V4L/DVB (7491): vivi: make vivi openable only once

vivi currently doesn't have the infrastructure to handle being opened more than
one time and will crash if it is.  So, make it openable only once.

Signed-off-by: Brandon Philips <bphilips@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Brandon Philips 2008-04-02 18:10:59 -03:00 committed by Mauro Carvalho Chehab
parent cbcb565f74
commit aa9dbac426

View File

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