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:
- The DRM provides synchronized access to the graphics hardware via the use of an optimized two-tiered lock.
- 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.
- The DRM provides a generic DMA engine, complete with multiple queues and the ability to detect the need for an OpenGL context switch.
- The DRM is extensible via the use of small device-specific modules that rely extensively on the API exported by the DRM module.