Re: [PATCH v12 13/13] dm: add power-of-2 target for zoned devices with non power-of-2 zone sizes

From: Shinichiro Kawasaki
Date: Mon Aug 29 2022 - 22:52:46 EST


On Aug 23, 2022 / 14:18, Pankaj Raghav wrote:
> Only zoned devices with power-of-2(po2) number of sectors per zone(zone
> size) were supported in linux but now non power-of-2(npo2) zone sizes
> support has been added to the block layer.
>
> Filesystems such as F2FS and btrfs have support for zoned devices with
> po2 zone size assumption. Before adding native support for npo2 zone
> sizes, it was suggested to create a dm target for npo2 zone size device to
> appear as a po2 zone size target so that file systems can initially
> work without any explicit changes by using this target.

FYI, with this patch series, I created the new dm target and ran blktests zbd
group for it. And I observed zbd/007 test case failure (other test cases
passed). The test checks sector mapping of zoned dm-linear, dm-flakey and dm-
crypt. Some changes in the test case look required to handle the new target.

--
Shin'ichiro Kawasaki