dm-stripe does do_div() on potentially 32bit data.  do_div()
implementation has every right to be Not Happy(tm) with that...

The fix is obvious - that's what sector_div() is for...
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>