if (mf_write (cf->block_mf, block, offset, nbytes, buf))
{
logf (LOG_FATAL|LOG_ERRNO, "cf_write no=%d, block=%d", no, block);
if (mf_write (cf->block_mf, block, offset, nbytes, buf))
{
logf (LOG_FATAL|LOG_ERRNO, "cf_write no=%d, block=%d", no, block);