Re: [PATCH 2/6] drm: Refactor setplane to allow internal use (v3)

["G, Pallavi" <pallavi.g@intel.com>]

On Tue, 2014-06-10 at 08:28 -0700, Matt Roper wrote:
> Refactor DRM setplane code into a new setplane_internal() function that
> takes DRM objects directly as parameters rather than looking them up by
> ID.  We'll use this in a future patch when we implement legacy cursor
> ioctls on top of the universal plane interface.
> 
> v3:
>  - Move integer overflow checking from setplane_internal to setplane
>    ioctl.  The upcoming legacy cursor support via universal planes needs
>    to maintain current cursor ioctl semantics and not return error for
>    these extreme values (found via intel-gpu-tools kms_cursor_crc test).
> v2:
>  - Allow planes to be disabled without a valid crtc again (and add
>    mention of this to setplane's kerneldoc, since it doesn't seem to be
>    mentioned anywhere else).
>  - Reformat some parameter line wrap
> 
> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
> ---
>  drivers/gpu/drm/drm_crtc.c | 176 ++++++++++++++++++++++++++-------------------
>  1 file changed, 102 insertions(+), 74 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index 5a88267..27eae03 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -2122,45 +2122,32 @@ out:
>  	return ret;
>  }
>  
> -/**
> - * drm_mode_setplane - configure a plane's configuration
> - * @dev: DRM device
> - * @data: ioctl data*
> - * @file_priv: DRM file info
> +/*
> + * setplane_internal - setplane handler for internal callers
>   *
> - * Set plane configuration, including placement, fb, scaling, and other factors.
> - * Or pass a NULL fb to disable.
> + * Note that we assume an extra reference has already been taken on fb.  If the
> + * update fails, this reference will be dropped before return; if it succeeds,
> + * the previous framebuffer (if any) will be unreferenced instead.
>   *
> - * Returns:
> - * Zero on success, errno on failure.
> + * src_{x,y,w,h} are provided in 16.16 fixed point format
>   */
> -int drm_mode_setplane(struct drm_device *dev, void *data,
> -		      struct drm_file *file_priv)
> +static int setplane_internal(struct drm_crtc *crtc,
> +			     struct drm_plane *plane,
> +			     struct drm_framebuffer *fb,
> +			     int32_t crtc_x, int32_t crtc_y,
> +			     uint32_t crtc_w, uint32_t crtc_h,
> +			     /* src_{x,y,w,h} values are 16.16 fixed point */
> +			     uint32_t src_x, uint32_t src_y,
> +			     uint32_t src_w, uint32_t src_h)
>  {
> -	struct drm_mode_set_plane *plane_req = data;
> -	struct drm_plane *plane;
> -	struct drm_crtc *crtc;
> -	struct drm_framebuffer *fb = NULL, *old_fb = NULL;
> +	struct drm_device *dev = crtc->dev;
> +	struct drm_framebuffer *old_fb = NULL;
>  	int ret = 0;
>  	unsigned int fb_width, fb_height;
>  	int i;
>  
> -	if (!drm_core_check_feature(dev, DRIVER_MODESET))
> -		return -EINVAL;
> -
> -	/*
> -	 * First, find the plane, crtc, and fb objects.  If not available,
> -	 * we don't bother to call the driver.
