On 11/2/20 7:58 PM, hch@xxxxxx wrote:
On Mon, Nov 02, 2020 at 10:33:55AM -0800, Keith Busch wrote:
I can see this going one of two ways:
a) Set up the existing controller character device with a generic
disk-less request_queue to the IO queues accepting IO commands to
arbitrary NSIDs.
b) Each namespace that can't be supported gets their own character
device.
I'm leaning toward option "a". While it doesn't create handles to unique
namespaces, it has more resilience to potentially future changes. And I
recall the target side had a potential use for that, too.
The problem with a) is that it can't be used to give users or groups
access to just one namespaces, so it causes a real access control
nightmare. The problem with b) is that now applications will break
when we add support for new command sets or features. I think
c) Each namespace gets its own character device, period.
is the only sensible option.
I hardly dare to mention bsg here; but the is pretty similar to what it
set out to do ...
Or yet another interface?
Cheers,
Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
hare@xxxxxxx +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer
