From fdfb719e93b55a50f90da2059dc450e7c0c48e8f Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Sun, 10 Jan 2016 22:40:54 -0800 Subject: tty: Remove chars_in_buffer() line discipline method The chars_in_buffer() line discipline method serves no functional purpose, other than as a (dubious) debugging aid for mostly bit-rotting drivers. Despite being documented as an optional method, every caller is unconditionally executed (although conditionally compiled). Furthermore, direct tty->ldisc access without an ldisc ref is unsafe. Lastly, N_TTY's chars_in_buffer() has warned of removal since 3.12. Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_tty.c | 23 ----------------------- 1 file changed, 23 deletions(-) (limited to 'drivers/tty/n_tty.c') diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index b280abaad91b..90eca2605fbf 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -380,28 +380,6 @@ static void n_tty_flush_buffer(struct tty_struct *tty) up_write(&tty->termios_rwsem); } -/** - * n_tty_chars_in_buffer - report available bytes - * @tty: tty device - * - * Report the number of characters buffered to be delivered to user - * at this instant in time. - * - * Locking: exclusive termios_rwsem - */ - -static ssize_t n_tty_chars_in_buffer(struct tty_struct *tty) -{ - ssize_t n; - - WARN_ONCE(1, "%s is deprecated and scheduled for removal.", __func__); - - down_write(&tty->termios_rwsem); - n = chars_in_buffer(tty); - up_write(&tty->termios_rwsem); - return n; -} - /** * is_utf8_continuation - utf8 multibyte check * @c: byte to check @@ -2525,7 +2503,6 @@ struct tty_ldisc_ops tty_ldisc_N_TTY = { .open = n_tty_open, .close = n_tty_close, .flush_buffer = n_tty_flush_buffer, - .chars_in_buffer = n_tty_chars_in_buffer, .read = n_tty_read, .write = n_tty_write, .ioctl = n_tty_ioctl, -- cgit v1.2.3