Jeff Garzik pointed me to his code to see how to remove a disk from
the system _properly_. Well, here it is...
Every place we remove disks we are now testing before calling del_gendisk
or blk_cleanup_queue and then call put_disk.
Signed-off-by: NMike Miller <mike.miller@hp.com>
Signed-off-by: NJens Axboe <axboe@suse.de>