tty: remove unneeded mbz from tiocsti()

'mbz' in tiocsti() is used only to pass TTY_NORMAL to
tty_ldisc_ops::receive_buf(). But that can be achieved easier by simply
passing NULL to ::receive_buf().

So drop this 'mbz'.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20231121092258.9334-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index ee5a90f9adb54d870a3d28e1a06dbadf2f510475..005d91c63707224c0d0249a6167a39d6bb04b5f2 100644 (file)
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2280,7 +2280,7 @@ static bool tty_legacy_tiocsti __read_mostly = IS_ENABLED(CONFIG_LEGACY_TIOCSTI)
  */
 static int tiocsti(struct tty_struct *tty, char __user *p)
 {
-       char ch, mbz = 0;
+       char ch;
        struct tty_ldisc *ld;
 
        if (!tty_legacy_tiocsti && !capable(CAP_SYS_ADMIN))
@@ -2296,7 +2296,7 @@ static int tiocsti(struct tty_struct *tty, char __user *p)
                return -EIO;
        tty_buffer_lock_exclusive(tty->port);
        if (ld->ops->receive_buf)
-               ld->ops->receive_buf(tty, &ch, &mbz, 1);
+               ld->ops->receive_buf(tty, &ch, NULL, 1);
        tty_buffer_unlock_exclusive(tty->port);
        tty_ldisc_deref(ld);
        return 0;