On Thu, Jan 16, 2020 at 11:09:00AM -0800, Dan Williams wrote:
> > True, but if kpartx + udev can make this transparent then I
> > think users lose any functionality. They just gain a device-mapper
> > dependency.
> So udev rules will trigger when a /dev/pmemX device shows up and run
> kpartx which in turn will create dm-linear devices and device nodes
> will show up in /dev/mapper/pmemXpY.
> IOW, /dev/pmemXpY device nodes will be gone. So if any of the scripts or
> systemd unit files are depenent on /dev/pmemXpY, these will still be
> broken out of the box and will have to be modified to use device nodes
> in /dev/mapper/ directory instead. Do I understand it right, Or I missed
> the idea completely.
No, I'd write the udev rule to create links from /dev/pmemXpY to the
/dev/mapper device, and that rule would be gated by a new pmem device
attribute to trigger when kpartx needs to run vs the kernel native
Got it. This sounds much better.