fs3270: remove extra locks

get_current_tty now does internal locking and returns a referenced object,
thus our use of tty_mutex here can go away.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 5 deletions

diff --git a/drivers/s390/char/fs3270.c b/drivers/s390/char/fs3270.c
index 84fbc90480d..1227f4591f8 100644
--- a/drivers/s390/char/fs3270.c
+++ b/drivers/s390/char/fs3270.c
@@ -426,18 +426,14 @@ fs3270_open(struct inode *inode, struct file *filp)
         minor = iminor(filp->f_path.dentry->d_inode);
         /* Check for minor 0 multiplexer. */
         if (minor == 0) {
-                struct tty_struct *tty;
-                mutex_lock(&tty_mutex);
-                tty = get_current_tty();
+                struct tty_struct *tty = get_current_tty();
                 if (!tty || tty->driver->major != IBM_TTY3270_MAJOR) {
                         tty_kref_put(tty);
-                        mutex_unlock(&tty_mutex);
                         rc = -ENODEV;
                         goto out;
                 }
                 minor = tty->index + RAW3270_FIRSTMINOR;
                 tty_kref_put(tty);
-                mutex_unlock(&tty_mutex);
         }
         /* Check if some other program is already using fullscreen mode. */
         fp = (struct fs3270 *) raw3270_find_view(&fs3270_fn, minor);