From a51ea39b76ddbe91aa5ccf9f24762ef7c8b0d0cd Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 8 May 2024 06:17:39 +0200 Subject: Merging upstream version 4.19.289. Signed-off-by: Daniel Baumann --- drivers/tty/tty_ioctl.c | 45 +++++++++++++++++++++++++++++++++------------ 1 file changed, 33 insertions(+), 12 deletions(-) (limited to 'drivers/tty/tty_ioctl.c') diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c index d99fec440..095c8780e 100644 --- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -397,21 +397,42 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt) tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios); tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios); - ld = tty_ldisc_ref(tty); + if (opt & (TERMIOS_FLUSH|TERMIOS_WAIT)) { +retry_write_wait: + retval = wait_event_interruptible(tty->write_wait, !tty_chars_in_buffer(tty)); + if (retval < 0) + return retval; - if (ld != NULL) { - if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) - ld->ops->flush_buffer(tty); - tty_ldisc_deref(ld); - } + if (tty_write_lock(tty, 0) < 0) + goto retry_write_wait; - if (opt & TERMIOS_WAIT) { - tty_wait_until_sent(tty, 0); - if (signal_pending(current)) - return -ERESTARTSYS; - } + /* Racing writer? */ + if (tty_chars_in_buffer(tty)) { + tty_write_unlock(tty); + goto retry_write_wait; + } + + ld = tty_ldisc_ref(tty); + if (ld != NULL) { + if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) + ld->ops->flush_buffer(tty); + tty_ldisc_deref(ld); + } + + if ((opt & TERMIOS_WAIT) && tty->ops->wait_until_sent) { + tty->ops->wait_until_sent(tty, 0); + if (signal_pending(current)) { + tty_write_unlock(tty); + return -ERESTARTSYS; + } + } + + tty_set_termios(tty, &tmp_termios); - tty_set_termios(tty, &tmp_termios); + tty_write_unlock(tty); + } else { + tty_set_termios(tty, &tmp_termios); + } /* FIXME: Arguably if tmp_termios == tty->termios AND the actual requested termios was not tmp_termios then we may -- cgit v1.2.3