This fixes the mincore syscall in three ways:

 (1) It moves as much argument checking outside of the semaphore-holding
     region as possible.

 (2) It checks the region parameters against TASK_SIZE so that a 32-bit binary
     on a 64-bit platform will get the right error when calling this syscall
     on a region that overlaps the end of the 32-bit address space.

 (3) It tidies up the VMA checking loop a little.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-Off-By: Linus Torvalds <torvalds@osdl.org>