void qemu_chr_be_write_impl(CharDriverState *s, uint8_t *buf, int len)
{
    CharBackend *be = s->be;

    if (be && be->chr_read) {
        be->chr_read(be->opaque, buf, len);
    }
}
void qemu_chr_be_write_impl(CharDriverState *s, uint8_t *buf, int len)
{
    CharBackend *be = s->be;

    if (be && be->chr_read) {
        be->chr_read(be->opaque, buf, len);
    }
}