The big hitter here was the bstat field, which contains
different sized time_t on 32 vs. 64 bit.  Add a copyin
function to translate the 32-bit arg to 64-bit, and
call the swapext ioctl helper.
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>