SysV IPC shared memory and virtual alising

[Atsushi Nemoto <nemoto@toshiba-tops.co.jp>]

Here is an patch to fix virtual aliasing problem with SysV IPC shared
memory.  I tested this patch on a r4k cpu with 32Kb D-cache.

If D-cache is smaller than PAGE_SIZE this patch is not needed at all,
but I think it is not so bad unconditionally forcing alignment to
SHMLBA.

---
Atsushi Nemoto

unmapped_area.patch
Description: Text document