RWF_ATOMIC
if (flags & RWF_ATOMIC) {
#define IOCB_ATOMIC (__force int) RWF_ATOMIC
RWF_APPEND | RWF_NOAPPEND | RWF_ATOMIC |\
RWF_APPEND | RWF_NOAPPEND | RWF_ATOMIC |\
RWF_APPEND | RWF_NOAPPEND | RWF_ATOMIC |\