-            uint32_t buffer_id,
-            unsigned int *width, unsigned int *height,
-            unsigned int *pitch);
+            unsigned int width, unsigned int height);
 
     /**
      * This operation maps the buffer into the current process's virtual memory
@@ -195,8 +196,7 @@ typedef struct _DriDriverOps {
      *
      * \note The driver must implement this operation.
      */
-    DriSurfaceBuffer* (* map_buffer) (DriDriver *driver,
-            uint32_t buffer_id);
+    uint8_t* (* map_buffer) (DriDriver *driver, DriSurfaceBuffer* buffer);
 
     /**
      * This operation un-maps a buffer.
@@ -210,7 +210,7 @@ typedef struct _DriDriverOps {
      *
      * \note The driver must implement this operation.
      */
-    void (* destroy_buffer) (DriDriver *driver, uint32_t buffer_id);
+    void (* destroy_buffer) (DriDriver *driver, DriSurfaceBuffer* buffer);
 
     /**
      * This operation clears the specific rectangle area of a buffer
diff --git a/src/newgal/dri/drivideo.c b/src/newgal/dri/drivideo.c
index 294376b8..ec37160a 100644
--- a/src/newgal/dri/drivideo.c
+++ b/src/newgal/dri/drivideo.c
@@ -157,8 +157,6 @@ static void drm_cleanup(DriVideoData* vdata)
     if (vdata->scanout_fb) {
         if (vdata->driver_ops) {
             // do nothing for hardware surface.
-            // vdata->driver_ops->unmap_buffer(vdata->driver, vdata->scanout_buff_id);
-            // vdata->driver_ops->destroy_buffer(vdata->driver, vdata->scanout_buff_id);
         }
         else {
             /* dumb buffer */
@@ -1378,7 +1376,6 @@ static GAL_Surface *DRI_SetVideoMode_Accl(_THIS, GAL_Surface *current,
     uint32_t drm_format;
     Uint32 RGBAmasks[4];
     DriSurfaceBuffer* scanout_buff = NULL;
-    unsigned int pitch;
 
     drm_format = get_drm_format_from_etc(&bpp);
     if (drm_format == 0) {
@@ -1404,15 +1401,14 @@ static GAL_Surface *DRI_SetVideoMode_Accl(_THIS, GAL_Surface *current,
 #endif
 
     /* create the scanout buffer and set up it as frame buffer */
-    vdata->scanout_buff_id =
-        vdata->driver_ops->create_buffer(vdata->driver, drm_format,
-            info->width, info->height, &pitch);
-    if (vdata->scanout_buff_id == 0) {
+    scanout_buff = vdata->driver_ops->create_buffer(vdata->driver, drm_format,
+            info->width, info->height);
+    if (scanout_buff == NULL) {
+        _ERR_PRINTF ("NEWGAL>DRM: cannot create scanout frame buffer: %m\n");
         goto error;
     }
 
-    scanout_buff = vdata->driver_ops->map_buffer(vdata->driver, vdata->scanout_buff_id);
-    if (scanout_buff == NULL) {
+    if (NULL == vdata->driver_ops->map_buffer(vdata->driver, scanout_buff)) {
         _ERR_PRINTF ("NEWGAL>DRM: cannot map scanout frame buffer: %m\n");
         goto error;
     }
@@ -1420,9 +1416,10 @@ static GAL_Surface *DRI_SetVideoMode_Accl(_THIS, GAL_Surface *current,
     vdata->width = info->width;
     vdata->height = info->height;
     vdata->bpp = bpp;
-    vdata->pitch = pitch;
-    vdata->size = pitch * info->height;
+    vdata->pitch = scanout_buff->pitch;
+    vdata->size = scanout_buff->pitch * info->height;
     vdata->handle = 0;
+    vdata->scanout_buff_id = scanout_buff->id;
     vdata->scanout_fb = scanout_buff->pixels;
 
     _DBG_PRINTF("NEWGAL>DRM: scanout frame buffer: size (%dx%d), pitch(%d)\n",
@@ -1483,7 +1480,7 @@ error:
     }
 
     if (vdata->scanout_buff_id) {
-        vdata->driver_ops->destroy_buffer(vdata->driver, vdata->scanout_buff_id);
+        vdata->driver_ops->destroy_buffer(vdata->driver, scanout_buff);
         vdata->scanout_buff_id = 0;
     }
 
@@ -1494,8 +1491,6 @@ static int DRI_AllocHWSurface_Accl(_THIS, GAL_Surface *surface)
 {
     DriVideoData* vdata = this->hidden;
     uint32_t drm_format;
-    unsigned int pitch;
-    uint32_t buff_id = 0;
     DriSurfaceBuffer* surface_buffer;
 
     drm_format = translate_gal_format(surface->format);
@@ -1506,27 +1501,26 @@ static int DRI_AllocHWSurface_Accl(_THIS, GAL_Surface *surface)
         return -1;
     }
 
-    buff_id = vdata->driver_ops->create_buffer(vdata->driver, drm_format,
-            surface->w, surface->h, &pitch);
-    if (buff_id == 0) {
+    surface_buffer = vdata->driver_ops->create_buffer(vdata->driver, drm_format,
+            surface->w, surface->h);
+    if (surface_buffer == NULL) {
         return -1;
     }
 
-    surface_buffer = vdata->driver_ops->map_buffer(vdata->driver, buff_id);
-    if (surface_buffer == NULL) {
+    if (vdata->driver_ops->map_buffer(vdata->driver, surface_buffer) == NULL) {
         _ERR_PRINTF ("NEWGAL>DRM: cannot map hardware buffer: %m\n");
         goto error;
     }
 
     surface->pixels = surface_buffer->pixels;
     surface->flags |= GAL_HWSURFACE;
-    surface->pitch = pitch;
+    surface->pitch = surface_buffer->pitch;
     surface->hwdata = (struct private_hwdata *)surface_buffer;
     return 0;
 
 error:
-    if (buff_id)
-        vdata->driver_ops->destroy_buffer(vdata->driver, buff_id);
+    if (surface_buffer)
+        vdata->driver_ops->destroy_buffer(vdata->driver, surface_buffer);
 
     return -1;
 }
@@ -1538,8 +1532,9 @@ static void DRI_FreeHWSurface_Accl(_THIS, GAL_Surface *surface)
 
     surface_buffer = (DriSurfaceBuffer*)surface->hwdata;
     if (surface_buffer) {
-        vdata->driver_ops->unmap_buffer(vdata->driver, surface_buffer);
-        vdata->driver_ops->destroy_buffer(vdata->driver, surface_buffer->id);
+        if (surface_buffer->pixels)
+            vdata->driver_ops->unmap_buffer(vdata->driver, surface_buffer);
+        vdata->driver_ops->destroy_buffer(vdata->driver, surface_buffer);
     }
 
     surface->pixels = NULL;