diff options
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/n_tty.c | 12 |
1 files changed, 4 insertions, 8 deletions
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index f63b25bbe895..7aeabb719526 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -1669,9 +1669,8 @@ n_tty_receive_buf_common(struct tty_struct *tty, const unsigned char *cp, while (1) { /* - * When PARMRK is set, multiply read_cnt by 3, since each byte - * might take up to three times as many spaces (depending on - * its flags, e.g. parity error). [This calculation is wrong.] + * When PARMRK is set, each input char may take up to 3 chars + * in the read buf; reduce the buffer space avail by 3x * * If we are doing input canonicalization, and there are no * pending newlines, let characters through without limit, so @@ -1683,13 +1682,10 @@ n_tty_receive_buf_common(struct tty_struct *tty, const unsigned char *cp, * read_tail (so this producer will not overwrite unread data) */ size_t tail = smp_load_acquire(&ldata->read_tail); - size_t head = ldata->read_head; + room = N_TTY_BUF_SIZE - (ldata->read_head - tail) - 1; if (I_PARMRK(tty)) - room = N_TTY_BUF_SIZE - (head - tail) * 3 - 1; - else - room = N_TTY_BUF_SIZE - (head - tail) - 1; - + room /= 3; if (room <= 0) room = ldata->icanon && ldata->canon_head == tail; |