- /*
- * If the rxbuf is empty and we are not throttled, put as much
- * as we can directly into the linux TTY buffer.
- *
- */
- flip_len = TTY_FLIPBUF_SIZE;
-
- len = min(data_len, flip_len);
- len = min(len, (N_TTY_BUF_SIZE - 1) - tp->read_cnt);
- ld = tty_ldisc_ref(tp);
-
- /*
- * If we were unable to get a reference to the ld,
- * don't flush our buffer, and act like the ld doesn't
- * have any space to put the data right now.
- */
- if (!ld) {
- len = 0;
- } else {
- /*
- * If ld doesn't have a pointer to a receive_buf function,
- * flush the data, then act like the ld doesn't have any
- * space to put the data right now.
- */
- if (!ld->receive_buf) {
- ch->ch_r_head = ch->ch_r_tail;
- len = 0;
- }
- }
-
- if (len <= 0) {