> -	 */
> -	plane = drm_plane_find(dev, plane_req->plane_id);
> -	if (!plane) {
> -		DRM_DEBUG_KMS("Unknown plane ID %d\n",
> -			      plane_req->plane_id);
> -		return -ENOENT;
> -	}
> -
>  	/* No fb means shut it down */
> -	if (!plane_req->fb_id) {
> +	if (!fb) {
>  		drm_modeset_lock_all(dev);
>  		old_fb = plane->fb;
>  		ret = plane->funcs->disable_plane(plane);
> @@ -2174,14 +2161,6 @@ int drm_mode_setplane(struct drm_device *dev, void *data,
>  		goto out;
>  	}
>  
> -	crtc = drm_crtc_find(dev, plane_req->crtc_id);
> -	if (!crtc) {
> -		DRM_DEBUG_KMS("Unknown crtc ID %d\n",
> -			      plane_req->crtc_id);
> -		ret = -ENOENT;
> -		goto out;
> -	}
> -
>  	/* Check whether this plane is usable on this CRTC */
>  	if (!(plane->possible_crtcs & drm_crtc_mask(crtc))) {
>  		DRM_DEBUG_KMS("Invalid crtc for plane\n");
> @@ -2189,14 +2168,6 @@ int drm_mode_setplane(struct drm_device *dev, void *data,
>  		goto out;
>  	}
>  
> -	fb = drm_framebuffer_lookup(dev, plane_req->fb_id);
> -	if (!fb) {
> -		DRM_DEBUG_KMS("Unknown framebuffer ID %d\n",
> -			      plane_req->fb_id);
> -		ret = -ENOENT;
> -		goto out;
> -	}
> -
>  	/* Check whether this plane supports the fb pixel format. */
>  	for (i = 0; i < plane->format_count; i++)
>  		if (fb->pixel_format == plane->format_types[i])
> @@ -2212,43 +2183,25 @@ int drm_mode_setplane(struct drm_device *dev, void *data,
>  	fb_height = fb->height << 16;
>  
>  	/* Make sure source coordinates are inside the fb. */
> -	if (plane_req->src_w > fb_width ||
> -	    plane_req->src_x > fb_width - plane_req->src_w ||
> -	    plane_req->src_h > fb_height ||
> -	    plane_req->src_y > fb_height - plane_req->src_h) {
> +	if (src_w > fb_width ||
> +	    src_x > fb_width - src_w ||
> +	    src_h > fb_height ||
> +	    src_y > fb_height - src_h) {
>  		DRM_DEBUG_KMS("Invalid source coordinates "
>  			      "%u.%06ux%u.%06u+%u.%06u+%u.%06u\n",
> -			      plane_req->src_w >> 16,
> -			      ((plane_req->src_w & 0xffff) * 15625) >> 10,
> -			      plane_req->src_h >> 16,
> -			      ((plane_req->src_h & 0xffff) * 15625) >> 10,
> -			      plane_req->src_x >> 16,
> -			      ((plane_req->src_x & 0xffff) * 15625) >> 10,
> -			      plane_req->src_y >> 16,
> -			      ((plane_req->src_y & 0xffff) * 15625) >> 10);
> +			      src_w >> 16, ((src_w & 0xffff) * 15625) >> 10,
> +			      src_h >> 16, ((src_h & 0xffff) * 15625) >> 10,
> +			      src_x >> 16, ((src_x & 0xffff) * 15625) >> 10,
> +			      src_y >> 16, ((src_y & 0xffff) * 15625) >> 10);
>  		ret = -ENOSPC;
>  		goto out;
>  	}
>  
> -	/* Give drivers some help against integer overflows */
> -	if (plane_req->crtc_w > INT_MAX ||
> -	    plane_req->crtc_x > INT_MAX - (int32_t) plane_req->crtc_w ||
> -	    plane_req->crtc_h > INT_MAX ||
> -	    plane_req->crtc_y > INT_MAX - (int32_t) plane_req->crtc_h) {
> -		DRM_DEBUG_KMS("Invalid CRTC coordinates %ux%u+%d+%d\n",
> -			      plane_req->crtc_w, plane_req->crtc_h,
> -			      plane_req->crtc_x, plane_req->crtc_y);
> -		ret = -ERANGE;
> -		goto out;
> -	}
> -
>  	drm_modeset_lock_all(dev);
>  	old_fb = plane->fb;
>  	ret = plane->funcs->update_plane(plane, crtc, fb,
> -					 plane_req->crtc_x, plane_req->crtc_y,
> -					 plane_req->crtc_w, plane_req->crtc_h,
> -					 plane_req->src_x, plane_req->src_y,
> -					 plane_req->src_w, plane_req->src_h);
> +					 crtc_x, crtc_y, crtc_w, crtc_h,
> +					 src_x, src_y, src_w, src_h);
>  	if (!ret) {
>  		plane->crtc = crtc;
>  		plane->fb = fb;
> @@ -2265,6 +2218,81 @@ out:
>  		drm_framebuffer_unreference(old_fb);
>  
>  	return ret;
> +
> +}
> +
> +/**
> + * drm_mode_setplane - configure a plane's configuration
> + * @dev: DRM device
> + * @data: ioctl data*
> + * @file_priv: DRM file info
> + *
> + * Set plane configuration, including placement, fb, scaling, and other factors.
