mmap/mmap12.c: new case to test MAP_POPULATE of mmap
Create test case for MAP_POPULATE of mmap.
Verify the following statement
"For a file mapping,this causes read-ahead on the file.
Later accesses to the mapping will not be blocked by page faults."
by mmap-ing a file and check if all pages are present.
Signed-off-by: DAN LI <email@example.com>
Reviewed-by: Jan Stancek <firstname.lastname@example.org>
Acked-by: Cyril Hrubis <email@example.com>