RE: [PATCH 2/5] ipu3-cio2: Serialise access to pad format

["Cao, Bingbu" <bingbu.cao@intel.com>]

Sakari, thank you for the patch.

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

________________________
BRs,  
Bingbu Cao                          


> -----Original Message-----
> From: Sakari Ailus <sakari.ailus@linux.intel.com>
> Sent: Friday, October 9, 2020 11:08 PM
> To: linux-media@vger.kernel.org
> Cc: Tsuchiya Yuto <kitakar@gmail.com>; Cao, Bingbu <bingbu.cao@intel.com>;
> Zhi, Yong <yong.zhi@intel.com>; Qiu, Tian Shu <tian.shu.qiu@intel.com>;
> laurent.pinchart@ideasonboard.com
> Subject: [PATCH 2/5] ipu3-cio2: Serialise access to pad format
> 
> Pad format can be accessed from user space. Serialise access to it.
> 
> Fixes: c2a6a07afe4a ("media: intel-ipu3: cio2: add new MIPI-CSI2 driver")
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
>  drivers/media/pci/intel/ipu3/ipu3-cio2.c | 11 +++++++++++
> drivers/media/pci/intel/ipu3/ipu3-cio2.h |  1 +
>  2 files changed, 12 insertions(+)
> 
> diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> index afa472026ba4..9c7b527a8800 100644
> --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> @@ -1233,11 +1233,15 @@ static int cio2_subdev_get_fmt(struct v4l2_subdev
> *sd,  {
>  	struct cio2_queue *q = container_of(sd, struct cio2_queue, subdev);
> 
> +	mutex_lock(&q->subdev_lock);
> +
>  	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
>  		fmt->format = *v4l2_subdev_get_try_format(sd, cfg, fmt->pad);
>  	else
>  		fmt->format = q->subdev_fmt;
> 
> +	mutex_unlock(&q->subdev_lock);
> +
>  	return 0;
>  }
> 
> @@ -1261,6 +1265,8 @@ static int cio2_subdev_set_fmt(struct v4l2_subdev *sd,
>  	if (fmt->pad == CIO2_PAD_SOURCE)
>  		return cio2_subdev_get_fmt(sd, cfg, fmt);
> 
> +	mutex_lock(&q->subdev_lock);
> +
>  	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
>  		*v4l2_subdev_get_try_format(sd, cfg, fmt->pad) = fmt->format;
>  	} else {
> @@ -1271,6 +1277,8 @@ static int cio2_subdev_set_fmt(struct v4l2_subdev *sd,
>  		fmt->format = q->subdev_fmt;
>  	}
> 
> +	mutex_unlock(&q->subdev_lock);
> +
>  	return 0;
>  }
> 
> @@ -1529,6 +1537,7 @@ static int cio2_queue_init(struct cio2_device *cio2,
> struct cio2_queue *q)
> 
>  	/* Initialize miscellaneous variables */
>  	mutex_init(&q->lock);
> +	mutex_init(&q->subdev_lock);
> 
>  	/* Initialize formats to default values */
>  	fmt = &q->subdev_fmt;
> @@ -1646,6 +1655,7 @@ static int cio2_queue_init(struct cio2_device *cio2,
> struct cio2_queue *q)
>  	cio2_fbpt_exit(q, &cio2->pci_dev->dev);
>  fail_fbpt:
>  	mutex_destroy(&q->lock);
> +	mutex_destroy(&q->subdev_lock);
> 
>  	return r;
>  }
> @@ -1658,6 +1668,7 @@ static void cio2_queue_exit(struct cio2_device *cio2,
> struct cio2_queue *q)
>  	media_entity_cleanup(&q->subdev.entity);
>  	cio2_fbpt_exit(q, &cio2->pci_dev->dev);
>  	mutex_destroy(&q->lock);
> +	mutex_destroy(&q->subdev_lock);
>  }
> 
>  static int cio2_queues_init(struct cio2_device *cio2) diff --git
> a/drivers/media/pci/intel/ipu3/ipu3-cio2.h
> b/drivers/media/pci/intel/ipu3/ipu3-cio2.h
> index 549b08f88f0c..146492383aa5 100644
> --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.h
> +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.h
> @@ -335,6 +335,7 @@ struct cio2_queue {
> 
>  	/* Subdev, /dev/v4l-subdevX */
>  	struct v4l2_subdev subdev;
> +	struct mutex subdev_lock; /* Serialise acces to subdev_fmt field */
>  	struct media_pad subdev_pads[CIO2_PADS];
>  	struct v4l2_mbus_framefmt subdev_fmt;
>  	atomic_t frame_sequence;
> --
> 2.27.0