> + * Or pass a NULL fb to disable (planes may be disabled without providing a
> + * valid crtc).
> + *
> + * Returns:
> + * Zero on success, errno on failure.
> + */
> +int drm_mode_setplane(struct drm_device *dev, void *data,
> +		      struct drm_file *file_priv)
> +{
> +	struct drm_mode_set_plane *plane_req = data;
> +	struct drm_mode_object *obj;
> +	struct drm_plane *plane;
> +	struct drm_crtc *crtc = NULL;
> +	struct drm_framebuffer *fb = NULL;
> +
> +	if (!drm_core_check_feature(dev, DRIVER_MODESET))
> +		return -EINVAL;
> +
> +	/* Give drivers some help against integer overflows */
> +	if (plane_req->crtc_w > INT_MAX ||
> +	    plane_req->crtc_x > INT_MAX - (int32_t) plane_req->crtc_w ||
> +	    plane_req->crtc_h > INT_MAX ||
> +	    plane_req->crtc_y > INT_MAX - (int32_t) plane_req->crtc_h) {
> +		DRM_DEBUG_KMS("Invalid CRTC coordinates %ux%u+%d+%d\n",
> +			      plane_req->crtc_w, plane_req->crtc_h,
> +			      plane_req->crtc_x, plane_req->crtc_y);
> +		return -ERANGE;
> +	}
> +
> +	/*
> +	 * First, find the plane, crtc, and fb objects.  If not available,
> +	 * we don't bother to call the driver.
> +	 */
> +	obj = drm_mode_object_find(dev, plane_req->plane_id,
> +				   DRM_MODE_OBJECT_PLANE);
> +	if (!obj) {
> +		DRM_DEBUG_KMS("Unknown plane ID %d\n",
> +			      plane_req->plane_id);
> +		return -ENOENT;
> +	}
> +	plane = obj_to_plane(obj);
> +
> +	if (plane_req->fb_id) {
> +		fb = drm_framebuffer_lookup(dev, plane_req->fb_id);
> +		if (!fb) {
> +			DRM_DEBUG_KMS("Unknown framebuffer ID %d\n",
> +				      plane_req->fb_id);
> +			return -ENOENT;
> +		}
> +
> +		obj = drm_mode_object_find(dev, plane_req->crtc_id,
> +					   DRM_MODE_OBJECT_CRTC);
> +		if (!obj) {
> +			DRM_DEBUG_KMS("Unknown crtc ID %d\n",
> +				      plane_req->crtc_id);
> +			return -ENOENT;
> +		}
> +		crtc = obj_to_crtc(obj);
> +	}
> +
> +	return setplane_internal(crtc, plane, fb,
> +				 plane_req->crtc_x, plane_req->crtc_y,
> +				 plane_req->crtc_w, plane_req->crtc_h,
> +				 plane_req->src_x, plane_req->src_y,
> +				 plane_req->src_w, plane_req->src_h);
>  }
>  
>  /**



Reviewed-by: Pallavi G <pallavi.g@intel.com>