Il 11/03/2013 11:19, Peter Lieven ha scritto:
>
> Am 11.03.2013 um 11:16 schrieb Paolo Bonzini <pbonz...@redhat.com>:
>
>> Il 11/03/2013 11:05, Peter Lieven ha scritto:
>>> ensure that there are no pending I/Os before calling
>>> the sync readcapacity commands. the block_resize monitor
>>> command will also flush all I/O, but double check in
>>> case iscsi_truncate() is called from elsewhere in the
>>> future.
>>>
>>> Signed-off-by: Peter Lieven <p...@kamp.de>
>>> ---
>>> block/iscsi.c | 4 ++++
>>> 1 file changed, 4 insertions(+)
>>>
>>> diff --git a/block/iscsi.c b/block/iscsi.c
>>> index 3d52921..de20d53 100644
>>> --- a/block/iscsi.c
>>> +++ b/block/iscsi.c
>>> @@ -1167,6 +1167,10 @@ static int iscsi_truncate(BlockDriverState *bs,
>>> int64_t offset)
>>> return -ENOTSUP;
>>> }
>>>
>>> + /* ensure all async requests are completed before executing
>>> + * a sync readcapacity */
>>> + bdrv_drain_all();
>>> +
>>> if ((ret = iscsi_readcapacity_sync(iscsilun)) != 0) {
>>> return ret;
>>> }
>>
>> NACK to this patch. It would be a bug, let's fix it properly.
>
> ok, are you sure that never ever will some new feature call bdrv_truncate()
> on an iscsi
> device?
I'm sure some new feature _will_ call bdrv_truncate(). But as things
stand now, it would be a bug to do so on an iSCSI device.
For example, qcow1 (and VHDX) will already call it, but that's a bug and
should be fixed otherwise. Your patch will just cause an assertion failure.
Paolo
> otherwise the real fix would be to implement async read capacity commands
> like it
> the first patch version for iscsi_truncate().
>
> Peter
>
>
>>
>> The other two are fine, however.
>>
>> Paolo
>
