[PATCH 22/24] drm: Nerf the preclose callback for modern drivers

[Daniel Vetter]

On Wed, Mar 08, 2017 at 03:12:55PM +0100, Daniel Vetter wrote:
> With all drivers converted there's only legacy dri1 drivers using it.
> Not going to touch those, instead just hide it like we've done with
> other dri1 driver hooks like firstopen.
> 
> In all this I didn't find any real reason why we'd needed 2 hooks, and
> having symmetry between open and close just appeases my OCD better.
> Yeah, someone else could do an s/postclose/close/, but that's for
> someone who understands cocci. And maybe after this series is reviewed
> and landed, to avoid patch-regen churn.
> 
> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>

>From irc:

Acked-by: Dave Airlie <airlied at gmail.com>
> ---
>  drivers/gpu/drm/drm_file.c |  8 ++++----
>  include/drm/drm_drv.h      | 23 ++---------------------
>  2 files changed, 6 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
> index a8813a1115dc..f8483fc6d3d7 100644
> --- a/drivers/gpu/drm/drm_file.c
> +++ b/drivers/gpu/drm/drm_file.c
> @@ -350,9 +350,8 @@ void drm_lastclose(struct drm_device * dev)
>   *
>   * This function must be used by drivers as their &file_operations.release
>   * method. It frees any resources associated with the open file, and calls the
> - * &drm_driver.preclose and &drm_driver.lastclose driver callbacks. If this is
> - * the last open file for the DRM device also proceeds to call the
> - * &drm_driver.lastclose driver callback.
> + * &drm_driver.lastclose driver callback. If this is the last open file for the
> + * DRM device also proceeds to call the &drm_driver.lastclose driver callback.
>   *
>   * RETURNS:
>   *
> @@ -372,7 +371,8 @@ int drm_release(struct inode *inode, struct file *filp)
>  	list_del(&file_priv->lhead);
>  	mutex_unlock(&dev->filelist_mutex);
>  
> -	if (dev->driver->preclose)
> +	if (drm_core_check_feature(dev, DRIVER_LEGACY) &&
> +	    dev->driver->preclose)
>  		dev->driver->preclose(dev, file_priv);
>  
>  	/* ========================================================
> diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
> index 8f900fb30275..fde343e0d581 100644
> --- a/include/drm/drm_drv.h
> +++ b/include/drm/drm_drv.h
> @@ -104,23 +104,6 @@ struct drm_driver {
>  	int (*open) (struct drm_device *, struct drm_file *);
>  
>  	/**
> -	 * @preclose:
> -	 *
> -	 * One of the driver callbacks when a new &struct drm_file is closed.
> -	 * Useful for tearing down driver-private data structures allocated in
> -	 * @open like buffer allocators, execution contexts or similar things.
> -	 *
> -	 * Since the display/modeset side of DRM can only be owned by exactly
> -	 * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
> -	 * there should never be a need to tear down any modeset related
> -	 * resources in this callback. Doing so would be a driver design bug.
> -	 *
> -	 * FIXME: It is not really clear why there's both @preclose and
> -	 * @postclose. Without a really good reason, use @postclose only.
> -	 */
> -	void (*preclose) (struct drm_device *, struct drm_file *file_priv);
> -
> -	/**
>  	 * @postclose:
>  	 *
>  	 * One of the driver callbacks when a new &struct drm_file is closed.
> @@ -131,9 +114,6 @@ struct drm_driver {
>  	 * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
>  	 * there should never be a need to tear down any modeset related
>  	 * resources in this callback. Doing so would be a driver design bug.
> -	 *
> -	 * FIXME: It is not really clear why there's both @preclose and
> -	 * @postclose. Without a really good reason, use @postclose only.
>  	 */
>  	void (*postclose) (struct drm_device *, struct drm_file *);
>  
> @@ -150,7 +130,7 @@ struct drm_driver {
>  	 * state changes, e.g. in conjunction with the :ref:`vga_switcheroo`
>  	 * infrastructure.
>  	 *
> -	 * This is called after @preclose and @postclose have been called.
> +	 * This is called after @postclose hook has been called.
>  	 *
>  	 * NOTE:
>  	 *
> @@ -516,6 +496,7 @@ struct drm_driver {
>  	/* List of devices hanging off this driver with stealth attach. */
>  	struct list_head legacy_dev_list;
>  	int (*firstopen) (struct drm_device *);
> +	void (*preclose) (struct drm_device *, struct drm_file *file_priv);
>  	int (*dma_ioctl) (struct drm_device *dev, void *data, struct drm_file *file_priv);
>  	int (*dma_quiescent) (struct drm_device *);
>  	int (*context_dtor) (struct drm_device *dev, int context);
> -- 
> 2.11.0
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch