S_BLKSIZE
sb->st_blocks = vap->va_bytes / S_BLKSIZE;
sbp->f_bsize = S_BLKSIZE;
sbp->f_bsize = S_BLKSIZE;
vap->va_size = S_BLKSIZE;
vap->va_blocksize = S_BLKSIZE;
vap->va_bytes = S_BLKSIZE;
sb->st_blocks = vap->va_bytes / S_BLKSIZE;
vap->va_bytes = fat->blocks * S_BLKSIZE;