[PATCH 0/2] Trivial CIO2 patches

[PATCH 0/2] Trivial CIO2 patches

[Sakari Ailus]

Hi,

Here are two simple cio2 patches. Slightly safer module removal plus a
cleanup.

Sakari Ailus (2):
  ipu3-cio2: Unregister device nodes first, then release resources
  ipu3-cio2: Use cio2_queues_exit

 drivers/media/pci/intel/ipu3/ipu3-cio2.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

-- 
2.11.0

[PATCH 1/2] ipu3-cio2: Unregister device nodes first, then release resources

[Sakari Ailus]

While there are issues related to object lifetime management, unregister
the media device first, followed immediately by other device nodes when
the driver is being unbound. Only then the resources needed by the driver
may be released. This is slightly safer.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 drivers/media/pci/intel/ipu3/ipu3-cio2.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
index 452eb9b42140..723022ef3662 100644
--- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
+++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
@@ -1846,12 +1846,12 @@ static void cio2_pci_remove(struct pci_dev *pci_dev)
 	struct cio2_device *cio2 = pci_get_drvdata(pci_dev);
 	unsigned int i;
 
+	media_device_unregister(&cio2->media_dev);
 	cio2_notifier_exit(cio2);
-	cio2_fbpt_exit_dummy(cio2);
 	for (i = 0; i < CIO2_QUEUES; i++)
 		cio2_queue_exit(cio2, &cio2->queue[i]);
+	cio2_fbpt_exit_dummy(cio2);
 	v4l2_device_unregister(&cio2->v4l2_dev);
-	media_device_unregister(&cio2->media_dev);
 	media_device_cleanup(&cio2->media_dev);
 	mutex_destroy(&cio2->lock);
 }
-- 
2.11.0

[PATCH 2/2] ipu3-cio2: Use cio2_queues_exit

[Sakari Ailus]

The ipu3-cio2 driver has a function to tear down video devices as well as
the associated video buffer queues. Use it.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 drivers/media/pci/intel/ipu3/ipu3-cio2.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
index 723022ef3662..447baaebca44 100644
--- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
+++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
@@ -1844,12 +1844,10 @@ static int cio2_pci_probe(struct pci_dev *pci_dev,
 static void cio2_pci_remove(struct pci_dev *pci_dev)
 {
 	struct cio2_device *cio2 = pci_get_drvdata(pci_dev);
-	unsigned int i;
 
 	media_device_unregister(&cio2->media_dev);
 	cio2_notifier_exit(cio2);
-	for (i = 0; i < CIO2_QUEUES; i++)
-		cio2_queue_exit(cio2, &cio2->queue[i]);
+	cio2_queues_exit(cio2);
 	cio2_fbpt_exit_dummy(cio2);
 	v4l2_device_unregister(&cio2->v4l2_dev);
 	media_device_cleanup(&cio2->media_dev);
-- 
2.11.0

Re: [PATCH 1/2] ipu3-cio2: Unregister device nodes first, then release resources

[Bing Bu Cao]

Tested-by: Bingbu Cao <bingbu.cao@intel.com>
Reviewed-by: Bingbu Cao <bingbu.cao@intel.com>

On 10/10/2018 04:32 PM, Sakari Ailus wrote:
> While there are issues related to object lifetime management, unregister
> the media device first, followed immediately by other device nodes when
> the driver is being unbound. Only then the resources needed by the driver
> may be released. This is slightly safer.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
>  drivers/media/pci/intel/ipu3/ipu3-cio2.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> index 452eb9b42140..723022ef3662 100644
> --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> @@ -1846,12 +1846,12 @@ static void cio2_pci_remove(struct pci_dev *pci_dev)
>  	struct cio2_device *cio2 = pci_get_drvdata(pci_dev);
>  	unsigned int i;
>  
> +	media_device_unregister(&cio2->media_dev);
>  	cio2_notifier_exit(cio2);
> -	cio2_fbpt_exit_dummy(cio2);
>  	for (i = 0; i < CIO2_QUEUES; i++)
>  		cio2_queue_exit(cio2, &cio2->queue[i]);
> +	cio2_fbpt_exit_dummy(cio2);
>  	v4l2_device_unregister(&cio2->v4l2_dev);
> -	media_device_unregister(&cio2->media_dev);
>  	media_device_cleanup(&cio2->media_dev);
>  	mutex_destroy(&cio2->lock);
>  }

