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From:   Benjamin Coddington <bcodding@redhat.com>
To:     Trond Myklebust <trondmy@hammerspace.com>
Cc:     linux-nfs@vger.kernel.org, anna.schumaker@netapp.com
Subject: Re: [PATCH v2 1/5] NFS: Fix error handling for O_DIRECT write
 scheduling
Date:   Wed, 15 Nov 2023 16:30:24 -0500
Message-ID: <C9BC9AC4-DD95-4CC4-AB1F-D38856DB394E@redhat.com>
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On 15 Nov 2023, at 12:16, Trond Myklebust wrote:

> On Wed, 2023-11-15 at 08:04 -0500, Benjamin Coddington wrote:
>> On 9 Nov 2023, at 12:25, Benjamin Coddington wrote:
>>
>>> On 9 Nov 2023, at 11:53, Trond Myklebust wrote:
>>>>
>>>> Hi Ben,
>>>>
>>>> Relying on the value of dreq->bytes_left is just not a good idea,
>>>> given
>>>> that the layoutget request could end up returning NFS4ERR_DELAY.
>>>>
>>>> How about something like the following patch?
>>>
>>> That looks promising!  I think ->bytes_left could get dropped after
>>> this.
>>>
>>> I'll send it through some testing and report back, thanks!
>>
>> This definitely fixes it, sorry for the delay getting back.
>>
>> Fixes: 954998b60caa ("NFS: Fix error handling for O_DIRECT write
>> scheduling")
>> Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
>> Tested-by: Benjamin Coddington <bcodding@redhat.com>
>>
>> It creates some clear additional work to remove nfs_direct_req-
>>> bytes_left
>> (I don't think its needed anymore) and fixup the nfs_direct_req_class
>> tracepoint, which could be a follow-up patch or get folded in.
>>
>
> Thank you! I'll queue that patch up so it gets included in the next
> bugfix pull request.

Thank you for the fix.

> I agree that we should get rid of the bytes_left field. We can queue
> something up for that in the next merge window.

I have it tested already with yours, I'll send it along.

Ben