tree a48d938dc87ab82353945528d368d2d700da339e
parent fa40e65622352012dccd435147f28161375a6815
author Jeff Cody <jcody@redhat.com> 1403725209 -0400
committer Stefan Hajnoczi <stefanha@redhat.com> 1404204421 +0200

block: add helper function to determine if a BDS is in a chain

This is a small helper function, to determine if 'base' is in the
chain of BlockDriverState 'top'.  It returns true if it is in the chain,
and false otherwise.

If either argument is NULL, it will also return false.

Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>