Original behavior:
  bash-4.1$ make -C vm run_tests
  make: Entering directory `/home/dave/git/linux-2.6/tools/testing/selftests/vm'
  /bin/sh ./run_vmtests
  ./run_vmtests: line 24: /proc/sys/vm/nr_hugepages: Permission denied
  Please run this test as root
  make: *** [run_tests] Error 1
  make: Leaving directory `/home/dave/git/linux-2.6/tools/testing/selftests/vm'

After applying the patch:
  bash-4.1$ make -C vm run_tests
  make: Entering directory `/home/dave/git/linux-2.6/tools/testing/selftests/vm'
  ./run_vmtests: line 24: /proc/sys/vm/nr_hugepages: Permission denied
  Please run this test as root
  vmtests: [FAIL]
  make: Leaving directory `/home/dave/git/linux-2.6/tools/testing/selftests/vm'
Signed-off-by: NDave Young <dyoung@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Also remove -Wextra because gcc-4.6 emits lots of irritating
signed/unsigned comparison warnings.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

hugepage-mmap.c, hugepage-shm.c and map_hugetlb.c in Documentation/vm are
simple pass/fail tests, It's better to promote them to
tools/testing/selftests.

Thanks suggestion of Andrew Morton about this.  They all need firstly
setting up proper nr_hugepages and hugepage-mmap need to mount hugetlbfs.
So I add a shell script run_vmtests to do such work which will call the
three test programs and check the return value of them.

Changes to original code including below:
a. add run_vmtests script
b. return error when read_bytes mismatch with writed bytes.
c. coding style fixes: do not use assignment in if condition

[akpm@linux-foundation.org: build the targets before trying to execute them]
[akpm@linux-foundation.org: Documentation/vm/ no longer has a Makefile. Fixes "make clean"]
Signed-off-by: NDave Young <dyoung@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>