Re: Enabling peer to peer device transactions for PCIe devices

Dan Williams
2016-12-06T22:02:19Z

On Tue, Dec 6, 2016 at 1:47 PM, Logan Gunthorpe <logang-OTvnGxWRz7hWk0Htik3J/w@public.gmane.org> wrote:
> Hey,
>
>> Okay, so clearly this needs a kernel side NVMe specific allocator
>> and locking so users don't step on each other..
>
> Yup, ideally. That's why device dax isn't ideal for this application: it
> doesn't provide any way to prevent users from stepping on each other.

On this particular point I'm in the process of posting patches that
allow device-dax sub-division, so you could carve up a bar into
multiple devices of various sizes.