Pull vfs fixes from Al Viro:
- backport-friendly part of lock_parent() race fix
- a fix for an assumption in the heurisic used by path_connected() that
is not true on NFS
- livelock fixes for d_alloc_parallel()
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: Teach path_connected to handle nfs filesystems with multiple roots.
fs: dcache: Use READ_ONCE when accessing i_dir_seq
fs: dcache: Avoid livelock between d_alloc_parallel and __d_add
lock_parent() needs to recheck if dentry got __dentry_kill'ed under it