[SAFS]: fix a bug in aio.
[SAFS]: fix a bug in aio.

zheng-da/FlashX,icoming/FlashX,icoming/FlashGraph,icoming/FlashX,zheng-da/FlashX,zheng-da/FlashX,icoming/FlashX,icoming/FlashX,flashxio/FlashX,flashxio/FlashX,icoming/FlashGraph,icoming/FlashGraph,flashxio/FlashX,zheng-da/FlashX,flashxio/FlashX,icoming/FlashGraph,flashxio/FlashX,flashxio/FlashX,icoming/FlashGraph,icoming/FlashX,zheng-da/FlashX