Re: [PATCH 07/18] scsi: revamp host device handling

Hannes Reinecke
2021-05-04T13:10:43Z

On 5/4/21 11:59 AM, Christoph Hellwig wrote:
> So right now scsi_get_host_dev/scsi_free_host_dev is entirely unused.
>
> І'd rather just kill them off rather than giving them a new life and
> hacking all over the core code for them.
>
> What do you need the scsi_device for instead of just having a
> request_queue for comands to the controller? If we need a scsi_device
> can we somehow make sure it doesn't hit the scanning and sysfs code
> from a much higher level?
>
That is what I did in v2, and got the response:

> That was just a question on why virtio uses the per-device tags, which
> didn't look like it made any sense. What I'm worried about here is
> mixing up the concept of reserved tags in the tagset, and queues to
> use them. Note that we already have the scsi_get_host_dev to allocate
> a scsi_device and thus a request_queue for the host itself. That
> seems like the better interface to use a tag for a host wide command
> vs introducing a parallel path.

(To be found at
https://lore.kernel.org/linux-scsi/20200311062228.GA13522@infradead.org/
if you are curious.)

So do you retract on that statement?
Or did I misinterpret something there?

Cheers,

Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
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