linux-kernel - [PATCH 2/4] tty: vt: simplify some cases in tioclinux()

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Message-Id: <20230420093559.13200-2-jirislaby@kernel.org>
Date:   Thu, 20 Apr 2023 11:35:57 +0200
From:   "Jiri Slaby (SUSE)" <jirislaby@...nel.org>
To:     gregkh@...uxfoundation.org
Cc:     linux-kernel@...r.kernel.org,
        "Jiri Slaby (SUSE)" <jirislaby@...nel.org>
Subject: [PATCH 2/4] tty: vt: simplify some cases in tioclinux()

There is no need to set "ret" variable and break. We can simply return
from the cases. This makes the code much easier to follow, as many else
branches are redundant.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@...nel.org>
---
 drivers/tty/vt/vt.c | 62 +++++++++++++++++++--------------------------
 1 file changed, 26 insertions(+), 36 deletions(-)

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 2dffee1e114a..f44d5b8a102c 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -3145,12 +3145,10 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
 
 	switch (type) {
 	case TIOCL_SETSEL:
-		ret = set_selection_user((struct tiocl_selection
+		return set_selection_user((struct tiocl_selection
 					 __user *)(p+1), tty);
-		break;
 	case TIOCL_PASTESEL:
-		ret = paste_selection(tty);
-		break;
+		return paste_selection(tty);
 	case TIOCL_UNBLANKSCREEN:
 		console_lock();
 		unblank_screen();
@@ -3169,14 +3167,12 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
 		 * this.
 		 */
 		data = vt_get_shift_state();
-		ret = put_user(data, p);
-		break;
+		return put_user(data, p);
 	case TIOCL_GETMOUSEREPORTING:
 		console_lock();	/* May be overkill */
 		data = mouse_reporting();
 		console_unlock();
-		ret = put_user(data, p);
-		break;
+		return put_user(data, p);
 	case TIOCL_SETVESABLANK:
 		console_lock();
 		ret = set_vesa_blanking(p);
@@ -3184,38 +3180,34 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
 		break;
 	case TIOCL_GETKMSGREDIRECT:
 		data = vt_get_kmsg_redirect();
-		ret = put_user(data, p);
-		break;
+		return put_user(data, p);
 	case TIOCL_SETKMSGREDIRECT:
-		if (!capable(CAP_SYS_ADMIN)) {
-			ret = -EPERM;
-		} else {
-			if (get_user(data, p+1))
-				ret = -EFAULT;
-			else
-				vt_kmsg_redirect(data);
-		}
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+
+		if (get_user(data, p+1))
+			return -EFAULT;
+
+		vt_kmsg_redirect(data);
+
 		break;
 	case TIOCL_GETFGCONSOLE:
 		/*
 		 * No locking needed as this is a transiently correct return
 		 * anyway if the caller hasn't disabled switching.
 		 */
-		ret = fg_console;
-		break;
+		return fg_console;
 	case TIOCL_SCROLLCONSOLE:
-		if (get_user(lines, (s32 __user *)(p+4))) {
-			ret = -EFAULT;
-		} else {
-			/*
-			 * Needs the console lock here. Note that lots of other
-			 * calls need fixing before the lock is actually useful!
-			 */
-			console_lock();
-			scrollfront(vc_cons[fg_console].d, lines);
-			console_unlock();
-			ret = 0;
-		}
+		if (get_user(lines, (s32 __user *)(p+4)))
+			return -EFAULT;
+
+		/*
+		 * Needs the console lock here. Note that lots of other calls
+		 * need fixing before the lock is actually useful!
+		 */
+		console_lock();
+		scrollfront(vc_cons[fg_console].d, lines);
+		console_unlock();
 		break;
 	case TIOCL_BLANKSCREEN:	/* until explicitly unblanked, not only poked */
 		console_lock();
@@ -3224,11 +3216,9 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
 		console_unlock();
 		break;
 	case TIOCL_BLANKEDSCREEN:
-		ret = console_blanked;
-		break;
+		return console_blanked;
 	default:
-		ret = -EINVAL;
-		break;
+		return -EINVAL;
 	}
 
 	return ret;
-- 
2.40.0