glfs_zerofill() can be potentially called to zero-out entire file and hence allow for bigger value of length parameter. Change-Id: I75f1d11af298915049a3f3a7cb3890a2d72fca63 BUG: 1028673 Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Reviewed-on: http://review.gluster.org/6266 Tested-by: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: M. Mohan Kumar <mohan@in.ibm.com> Tested-by: M. Mohan Kumar <mohan@in.ibm.com> Reviewed-by: Anand Avati <avati@redhat.com>