b_xflags_t
b_xflags_t xflags;
b_xflags_t flags;
buf_vlist_find_or_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags)
buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags)
b_xflags_t b_xflags; /* extra flags */