TTY: remove tty_locked

We used it really only serial and ami_serial. The rest of the
callsites were BUG/WARN_ONs to check if BTM is held. Now that we
pruned tty_locked from both of the real users, we can get rid of
tty_lock along with __big_tty_mutex_owner.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 0 insertions, 12 deletions

diff --git a/drivers/tty/tty_mutex.c b/drivers/tty/tty_mutex.c
index 3b2bb7719442..9ff986c32a21 100644
--- a/drivers/tty/tty_mutex.c
+++ b/drivers/tty/tty_mutex.c
@@ -15,30 +15,18 @@
  * Don't use in new code.
  */
 static DEFINE_MUTEX(big_tty_mutex);
-struct task_struct *__big_tty_mutex_owner;
-EXPORT_SYMBOL_GPL(__big_tty_mutex_owner);
 
 /*
  * Getting the big tty mutex.
  */
 void __lockfunc tty_lock(void)
 {
-        struct task_struct *task = current;
-
-        WARN_ON(__big_tty_mutex_owner == task);
-
         mutex_lock(&big_tty_mutex);
-        __big_tty_mutex_owner = task;
 }
 EXPORT_SYMBOL(tty_lock);
 
 void __lockfunc tty_unlock(void)
 {
-        struct task_struct *task = current;
-
-        WARN_ON(__big_tty_mutex_owner != task);
-        __big_tty_mutex_owner = NULL;
-
         mutex_unlock(&big_tty_mutex);
 }
 EXPORT_SYMBOL(tty_unlock);