From: "Figo.zhang" <figo1802@gmail.com>
To: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: linux-media@vger.kernel.org, kraxel@bytesex.org,
"Hans Verkuil" <hverkuil@xs4all.nl>,
"Oldřich Jedlička" <oldium.pro@seznam.cz>
Subject: [PATCH] bttv-driver.c :poll method lose race condition for capture video
Date: Sun, 31 May 2009 14:32:18 +0800 [thread overview]
Message-ID: <1243751538.3425.6.camel@myhost> (raw)
bttv-driver.c,cx23885-video.c,cx88-video.c: poll method lose race condition for capture video.
Signed-off-by: Figo.zhang <figo1802@gmail.com>
---
drivers/media/video/bt8xx/bttv-driver.c | 7 +++++--
drivers/media/video/cx23885/cx23885-video.c | 15 +++++++++++----
drivers/media/video/cx88/cx88-video.c | 13 ++++++++++---
3 files changed, 26 insertions(+), 9 deletions(-)
diff --git a/drivers/media/video/bt8xx/bttv-driver.c b/drivers/media/video/bt8xx/bttv-driver.c
index 23b7499..9cadfcc 100644
--- a/drivers/media/video/bt8xx/bttv-driver.c
+++ b/drivers/media/video/bt8xx/bttv-driver.c
@@ -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 = 0;
if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {
if (!check_alloc_btres(fh->btv,fh,RESOURCE_VBI))
@@ -3160,6 +3161,7 @@ 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;
@@ -3191,8 +3193,9 @@ 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;
+ mutex_unlock(&fh->cap.vb_lock);
+ return rc;
err:
mutex_unlock(&fh->cap.vb_lock);
return POLLERR;
diff --git a/drivers/media/video/cx23885/cx23885-video.c b/drivers/media/video/cx23885/cx23885-video.c
index 68068c6..386ad86 100644
--- a/drivers/media/video/cx23885/cx23885-video.c
+++ b/drivers/media/video/cx23885/cx23885-video.c
@@ -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 = 0;
if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {
if (!res_get(fh->dev, fh, RESOURCE_VBI))
@@ -803,23 +804,29 @@ 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 err;
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 err;
}
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;
+ mutex_unlock(&fh->vidq.vb_lock);
+ return rc;
+
+err:
+ mutex_unlock(&fh->vidq.vb_lock);
+ return POLLERR;
}
static int video_release(struct file *file)
diff --git a/drivers/media/video/cx88/cx88-video.c b/drivers/media/video/cx88/cx88-video.c
index b993d42..f778d15 100644
--- a/drivers/media/video/cx88/cx88-video.c
+++ b/drivers/media/video/cx88/cx88-video.c
@@ -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 = 0;
if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {
if (!res_get(fh->dev,fh,RESOURCE_VBI))
@@ -876,22 +877,28 @@ 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 err;
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 err;
}
poll_wait(file, &buf->vb.done, wait);
if (buf->vb.state == VIDEOBUF_DONE ||
buf->vb.state == VIDEOBUF_ERROR)
- return POLLIN|POLLRDNORM;
+ rc = POLLIN|POLLRDNORM;
+ mutex_unlock(&fh->vidq.vb_lock);
return 0;
+
+err:
+ mutex_unlock(&fh->vidq.vb_lock);
+ return POLLERR;
}
static int video_release(struct file *file)
next reply other threads:[~2009-05-31 6:32 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-31 6:32 Figo.zhang [this message]
2009-05-31 21:29 ` [PATCH] bttv-driver.c :poll method lose race condition for capture video Trent Piepho
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