bread
bread(daddr_t blkno, char *buf, int size)
bread(int fd, char *buf, ufs_daddr_t blk, long size)
bread(daddr_t bno, char *buf, long cnt)
bread(daddr_t bno, char *buf, int cnt)
bread(struct vnode *vp, off_t loffset, int size, struct buf **bpp)