GitLab

The generation of aufs objects will be updated by the branch
management (add/del branches, by later commit), and aufs will refresh
the objects based upon the generation.
In refreshing dinfos, aufs will find all ancestors of the given dentry
and store the pointers in dynamically allocated memory. I don't think it
beautiful, but I don't have any other idea.
Signed-off-by: J. R. Okajima <hooanon05g@gmail.com>

The structure is very similar to aufs inode info (in previous commit).
Signed-off-by: J. R. Okajima <hooanon05g@gmail.com>