X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Ftty%2Fpty.c;h=bcec4c71a408cd60832d1f1bcf4fdc32e174c777;hb=2622d73e51acfe1dbeb21bf2299066bdead85163;hp=7f612c524224740451e4b18cd0618cef663c7692;hpb=dbfcd851a9ee0bf6952e538be75230b7c071dafb;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 7f612c524224..bcec4c71a408 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -178,21 +178,21 @@ static int pty_get_lock(struct tty_struct *tty, int __user *arg)
 /* Set the packet mode on a pty */
 static int pty_set_pktmode(struct tty_struct *tty, int __user *arg)
 {
-	unsigned long flags;
 	int pktmode;
 
 	if (get_user(pktmode, arg))
 		return -EFAULT;
 
-	spin_lock_irqsave(&tty->ctrl_lock, flags);
+	spin_lock_irq(&tty->ctrl_lock);
 	if (pktmode) {
 		if (!tty->packet) {
-			tty->packet = 1;
 			tty->link->ctrl_status = 0;
+			smp_mb();
+			tty->packet = 1;
 		}
 	} else
 		tty->packet = 0;
-	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+	spin_unlock_irq(&tty->ctrl_lock);
 
 	return 0;
 }
@@ -221,16 +221,15 @@ static int pty_signal(struct tty_struct *tty, int sig)
 static void pty_flush_buffer(struct tty_struct *tty)
 {
 	struct tty_struct *to = tty->link;
-	unsigned long flags;
 
 	if (!to)
 		return;
 	/* tty_buffer_flush(to); FIXME */
 	if (to->packet) {
-		spin_lock_irqsave(&tty->ctrl_lock, flags);
+		spin_lock_irq(&tty->ctrl_lock);
 		tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
 		wake_up_interruptible(&to->read_wait);
-		spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+		spin_unlock_irq(&tty->ctrl_lock);
 	}
 }
 
@@ -259,8 +258,6 @@ out:
 static void pty_set_termios(struct tty_struct *tty,
 					struct ktermios *old_termios)
 {
-	unsigned long flags;
-
 	/* See if packet mode change of state. */
 	if (tty->link && tty->link->packet) {
 		int extproc = (old_termios->c_lflag & EXTPROC) |
@@ -272,7 +269,7 @@ static void pty_set_termios(struct tty_struct *tty,
 				STOP_CHAR(tty) == '\023' &&
 				START_CHAR(tty) == '\021');
 		if ((old_flow != new_flow) || extproc) {
-			spin_lock_irqsave(&tty->ctrl_lock, flags);
+			spin_lock_irq(&tty->ctrl_lock);
 			if (old_flow != new_flow) {
 				tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
 				if (new_flow)
@@ -282,7 +279,7 @@ static void pty_set_termios(struct tty_struct *tty,
 			}
 			if (extproc)
 				tty->ctrl_status |= TIOCPKT_IOCTL;
-			spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+			spin_unlock_irq(&tty->ctrl_lock);
 			wake_up_interruptible(&tty->link->read_wait);
 		}
 	}
@@ -343,26 +340,26 @@ static void pty_start(struct tty_struct *tty)
 {
 	unsigned long flags;
 
-	spin_lock_irqsave(&tty->ctrl_lock, flags);
 	if (tty->link && tty->link->packet) {
+		spin_lock_irqsave(&tty->ctrl_lock, flags);
 		tty->ctrl_status &= ~TIOCPKT_STOP;
 		tty->ctrl_status |= TIOCPKT_START;
+		spin_unlock_irqrestore(&tty->ctrl_lock, flags);
 		wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
 	}
-	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
 }
 
 static void pty_stop(struct tty_struct *tty)
 {
 	unsigned long flags;
 
-	spin_lock_irqsave(&tty->ctrl_lock, flags);
 	if (tty->link && tty->link->packet) {
+		spin_lock_irqsave(&tty->ctrl_lock, flags);
 		tty->ctrl_status &= ~TIOCPKT_START;
 		tty->ctrl_status |= TIOCPKT_STOP;
+		spin_unlock_irqrestore(&tty->ctrl_lock, flags);
 		wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
 	}
-	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
 }
 
 /**