diff options
| author | Brandon Philips <bphilips@suse.de> | 2007-09-27 20:55:17 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@infradead.org> | 2007-10-10 00:03:05 -0300 |
| commit | ba32bd95d431525ad2ffac97cadf9ee40b63939e (patch) | |
| tree | edb0f38f00c980bd4c95bd82093c8cfad9653a26 /drivers/media | |
| parent | 85c7c70bc241d506dffc1879158f77f8aac69734 (diff) | |
V4L/DVB (6275): V4L: vivi.c remove the "resource" locking
The "resource" locking in vivi isn't needed since
streamon/streamoff/read_stream do mutual exclusion using
q->reading/q->streaming.
Plus it is sort of broken:
a) res_locked() use in vivi_read() is racey.
b) res_free() calls mutex_lock twice causing streamoff to break
Signed-off-by: Brandon Philips <bphilips@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/video/vivi.c | 48 |
1 files changed, 4 insertions, 44 deletions
diff --git a/drivers/media/video/vivi.c b/drivers/media/video/vivi.c index cdef622f6b3..82755091648 100644 --- a/drivers/media/video/vivi.c +++ b/drivers/media/video/vivi.c @@ -170,7 +170,6 @@ struct vivi_dev { int users; /* various device info */ - unsigned int resources; struct video_device vfd; struct vivi_dmaqueue vidq; @@ -727,40 +726,6 @@ static struct videobuf_queue_ops vivi_video_qops = { }; /* ------------------------------------------------------------------ - IOCTL handling - ------------------------------------------------------------------*/ - - -static int res_get(struct vivi_dev *dev, struct vivi_fh *fh) -{ - /* is it free? */ - mutex_lock(&dev->lock); - if (dev->resources) { - /* no, someone else uses it */ - mutex_unlock(&dev->lock); - return 0; - } - /* it's free, grab it */ - dev->resources =1; - dprintk(1,"res: get\n"); - mutex_unlock(&dev->lock); - return 1; -} - -static int res_locked(struct vivi_dev *dev) -{ - return (dev->resources); -} - -static void res_free(struct vivi_dev *dev, struct vivi_fh *fh) -{ - mutex_lock(&dev->lock); - dev->resources = 0; - dprintk(1,"res: put\n"); - mutex_lock(&dev->lock); -} - -/* ------------------------------------------------------------------ IOCTL vidioc handling ------------------------------------------------------------------*/ static int vidioc_querycap (struct file *file, void *priv, @@ -913,9 +878,7 @@ static int vidioc_streamon(struct file *file, void *priv, enum v4l2_buf_type i) if (i != fh->type) return -EINVAL; - if (!res_get(dev,fh)) - return -EBUSY; - return (videobuf_streamon(&fh->vb_vidq)); + return videobuf_streamon(&fh->vb_vidq); } static int vidioc_streamoff(struct file *file, void *priv, enum v4l2_buf_type i) @@ -928,10 +891,7 @@ static int vidioc_streamoff(struct file *file, void *priv, enum v4l2_buf_type i) if (i != fh->type) return -EINVAL; - videobuf_streamoff(&fh->vb_vidq); - res_free(dev,fh); - - return (0); + return videobuf_streamoff(&fh->vb_vidq); } static int vidioc_s_std (struct file *file, void *priv, v4l2_std_id *i) @@ -1096,10 +1056,10 @@ static ssize_t vivi_read(struct file *file, char __user *data, size_t count, loff_t *ppos) { struct vivi_fh *fh = file->private_data; + struct vivi_dev *dev = fh->dev; + struct videobuf_queue *q = &fh->vb_vidq; if (fh->type==V4L2_BUF_TYPE_VIDEO_CAPTURE) { - if (res_locked(fh->dev)) - return -EBUSY; return videobuf_read_stream(&fh->vb_vidq, data, count, ppos, 0, file->f_flags & O_NONBLOCK); } |