MNT_RECURSE
if ((flags & (MNT_DEFERRED | MNT_RECURSE)) != 0)
(flags & (MNT_RECURSE | MNT_FORCE)) == (MNT_RECURSE | MNT_FORCE),
flags |= MNT_RECURSE;
if ((flags & MNT_RECURSE) != 0) {
MNT_RECURSE | MNT_DEFERRED)
MNT_FORCE | MNT_RECURSE | MNT_DEFERRED, curthread);