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/ (local) 
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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