Merge branch 'stable/xen-swiotlb.bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb-2.6

* 'stable/xen-swiotlb.bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb-2.6:
  swiotlb: Export swioltb_nr_tbl and utilize it as appropiate.