Commit 9fd6418a authored by Figo.zhang's avatar Figo.zhang Committed by Mauro Carvalho Chehab
Browse files

V4L/DVB (12004): poll method lose race condition 



bttv-driver.c,cx23885-video.c,cx88-video.c: poll method lose race condition for capture video.

Signed-off-by: default avatarFigo.zhang <figo1802@gmail.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
parent 1c905a45

drivers/media/video/bt8xx/bttv-driver.c

+7 −4
Original line number Diff line number Diff line
@@ -3152,6 +3152,7 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait) 
	struct bttv_fh *fh = file->private_data;

	struct bttv_buffer *buf;

	enum v4l2_field field;

	unsigned int rc = POLLERR;



	if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {

		if (!check_alloc_btres(fh->btv,fh,RESOURCE_VBI))
@@ -3160,9 +3161,10 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait) 
	}



	if (check_btres(fh,RESOURCE_VIDEO_STREAM)) {

		mutex_lock(&fh->cap.vb_lock);

		/* streaming capture */

		if (list_empty(&fh->cap.stream))

			return POLLERR;

			goto err;

		buf = list_entry(fh->cap.stream.next,struct bttv_buffer,vb.stream);

	} else {

		/* read() capture */
@@ -3191,11 +3193,12 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait) 
	poll_wait(file, &buf->vb.done, wait);

	if (buf->vb.state == VIDEOBUF_DONE ||

	    buf->vb.state == VIDEOBUF_ERROR)

		return POLLIN|POLLRDNORM;

	return 0;

		rc =  POLLIN|POLLRDNORM;

	else

		rc = 0;

err:

	mutex_unlock(&fh->cap.vb_lock);

	return POLLERR;

	return rc;

}



static int bttv_open(struct file *file)

drivers/media/video/cx23885/cx23885-video.c

+10 −4
Original line number Diff line number Diff line
@@ -796,6 +796,7 @@ static unsigned int video_poll(struct file *file, 
{

	struct cx23885_fh *fh = file->private_data;

	struct cx23885_buffer *buf;

	unsigned int rc = POLLERR;



	if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {

		if (!res_get(fh->dev, fh, RESOURCE_VBI))
@@ -803,23 +804,28 @@ static unsigned int video_poll(struct file *file, 
		return videobuf_poll_stream(file, &fh->vbiq, wait);

	}



	mutex_lock(&fh->vidq.vb_lock);

	if (res_check(fh, RESOURCE_VIDEO)) {

		/* streaming capture */

		if (list_empty(&fh->vidq.stream))

			return POLLERR;

			goto done;

		buf = list_entry(fh->vidq.stream.next,

			struct cx23885_buffer, vb.stream);

	} else {

		/* read() capture */

		buf = (struct cx23885_buffer *)fh->vidq.read_buf;

		if (NULL == buf)

			return POLLERR;

			goto done;

	}

	poll_wait(file, &buf->vb.done, wait);

	if (buf->vb.state == VIDEOBUF_DONE ||

	    buf->vb.state == VIDEOBUF_ERROR)

		return POLLIN|POLLRDNORM;

	return 0;

		rc =  POLLIN|POLLRDNORM;

	else

		rc = 0;

done:

	mutex_unlock(&fh->vidq.vb_lock);

	return rc;

}



static int video_release(struct file *file)

drivers/media/video/cx88/cx88-video.c

+10 −4
Original line number Diff line number Diff line
@@ -869,6 +869,7 @@ video_poll(struct file *file, struct poll_table_struct *wait) 
{

	struct cx8800_fh *fh = file->private_data;

	struct cx88_buffer *buf;

	unsigned int rc = POLLERR;



	if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {

		if (!res_get(fh->dev,fh,RESOURCE_VBI))
@@ -876,22 +877,27 @@ video_poll(struct file *file, struct poll_table_struct *wait) 
		return videobuf_poll_stream(file, &fh->vbiq, wait);

	}



	mutex_lock(&fh->vidq.vb_lock);

	if (res_check(fh,RESOURCE_VIDEO)) {

		/* streaming capture */

		if (list_empty(&fh->vidq.stream))

			return POLLERR;

			goto done;

		buf = list_entry(fh->vidq.stream.next,struct cx88_buffer,vb.stream);

	} else {

		/* read() capture */

		buf = (struct cx88_buffer*)fh->vidq.read_buf;

		if (NULL == buf)

			return POLLERR;

			goto done;

	}

	poll_wait(file, &buf->vb.done, wait);

	if (buf->vb.state == VIDEOBUF_DONE ||

	    buf->vb.state == VIDEOBUF_ERROR)

		return POLLIN|POLLRDNORM;

	return 0;

		rc = POLLIN|POLLRDNORM;

	else

		rc = 0;

done:

	mutex_unlock(&fh->vidq.vb_lock);

	return rc;

}



static int video_release(struct file *file)

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