B_NOCACHE
if (!ISSET(bp->b_flags, B_NOCACHE)) {
CLR(bp->b_flags, B_NOCACHE); /* Must cache delayed writes */
if (ISSET(bp->b_flags, (B_NOCACHE|B_ERROR)))
CLR(bp->b_flags, (B_AGE | B_ASYNC | B_NOCACHE | B_DEFERRED));
bp->b_flags |= B_NOCACHE;
if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE)) == B_ASYNC)
(B_BUSY|B_DELWRI|B_NEEDCOMMIT|B_NOCACHE))!=B_DELWRI)
bp->b_flags |= B_NOCACHE;
bp->b_flags |= B_NOCACHE;
bp->b_flags |= B_NOCACHE;
bp->b_flags = B_BUSY | B_NOCACHE | B_RAW | (flags & (B_READ|B_ASYNC));