[PATCH] nvme: enable retries for authentication commands

[Hannes Reinecke]

On 1/25/24 17:50, Jens Axboe wrote:
> On 1/25/24 9:20 AM, Hannes Reinecke wrote:
>> On 1/25/24 16:48, Christoph Hellwig wrote:
>>> On Thu, Jan 25, 2024 at 08:42:10AM -0700, Jens Axboe wrote:
>>>> On 1/25/24 6:09 AM, hare at kernel.org wrote:
>>>>> From: Hannes Reinecke <hare at suse.de>
>>>>>
>>>>> Authentication commands are normal NVMe commands, and as such
>>>>> can return a status where NVME_SC_DNR is not set, indicating
>>>>> that the command should be retried.
>>>>> Rather than checking NVME_SC_DNR manually for each command completion
>>>>> this patch adds a flag 'retry' to __nvme_submit_sync_cmd(), causing
>>>>> the REQ_FAILFAST_DRIVER option to be cleared and the command to
>>>>> be retried via the normal mechanism.
>>>>
>>>> Can we please do this without adding Yet Another parameter to that
>>>> function?
>>>
>>> Heh, I wrote about the same reply a few minutes ago.  I'll try to think
>>> what we can do instead.
>>
>> We could do something like this:
> 
> That won't really do much, and yeah wouldn't be the way even if
> complete. How about just not setting the flag in the first place?
> nvme_init_request() defaults to doing it, so either pass in the init
> flags to that, or just clear it in there and have the callers decide if
> they want to set it.
> 
But that's the thing; the request is never visible to the caller.
So moving things out of the nvme_init_request() doesn't really help.

And open-coding __nvme_submit_sync_cmd() also doesn't look very
appealing.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare at suse.de                              +49 911 74053 688
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