tree a5dd9b68bb868f62229f159fd64f3c4322b21edc
parent 4e217b5dc87042b0fa52b11f491c4ded1863823a
author Guangliang Zhao <guangliang@unitedstack.com> 1379993136 +0800
committer Josh Durgin <josh.durgin@inktank.com> 1402448964 -0700

rbd: add ioctl for rbd

When running the following commands:
    [root@ceph0 mnt]# blockdev --setro /dev/rbd1
    [root@ceph0 mnt]# blockdev --getro /dev/rbd1
    0

The block setro didn't take effect, it is because
the rbd doesn't support ioctl of block driver.

This resolves:
	http://tracker.ceph.com/issues/6265

Signed-off-by: Guangliang Zhao <guangliang@unitedstack.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>