tree 2c4e649eaa7ea7a73fa29d603c019d7df7fa287a
parent 7ef3214af220515b8fe223ec92ec017d2e5607a7
author Alex Elder <elder@dreamhost.com> 1328637816 -0600
committer Alex Elder <elder@dreamhost.com> 1332431270 -0500

rbd: fix module sysfs setup/teardown code

Once rbd_bus_type is registered, it allows an "add" operation via
the /sys/bus/rbd/add bus attribute, and adding a new rbd device that
way establishes a connection between the device and rbd_root_dev.
But rbd_root_dev is not registered until after the rbd_bus_type
registration is complete.  This could (in principle anyway) result
in an invalid state.

Since rbd_root_dev has no tie to rbd_bus_type we can reorder these
two initializations and never be faced with this scenario.

In addition, unregister the device in the event the bus registration
fails at module init time.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>