Re: dm-integrity: estimate the size needed for separate integrity device

[Thorsten Glaser <tg@evolvis.org>]

Hi Ma,

>But I'm not sure what size each "integrity tags" partition should be,
>depending on the data device.

I’ve wondered the same.

I extracted some code from the Linux 5.10 kernel (as that’s what I’m
using on bullseye) to estimate that, once for an already created
split-setup device (if you create it too large and want to shrink)
and once before creating.

It assumes defaults for most parameters, but it does support tag size
and sectors per block. Use at your own risk.

https://codeberg.org/mirabilos/useful-scripts/src/branch/master/integritysetup

Thankfully, the kernel refuses to set up the device if the partition
is too small, so you can test.

Here’s to hoping newer kernels/cryptsetup versions don’t break it ;)

bye,
//mirabilos
-- 
FWIW, I'm quite impressed with mksh interactively. I thought it was much
*much* more bare bones. But it turns out it beats the living hell out of
ksh93 in that respect. I'd even consider it for my daily use if I hadn't
wasted half my life on my zsh setup. :-) -- Frank Terbeck in #!/bin/mksh