[PATCH] tty: tty_jobctrl: use guard() in tiocgsid()

[John de la Garza <john@jjdev.com>]

guard()s express more clearly what the lock protects and let the
function return immediately instead of jumping to an unlock label.

Signed-off-by: John de la Garza <john@jjdev.com>
---
 drivers/tty/tty_jobctrl.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/tty/tty_jobctrl.c b/drivers/tty/tty_jobctrl.c
index ef8741c3e662..939569f12119 100644
--- a/drivers/tty/tty_jobctrl.c
+++ b/drivers/tty/tty_jobctrl.c
@@ -542,7 +542,6 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
  */
 static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p)
 {
-	unsigned long flags;
 	pid_t sid;
 
 	/*
@@ -552,17 +551,13 @@ static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t _
 	if (tty == real_tty && current->signal->tty != real_tty)
 		return -ENOTTY;
 
-	spin_lock_irqsave(&real_tty->ctrl.lock, flags);
-	if (!real_tty->ctrl.session)
-		goto err;
-	sid = pid_vnr(real_tty->ctrl.session);
-	spin_unlock_irqrestore(&real_tty->ctrl.lock, flags);
+	scoped_guard(spinlock_irqsave, &real_tty->ctrl.lock) {
+		if (!real_tty->ctrl.session)
+			return -ENOTTY;
+		sid = pid_vnr(real_tty->ctrl.session);
+	}
 
 	return put_user(sid, p);
-
-err:
-	spin_unlock_irqrestore(&real_tty->ctrl.lock, flags);
-	return -ENOTTY;
 }
 
 /*
-- 
2.54.0