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struct drm_rect represents a simple rectangle. The utility functions are there to help driver writers. v2: Moved the region stuff into its own file, made the smaller funcs static inline, used 64bit maths in the scaled clipping function to avoid overflows (instead it will saturate to INT_MIN or INT_MAX). v3: Renamed drm_region to drm_rect, drm_region_clip to drm_rect_intersect, and drm_region_subsample to drm_rect_downscale. v4: Renamed some function parameters, improve kernel-doc comments a bit, and actually generate documentation for drm_rect.[ch]. v5: s/RETUTRNS/RETURNS/ Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Acked-by: Dave Airlie <airlied@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
************************************************************ * For the very latest on DRI development, please see: * * http://dri.freedesktop.org/ * ************************************************************ The Direct Rendering Manager (drm) is a device-independent kernel-level device driver that provides support for the XFree86 Direct Rendering Infrastructure (DRI). The DRM supports the Direct Rendering Infrastructure (DRI) in four major ways: 1. The DRM provides synchronized access to the graphics hardware via the use of an optimized two-tiered lock. 2. The DRM enforces the DRI security policy for access to the graphics hardware by only allowing authenticated X11 clients access to restricted regions of memory. 3. The DRM provides a generic DMA engine, complete with multiple queues and the ability to detect the need for an OpenGL context switch. 4. The DRM is extensible via the use of small device-specific modules that rely extensively on the API exported by the DRM module. Documentation on the DRI is available from: http://dri.freedesktop.org/wiki/Documentation http://sourceforge.net/project/showfiles.php?group_id=387 http://dri.sourceforge.net/doc/ For specific information about kernel-level support, see: The Direct Rendering Manager, Kernel Support for the Direct Rendering Infrastructure http://dri.sourceforge.net/doc/drm_low_level.html Hardware Locking for the Direct Rendering Infrastructure http://dri.sourceforge.net/doc/hardware_locking_low_level.html A Security Analysis of the Direct Rendering Infrastructure http://dri.sourceforge.net/doc/security_low_level.html