the 2D driver initializes MC_FB_LOCATION and related registers sanely
the DRM deduces the layout from these registers
clients use the new SETPARAM ioctl to tell the DRM where they think the
framebuffer is located in the card's address space
the DRM uses all this information to check client state and fix it up if
necessary
This is a prerequisite for things like direct rendering with IGP chips and
video capturing.
get the drm_file_t * based on the filp passed in ioctl handlers.
- Use this macro on BSD for simplification and improve its error reporting.
Make failure to find the drm_file_t * print as an error, not debug.
This failure may be part of the problem with KDE.
- Make debug and error print macros include the pid on BSD.
DRM_*MEMORYBARRIER we had were related to an MMIO space. This means
arch-specific code on the BSDs, unfortunately. Also add
DRM_MEMORYBARRIER() and change the DRM_READMEMORYBARRIER()s that used
to be read/write barriers to it.