Can I/O order be guaranteed by submitting sycn bio

[谢纲]

Hi,

Some journal file systems submits sycn bio to do ordered write  if the
device does not support barrier i/o. But the sync bio only implies the
unplug of the request queue. Some elevators may reorder the request.
It's seems that the bio only with BIO_RW_SYNC flag could not guarantee
the write order. Is this true?

If so, is there any better way to do ordered write when there is no
barrier i/o support.

Thanks,

-- 
Xie Gang
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/