1 files changed, 18 insertions, 2 deletions

diff --git a/drivers/media/video/vivi.c b/drivers/media/video/vivi.c
index 0e623179f8a5..02a232768e3b 100644
--- a/drivers/media/video/vivi.c
+++ b/drivers/media/video/vivi.c
@@ -164,6 +164,7 @@ struct vivi_dev {
 
         struct mutex               lock;
         spinlock_t                 slock;
+        struct mutex               mutex;
 
         int                        users;
 
@@ -1036,6 +1037,7 @@ static int vivi_open(struct inode *inode, struct file *file)
         struct vivi_dev *dev;
         struct vivi_fh *fh;
         int i;
+        int retval = 0;
 
         printk(KERN_DEBUG "vivi: open called (minor=%d)\n", minor);
 
@@ -1045,9 +1047,15 @@ static int vivi_open(struct inode *inode, struct file *file)
         return -ENODEV;
 
 found:
-        /* If more than one user, mutex should be added */
+        mutex_lock(&dev->mutex);
         dev->users++;
 
+        if (dev->users > 1) {
+                dev->users--;
+                retval = -EBUSY;
+                goto unlock;
+        }
+
         dprintk(dev, 1, "open minor=%d type=%s users=%d\n", minor,
                 v4l2_type_names[V4L2_BUF_TYPE_VIDEO_CAPTURE], dev->users);
 
@@ -1055,8 +1063,13 @@ found:
         fh = kzalloc(sizeof(*fh), GFP_KERNEL);
         if (NULL == fh) {
                 dev->users--;
-                return -ENOMEM;
+                retval = -ENOMEM;
+                goto unlock;
         }
+unlock:
+        mutex_unlock(&dev->mutex);
+        if (retval)
+                return retval;
 
         file->private_data = fh;
         fh->dev      = dev;
@@ -1128,7 +1141,9 @@ static int vivi_close(struct inode *inode, struct file *file)
 
         kfree(fh);
 
+        mutex_lock(&dev->mutex);
         dev->users--;
+        mutex_unlock(&dev->mutex);
 
         dprintk(dev, 1, "close called (minor=%d, users=%d)\n",
                 minor, dev->users);
@@ -1243,6 +1258,7 @@ static int __init vivi_init(void)
                 /* initialize locks */
                 mutex_init(&dev->lock);
                 spin_lock_init(&dev->slock);
+                mutex_init(&dev->mutex);
 
                 dev->vidq.timeout.function = vivi_vid_timeout;
                 dev->vidq.timeout.data     = (unsigned long)dev;