[dm-devel] [PATCH 03/11] libata: Send internal commands through the block layer

[John Garry]

On 22/03/2022 11:20, Christoph Hellwig wrote:
> On Tue, Mar 22, 2022 at 06:39:37PM +0800, John Garry wrote:
>> When SCSI HBA device drivers are required to process an ATA internal
>> command they still need a tag for the IO. This often requires the driver
>> to set aside a set of tags for these sorts of IOs and manage the tags
>> themselves.
>>
>> If we associate a SCSI command (and request) with an ATA internal command
>> then the tag is already provided, so introduce the change to send ATA
>> internal commands through the block layer with a set of custom blk-mq ops.
>>
>> note: I think that the timeout handling needs to be fixed up.
> 
> Any reason to not just send them through an ATA_16 passthrough CDB and
> just use all the normal SCSI command handling?
> 
> .

No reason that I know about.

TBH, I was hoping that someone woud have a better idea on how to do this 
as what I was doing was messy.

Let me check it.

Cheers,
John