B_RAM
if (bp->b_flags & B_RAM) {
if ((bp->b_flags & (B_INVAL | B_CACHE | B_RAM)) ==
bp->b_flags |= B_RAM;
bp->b_flags &= ~B_RAM;
if ((bp->b_flags & B_RAM) == 0)
bp->b_flags &= ~B_RAM;
if ((bp->b_flags & B_RAM) == 0)
bp->b_flags &= ~B_RAM;
if ((bp->b_flags & (B_INVAL | B_CACHE | B_RAM)) == B_CACHE) {