Replace kmalloc+memset with kcalloc and simplify
Signed-off-by: NYan Burman <burman.yan@gmail.com>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>