Re: [PATCH v2] ata: libata-sata: Use LBA from sense data descriptor

[Damien Le Moal <dlemoal@kernel.org>]

On 4/10/25 23:04, Niklas Cassel wrote:
> On Thu, Apr 10, 2025 at 03:02:33PM +0200, Niklas Cassel wrote:
>>
>> I guess now when we do have access to the information, the most consistent
>> thing would be to fill all field we can in qc->result_tf... but, to do this
>> for every IO might slow things down.
>>
>> So is there perhaps some logic to only filling LBA (in addition to STATUS
>> and ERROR, which are filled for all NCQ commands), since that is the only
>> field that can change, as per the specs.
> 
> Looking at this more closely:
> https://github.com/torvalds/linux/blob/v6.15-rc1/include/linux/libata.h#L574-L577
> 
> FEATURE is a union with ERROR, so we cannot save it in qc->result_tf.
> 
> COMMAND is a union with STATUS, so we cannot save it in qc->result_tf.
> 
> 
> The sense data descriptor does not provide AUXILIARY, nor DEVICE,
> so we cannot save these.
> 
> 
> I will send a v3 that does populate COUNT (7:0) and COUNT (15:8),
> since it is only so few fields that we do have, we might as well
> populate them properly.

+1

> 
> 
> Kind regards,
> Niklas


-- 
Damien Le Moal
Western Digital Research