2.6.22 API change
Unused destroy_dirty_buffers arg removed from prototype.
2.6.24 API change
Empty write barriers are now supported and we should use them.
2.6.24 API change
Size argument dropped from bio_endio and bi_end_io, because the
bi_end_io is only called once now when the request is complete.
There is no longer any need for a size argument. This also means
that partial IO's are no longer possibe and the end_io callback
should not check bi->bi_size. Finally, the return type was updated
to void.
2.6.28 API change
open/close_bdev_excl() renamed to open/close_bdev_exclusive().
2.6.29 API change
BIO_RW_SYNC renamed to BIO_RW_SYNCIO.
Brian Behlendorf