rbd: implement feature checks
authorAlex Elder <elder@inktank.com>
Tue, 9 Oct 2012 20:50:17 +0000 (13:50 -0700)
committerAlex Elder <elder@inktank.com>
Wed, 10 Oct 2012 14:43:51 +0000 (07:43 -0700)
commitd889140c4a1c5edb6a7bd90392b9d878bfaccfb6
tree518217f86e1e0001e51e7c8a821cba2ac32428c6
parent117973fb4c91f3fd913127577e9f71b3aa6cb556
rbd: implement feature checks

Version 2 images have two sets of feature bit fields.  The first
indicates features possibly used by the image.  The second indicates
features that the client *must* support in order to use the image.

When an image (or snapshot) is first examined, we need to make sure
that the local implementation supports the image's required
features.  If not, fail the probe for the image.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
drivers/block/rbd.c