BH_Dirty
(1 << BH_Dirty) | (1 << BH_Uptodate));
(bh->b_state & ((1 << BH_Dirty) | (1 << BH_Lock)));
BIT(BH_Dirty)|BIT(BH_Uptodate));
const unsigned long b_state = (1UL << BH_Dirty)|(1UL << BH_Pinned)|(1UL << BH_Lock);
((bh)->b_state & ((1ul << BH_Dirty) | (1ul << BH_Lock) | (1ul << BH_Pinned)))
mask |= BIT(BH_Dirty);
(BIT(BH_Uptodate) | BIT(BH_Dirty) | BIT(BH_Mapped) |
(BIT(BH_Uptodate) | BIT(BH_Dirty) | BIT(BH_Mapped) |
(BIT(BH_Dirty) | BIT(BH_Async_Write) |