rbd: define rbd_snap_size() and rbd_snap_features()
This patch defines a handful of new functions that will allow
us to get rid of the rbd device structure's list of snapshots.
Define rbd_snap_id_by_name() to look up a snapshot id given its
name. This is efficient for format 1 images but not for format 2.
Fortunately it only gets called at mapping time so it's not that
critical.
Use rbd_snap_id_by_name() to find out the id for a snapshot getting
mapped, and pass that id to new functions rbd_snap_size() and
rbd_snap_features() to look up information about a given snapshot's
size and feature mask given its snapshot id. All this gets done
in rbd_dev_mapping_set().
As a result, snap_by_name() is no longer needed, so get rid of it.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
1 file changed