-- | Valid barrier combinations: "n" or any non-null subset of "bfd"
drbdValidBarrierOpt :: FrozenSet (FrozenSet String)
drbdValidBarrierOpt =
  ConstantUtils.mkSet
  [ ConstantUtils.mkSet [drbdBNone]
  , ConstantUtils.mkSet [drbdBDiskBarriers]
  , ConstantUtils.mkSet [drbdBDiskDrain]
  , ConstantUtils.mkSet [drbdBDiskFlush]
  , ConstantUtils.mkSet [drbdBDiskDrain, drbdBDiskFlush]
  , ConstantUtils.mkSet [drbdBDiskBarriers, drbdBDiskDrain]
  , ConstantUtils.mkSet [drbdBDiskBarriers, drbdBDiskFlush]
  , ConstantUtils.mkSet [drbdBDiskBarriers, drbdBDiskFlush, drbdBDiskDrain]
  ]
drbdValidBarrierOpt :: FrozenSet (FrozenSet String)
drbdValidBarrierOpt =
  ConstantUtils.mkSet
  [ ConstantUtils.mkSet [drbdBNone]
  , ConstantUtils.mkSet [drbdBDiskBarriers]
  , ConstantUtils.mkSet [drbdBDiskDrain]
  , ConstantUtils.mkSet [drbdBDiskFlush]
  , ConstantUtils.mkSet [drbdBDiskDrain, drbdBDiskFlush]
  , ConstantUtils.mkSet [drbdBDiskBarriers, drbdBDiskDrain]
  , ConstantUtils.mkSet [drbdBDiskBarriers, drbdBDiskFlush]
  , ConstantUtils.mkSet [drbdBDiskBarriers, drbdBDiskFlush, drbdBDiskDrain]
  ]
drbdValidBarrierOpt =
  ConstantUtils.mkSet
  [ ConstantUtils.mkSet [drbdBNone]
  , ConstantUtils.mkSet [drbdBDiskBarriers]
  , ConstantUtils.mkSet [drbdBDiskDrain]
  , ConstantUtils.mkSet [drbdBDiskFlush]
  , ConstantUtils.mkSet [drbdBDiskDrain, drbdBDiskFlush]
  , ConstantUtils.mkSet [drbdBDiskBarriers, drbdBDiskDrain]
  , ConstantUtils.mkSet [drbdBDiskBarriers, drbdBDiskFlush]
  , ConstantUtils.mkSet [drbdBDiskBarriers, drbdBDiskFlush, drbdBDiskDrain]
  ]