V4L/DVB (6323): V4L: cinergyT2, remove bad usage of ERESTARTSYS

cinergyT2, remove bad usage of ERESTARTSYS

test of cinergyt2->disconnect_pending doesn't ensure pending signal and so
ERESTARTSYS would reach userspace, which is not permitted. Change it to
EAGAIN.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/dvb/cinergyT2/cinergyT2.c

@@ -345,7 +345,9 @@ static int cinergyt2_start_feed(struct dvb_demux_feed *dvbdmxfeed)
 	struct dvb_demux *demux = dvbdmxfeed->demux;
 	struct cinergyt2 *cinergyt2 = demux->priv;
 
-	if (cinergyt2->disconnect_pending || mutex_lock_interruptible(&cinergyt2->sem))
+	if (cinergyt2->disconnect_pending)
+		return -EAGAIN;
+	if (mutex_lock_interruptible(&cinergyt2->sem))
 		return -ERESTARTSYS;
 
 	if (cinergyt2->streaming == 0)
@@ -361,7 +363,9 @@ static int cinergyt2_stop_feed(struct dvb_demux_feed *dvbdmxfeed)
 	struct dvb_demux *demux = dvbdmxfeed->demux;
 	struct cinergyt2 *cinergyt2 = demux->priv;
 
-	if (cinergyt2->disconnect_pending || mutex_lock_interruptible(&cinergyt2->sem))
+	if (cinergyt2->disconnect_pending)
+		return -EAGAIN;
+	if (mutex_lock_interruptible(&cinergyt2->sem))
 		return -ERESTARTSYS;
 
 	if (--cinergyt2->streaming == 0)
@@ -481,12 +485,16 @@ static int cinergyt2_open (struct inode *inode, struct file *file)
 {
 	struct dvb_device *dvbdev = file->private_data;
 	struct cinergyt2 *cinergyt2 = dvbdev->priv;
-	int err = -ERESTARTSYS;
+	int err = -EAGAIN;
 
-	if (cinergyt2->disconnect_pending || mutex_lock_interruptible(&cinergyt2->wq_sem))
+	if (cinergyt2->disconnect_pending)
+		goto out;
+	err = mutex_lock_interruptible(&cinergyt2->wq_sem);
+	if (err)
 		goto out;
 
-	if (mutex_lock_interruptible(&cinergyt2->sem))
+	err = mutex_lock_interruptible(&cinergyt2->sem);
+	if (err)
 		goto out_unlock1;
 
 	if ((err = dvb_generic_open(inode, file)))
@@ -550,7 +558,9 @@ static unsigned int cinergyt2_poll (struct file *file, struct poll_table_struct
 	struct cinergyt2 *cinergyt2 = dvbdev->priv;
 	unsigned int mask = 0;
 
-	if (cinergyt2->disconnect_pending || mutex_lock_interruptible(&cinergyt2->sem))
+	if (cinergyt2->disconnect_pending)
+		return -EAGAIN;
+	if (mutex_lock_interruptible(&cinergyt2->sem))
 		return -ERESTARTSYS;
 
 	poll_wait(file, &cinergyt2->poll_wq, wait);
@@ -625,7 +635,9 @@ static int cinergyt2_ioctl (struct inode *inode, struct file *file,
 		if (copy_from_user(&p, (void  __user*) arg, sizeof(p)))
 			return -EFAULT;
 
-		if (cinergyt2->disconnect_pending || mutex_lock_interruptible(&cinergyt2->sem))
+		if (cinergyt2->disconnect_pending)
+			return -EAGAIN;
+		if (mutex_lock_interruptible(&cinergyt2->sem))
 			return -ERESTARTSYS;
 
 		param->cmd = CINERGYT2_EP1_SET_TUNER_PARAMETERS;
@@ -996,7 +1008,9 @@ static int cinergyt2_suspend (struct usb_interface *intf, pm_message_t state)
 {
 	struct cinergyt2 *cinergyt2 = usb_get_intfdata (intf);
 
-	if (cinergyt2->disconnect_pending || mutex_lock_interruptible(&cinergyt2->wq_sem))
+	if (cinergyt2->disconnect_pending)
+		return -EAGAIN;
+	if (mutex_lock_interruptible(&cinergyt2->wq_sem))
 		return -ERESTARTSYS;
 
 	cinergyt2_suspend_rc(cinergyt2);
@@ -1017,16 +1031,18 @@ static int cinergyt2_resume (struct usb_interface *intf)
 {
 	struct cinergyt2 *cinergyt2 = usb_get_intfdata (intf);
 	struct dvbt_set_parameters_msg *param = &cinergyt2->param;
-	int err = -ERESTARTSYS;
+	int err = -EAGAIN;
 
-	if (cinergyt2->disconnect_pending || mutex_lock_interruptible(&cinergyt2->wq_sem))
+	if (cinergyt2->disconnect_pending)
+		goto out;
+	err = mutex_lock_interruptible(&cinergyt2->wq_sem);
+	if (err)
 		goto out;
 
-	if (mutex_lock_interruptible(&cinergyt2->sem))
+	err = mutex_lock_interruptible(&cinergyt2->sem);
+	if (err)
 		goto out_unlock1;
 
-	err = 0;
-
 	if (!cinergyt2->sleeping) {
 		cinergyt2_sleep(cinergyt2, 0);
 		cinergyt2_command(cinergyt2, (char *) param, sizeof(*param), NULL, 0);