so any extent which ended right at 4G was stopping the extent
walk. Just replacing these values with the extent block &
length should fix it.
Also give blksize_bits a saner type, and reverse the order
of the tests to make the more likely case tested first.
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reported-by: Carl Henrik Lunde <chlunde@ping.uio.no> Tested-by: Carl Henrik Lunde <chlunde@ping.uio.no> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>