[PATCH 0/5] dm: Initial work on a device mapper

[Jan Lübbe]

On Tue, 2025-09-02 at 11:03 +0200, Ahmad Fatoum wrote:
> > Yeah I noticed that, _very_ useful. For Infix, if we end up going with
> > LVM, I suspect we won't be able to send all of that info along with the
> > commandline, and will end up needing to figure that out (again) in an
> > initramfs - but for most cases I think it would work really well!
> 
> Ah, didn't think of LVM. If mix-and-match is no problem for you, then
> doing it in the initramfs is a workable solution of course.

If you are thinking about LVM, you may want to take a look at how Android is
using dm-linear for "dynamic partitions":
https://source.android.com/docs/core/ota/dynamic_partitions/ab_launch
https://source.android.com/docs/core/ota/dynamic_partitions/implement

This is also related to virtual A/B:
https://source.android.com/docs/core/ota/virtual_ab

The components are "snapuserd" and "dm-user" (which was not merged):
https://lpc.events/event/11/contributions/1049/attachments/826/1562/2021%20LPC_%20dm-snapshot%20in%20user%20space.pdf
https://lwn.net/Articles/838986/

I'm not sure what they use at the moment...

Regards,
Jan

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