Calculating the base address of the segment is tricky and is used in
several places as well.  This patch moves this tricky part in a common
place as suggested by Andi Kleen.
Signed-of-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>