From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
Subject: Re: Enabling peer to peer device transactions for PCIe devices
Date: Tue, 6 Dec 2016 09:38:50 -0700
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> > I'm not opposed to mapping /dev/nvmeX.  However, the lookup is trivial
> > to accomplish in sysfs through /sys/dev/char to find the sysfs path of the
> > device-dax instance under the nvme device, or if you already have the nvme
> > sysfs path the dax instance(s) will appear under the "dax" sub-directory.
> 
> Personally I think mapping the dax resource in the sysfs tree is a nice
> way to do this and a bit more intuitive than mapping a /dev/nvmeX.

It is still not at all clear to me what userpsace is supposed to do
with this on nvme.. How is the CMB usable from userspace?

Jason