rem: printf("readv @ %Ld for %d blocks (at %Ld, block_size = %ld)\n", bnum, num, bnum*bsize,bsize);
add: printf("readv @ %Ld for %d blocks (at %Ld, block_size = %d)\n", bnum, num, bnum*bsize, bsize);
context: read_into_ents(int dev, fs_off_t bnum, cache_ent **ents, int num, int bsize){    int    i, ret;    struct iovec *iov;    iov = get_iovec_array();    for(i=0; i < num; i++) {        iov[i].iov_base = ents[i]->data;        iov[i].iov_len  = bsize;    }	if (chatty_io > 2)		printf("readv @ %Ld for %d blocks (at %Ld, block_size = %ld)\n", bnum, num, bnum*bsize,bsize);    ret = readv_pos(dev, bnum*bsize, iov, num);    release_iovec_array(iov);    if (ret != num*bsize) {        printf("read_into_ents: asked to read %d bytes but got %d\n",               num*bsize, ret);        printf("*** iov @ 0x%x (num %d)\n", iov, num);        return EINVAL;    } else        return 0;}