RWF_APPEND
if (unlikely((flags & RWF_APPEND) && (flags & RWF_NOAPPEND)))
#define IOCB_APPEND (__force int) RWF_APPEND
RWF_APPEND | RWF_NOAPPEND | RWF_ATOMIC |\
RWF_APPEND | RWF_NOAPPEND | RWF_ATOMIC |\
RWF_APPEND | RWF_NOAPPEND | RWF_ATOMIC |\