func: void bdrv_invalidate_cache_all(Error **errp)
  
  {
  
      BlockDriverState *bs;
  
      Error *local_err = NULL;
  
      BdrvNextIterator *it = NULL;
  
  
  
      while ((it = bdrv_next(it, &bs)) != NULL) {
  
          AioContext *aio_context = bdrv_get_aio_context(bs);
  
  
  
          aio_context_acquire(aio_context);
  
          bdrv_invalidate_cache(bs, &local_err);
  
          aio_context_release(aio_context);
  
          if (local_err) {
  
              error_propagate(errp, local_err);
  
              return;
  
          }
  
      }
  
  }
  