SDF_FREEZE_INITIATOR
set_bit(SDF_FREEZE_INITIATOR, &sdp->sd_flags);
if (!test_bit(SDF_FREEZE_INITIATOR, &sdp->sd_flags)) {
clear_bit(SDF_FREEZE_INITIATOR, &sdp->sd_flags);
test_bit(SDF_FREEZE_INITIATOR, &f),