Re: [PATCH 2/2] ipu3-cio2: Use cio2_queues_exit

[Bing Bu Cao]

Tested-by: Bingbu Cao <bingbu.cao@intel.com>
Reviewed-by: Bingbu Cao <bingbu.cao@intel.com>

On 10/10/2018 04:32 PM, Sakari Ailus wrote:
> The ipu3-cio2 driver has a function to tear down video devices as well as
> the associated video buffer queues. Use it.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
>  drivers/media/pci/intel/ipu3/ipu3-cio2.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> index 723022ef3662..447baaebca44 100644
> --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> @@ -1844,12 +1844,10 @@ static int cio2_pci_probe(struct pci_dev *pci_dev,
>  static void cio2_pci_remove(struct pci_dev *pci_dev)
>  {
>  	struct cio2_device *cio2 = pci_get_drvdata(pci_dev);
> -	unsigned int i;
>  
>  	media_device_unregister(&cio2->media_dev);
>  	cio2_notifier_exit(cio2);
> -	for (i = 0; i < CIO2_QUEUES; i++)
> -		cio2_queue_exit(cio2, &cio2->queue[i]);
> +	cio2_queues_exit(cio2);
>  	cio2_fbpt_exit_dummy(cio2);
>  	v4l2_device_unregister(&cio2->v4l2_dev);
>  	media_device_cleanup(&cio2->media_dev);

Re: [PATCH 2/2] ipu3-cio2: Use cio2_queues_exit

[Sakari Ailus]

On Thu, Oct 11, 2018 at 05:16:30PM +0800, Bing Bu Cao wrote:
> Tested-by: Bingbu Cao <bingbu.cao@intel.com>
> Reviewed-by: Bingbu Cao <bingbu.cao@intel.com>

Thanks!!

-- 
Sakari Ailus
sakari.ailus@linux.intel.com

Re: [PATCH 1/2] ipu3-cio2: Unregister device nodes first, then release resources

[Bing Bu Cao]

On 10/10/2018 04:32 PM, Sakari Ailus wrote:
> While there are issues related to object lifetime management, unregister
> the media device first, followed immediately by other device nodes when
> the driver is being unbound. Only then the resources needed by the driver
> may be released. This is slightly safer.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
>  drivers/media/pci/intel/ipu3/ipu3-cio2.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> index 452eb9b42140..723022ef3662 100644
> --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> @@ -1846,12 +1846,12 @@ static void cio2_pci_remove(struct pci_dev *pci_dev)
>  	struct cio2_device *cio2 = pci_get_drvdata(pci_dev);
>  	unsigned int i;
>  
> +	media_device_unregister(&cio2->media_dev);
>  	cio2_notifier_exit(cio2);
> -	cio2_fbpt_exit_dummy(cio2);
>  	for (i = 0; i < CIO2_QUEUES; i++)
>  		cio2_queue_exit(cio2, &cio2->queue[i]);
> +	cio2_fbpt_exit_dummy(cio2);
Hi, Sakari,
The fbpt dummy pages cleanup does not matter much before/after queues
exit, right?
>  	v4l2_device_unregister(&cio2->v4l2_dev);
> -	media_device_unregister(&cio2->media_dev);
>  	media_device_cleanup(&cio2->media_dev);
>  	mutex_destroy(&cio2->lock);
>  }

Re: [PATCH 1/2] ipu3-cio2: Unregister device nodes first, then release resources

[Sakari Ailus]

