On 9/11/25 4:03 PM, Damien Le Moal wrote:
I suspect it is because this will be handled by the flush machinery during the
submit_bio() to the underlying device ?
Indeed.
But if that is the case, why is it a problem with multiple devices ?
The same block layer flush machinery will handle that preflush write for all devices.
The REQ_PREFLUSH semantics require that the REQ_PREFLUSH is submitted to
*all* underlying devices before the data that is included in the bio is
written, even if the data in the bio only affects a single underlying
device.
Thanks,
Bart.
