bit_spin_lock
bit_spin_lock(bit ^ be_to_le, iv->bitlock);
bit_spin_lock(BH_JournalHead, &bh->b_state);
bit_spin_lock(0, (unsigned long *)b);
bit_spin_lock(0, (unsigned long *)bkt);
bit_spin_lock(0, (unsigned long *)bucket);
bit_spin_lock(FOLIO_MM_IDS_LOCK_BITNUM, &folio->_mm_ids);
bit_spin_lock(3, &d->bits);
bit_spin_lock(3, &d->bits);
bit_spin_lock(SL_locked, &slab->flags.f);