On 16.06.2020 09:07, Keith Busch wrote:
On Tue, Jun 16, 2020 at 05:55:26PM +0200, Javier González wrote:
On 16.06.2020 08:48, Keith Busch wrote:
> On Tue, Jun 16, 2020 at 05:02:17PM +0200, Javier González wrote:
> > This depends very much on how the FS / application is managing
> > stripping. At the moment our main use case is enabling user-space
> > applications submitting I/Os to raw ZNS devices through the kernel.
> >
> > Can we enable this use case to start with?
>
> I think this already provides that. You can set the nsid value to
> whatever you want in the passthrough interface, so a namespace block
> device is not required to issue I/O to a ZNS namespace from user space.
Mmmmm. Problem now is that the check on the nvme driver prevents the ZNS
namespace from being initialized. Am I missing something?
Hm, okay, it may not work for you. We need the driver to create at least
one namespace so that we have tags and request_queue. If you have that,
you can issue IO to any other attached namespace through the passthrough
interface, but we can't assume there is an available namespace.
That makes sense for now.
The next step for us is to enable a passthrough on uring, making sure
that I/Os do not split.
Does this make sense to you?
Thanks,
Javier