Hi Bingbu,

On Mon, Oct 15, 2018 at 03:15:05PM +0800, Bing Bu Cao wrote:
> 
> On 10/10/2018 04:32 PM, Sakari Ailus wrote:
> > While there are issues related to object lifetime management, unregister
> > the media device first, followed immediately by other device nodes when
> > the driver is being unbound. Only then the resources needed by the driver
> > may be released. This is slightly safer.
> >
> > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> > ---
> >  drivers/media/pci/intel/ipu3/ipu3-cio2.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> > index 452eb9b42140..723022ef3662 100644
> > --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> > +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> > @@ -1846,12 +1846,12 @@ static void cio2_pci_remove(struct pci_dev *pci_dev)
> >  	struct cio2_device *cio2 = pci_get_drvdata(pci_dev);
> >  	unsigned int i;
> >  
> > +	media_device_unregister(&cio2->media_dev);
> >  	cio2_notifier_exit(cio2);
> > -	cio2_fbpt_exit_dummy(cio2);
> >  	for (i = 0; i < CIO2_QUEUES; i++)
> >  		cio2_queue_exit(cio2, &cio2->queue[i]);
> > +	cio2_fbpt_exit_dummy(cio2);
> Hi, Sakari,
> The fbpt dummy pages cleanup does not matter much before/after queues
> exit, right?

cio2_queue_exit() will unregister the video device and the video buffer
queue. Up to this point it's possible to open the video device and start
streaming on it. While this patch does not fully address the issue it makes
it a slightly lesser issue.

> >  	v4l2_device_unregister(&cio2->v4l2_dev);
> > -	media_device_unregister(&cio2->media_dev);
> >  	media_device_cleanup(&cio2->media_dev);
> >  	mutex_destroy(&cio2->lock);
> >  }
> 

-- 
Sakari Ailus
sakari.ailus@linux.intel.com

Re: [PATCH 1/2] ipu3-cio2: Unregister device nodes first, then release resources

[Bing Bu Cao]

On 10/15/2018 04:39 PM, Sakari Ailus wrote:
> Hi Bingbu,
>
> On Mon, Oct 15, 2018 at 03:15:05PM +0800, Bing Bu Cao wrote:
>> On 10/10/2018 04:32 PM, Sakari Ailus wrote:
>>> While there are issues related to object lifetime management, unregister
>>> the media device first, followed immediately by other device nodes when
>>> the driver is being unbound. Only then the resources needed by the driver
>>> may be released. This is slightly safer.
>>>
>>> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
>>> ---
>>>  drivers/media/pci/intel/ipu3/ipu3-cio2.c | 4 ++--
>>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
>>> index 452eb9b42140..723022ef3662 100644
>>> --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
>>> +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
>>> @@ -1846,12 +1846,12 @@ static void cio2_pci_remove(struct pci_dev *pci_dev)
>>>  	struct cio2_device *cio2 = pci_get_drvdata(pci_dev);
>>>  	unsigned int i;
>>>  
>>> +	media_device_unregister(&cio2->media_dev);
>>>  	cio2_notifier_exit(cio2);
>>> -	cio2_fbpt_exit_dummy(cio2);
>>>  	for (i = 0; i < CIO2_QUEUES; i++)
>>>  		cio2_queue_exit(cio2, &cio2->queue[i]);
>>> +	cio2_fbpt_exit_dummy(cio2);
>> Hi, Sakari,
>> The fbpt dummy pages cleanup does not matter much before/after queues
>> exit, right?
> cio2_queue_exit() will unregister the video device and the video buffer
> queue. Up to this point it's possible to open the video device and start
> streaming on it. While this patch does not fully address the issue it makes
> it a slightly lesser issue.
Okay, thanks for your explanation.
>>>  	v4l2_device_unregister(&cio2->v4l2_dev);
>>> -	media_device_unregister(&cio2->media_dev);
>>>  	media_device_cleanup(&cio2->media_dev);
>>>  	mutex_destroy(&cio2->lock);
>>>  }