phys(2) under sVr3?

[Scott E. Preece]

  From: Andrew Klossner <andrew at frip.gwd.tek.com>
> I need to augment sys V release 3 so as to let a user process map a
> video frame buffer into its address space.  Something like the version 7
> phys(2) call, or what the 4.2BSD mmap(2) call promised but didn't
> deliver, is what I'm looking for.
----------
In release 2.1 of Gould's UTX/32 (4.3 + System V emulation) we have
added the ability to configure a system with specific areas of physical
memory defined as special, so that the kernel will not allocate them for
general use  We call those areas extents.  It is then possible, either
in the system configuration file or by using a new system call, to
create regions at specified offsets from the beginning of specified
extents.  When a region is created, a System V shared memory object is
created as its handle.  Jobs may then attach to that object to get
access to the appropriate area of physical memory.

We have also provided a way for jobs to request attachment to specified
shared memory objects at exec time, using information stuffed into the
COFF (well, COFF-like) header.

Finally, we also added a second class of region for which "attachment"
means allocating pages from the pool covered by the region.  This allows
handling areas of memory that have special characteristics (Gould
systems can have cache-speed memory boards mixed with regular memory)
but don't need contiguous allocation.

-- 
scott preece
gould/csd - urbana
uucp:	ihnp4!uiucuxc!urbsdc!preece
arpa:	preece at Gould.com