BTRFS_FEATURE_COMPAT_RO_SUPP
~BTRFS_FEATURE_COMPAT_RO_SUPP))
const u64 compat_ro_unsupp = (compat_ro & ~BTRFS_FEATURE_COMPAT_RO_SUPP);
[FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,