Re: [Qemu-devel] [PATCH 06/18] nbd/client: refactor drop_sync

[Paolo Bonzini]

On 08/02/2017 08:55, Vladimir Sementsov-Ogievskiy wrote:
> 07.02.2017 02:19, Eric Blake wrote:
>> On 02/03/2017 09:47 AM, Vladimir Sementsov-Ogievskiy wrote:
>>> Return 0 on success to simplify success checking.
>>>
>>> Signed-off-by: Vladimir Sementsov-Ogievskiy <address@hidden>
>>> ---
>>>  nbd/client.c | 35 +++++++++++++++++++----------------
>>>  1 file changed, 19 insertions(+), 16 deletions(-)
>> I'm not sure that this simplifies anything.  You have a net addition in
>> lines of code, so unless some later patch is improved because of this,
>> I'm inclined to say this is needless churn.
>>
> 
> I just dislike duplicating information like "drop_sync(ioc, 124) !=
> 124". In the code there is no place where positive and not equal to size
> return value actually handled. But it is not so important, if you are
> against i'll drop this, no problem.

I think I agree with Vladimir.

> One note: I don't have good understanding of the following: actually
> read can return positive value < queried size, which means that we
> should read again. But it is not handled in the code (handled, but just
> as an error), except drop_sync.. (With drop_sync it is side effect of
> using limited buffer size, yes?). Is it all ok?

It is handled in nbd_wr_syncv.

Paolo