Development install manual: no /opt under NixOS FHS?

evilmav

I'm trying to reproduce the Vivado installation as is described under beta manual. It says I'm supposed to install Vivado from under FHS chroot for NixOS, so what I do is:

$ nix develop git+https://github.com/m-labs/artiq.git  
$ vivado-env
<go to unpacked vivado dir>
$  ./xsetup --agree XilinxEULA,3rdPartyEULA -b Install -e 'Vitis Unified Software Platform' -l /opt/Xilinx/

It still asks me to select a product from the list - I choose Vitis and end up in "ERROR: There is not enough disk space on /opt/Xilinx/ to install.".

I have no experience in working with FHS, but this seems odd to me:
$ df -h Filesystem Size Used Avail Use% Mounted on /dev/sda3 456G 48G 407G 11% /host devtmpfs 388M 0 388M 0% /dev tmpfs 3,8G 0 3,8G 0% /dev/shm tmpfs 1,9G 7,0M 1,9G 1% /run tmpfs 3,8G 576K 3,8G 1% /run/wrappers tmpfs 776M 12K 776M 1% /run/user/175 tmpfs 776M 12K 776M 1% /run/user/1000 /dev/sda1 799M 53M 746M 7% /boot none 3,8G 0 3,8G 0% / /dev/sda3 456G 48G 407G 11% /srv
- there would be indeed no way to add anything to / and /opt itself actually does not exist. If I create it manually, it is gone next time I exit and reenter the FHS env. So where is it supposed to come from? I've tried adding nix.sandboxPaths = ["/opt"]; to the configuration, though the flake.nix has the extra-sandbox-paths option included anyway. I can't find any documentation on what else I'm supposed to do, so could you elaborate please?

Running NixOS on the unstable channel, nix is 2.8 with flakes enabled.

sb10q

mkdir /opt as root on the system before proceeding (before entering the FHS environment).

evilmav

Ok, I did. So now it said it could not write to /opt under FSH einvironment due to permissions. sudo can't be used in the environment. I've tried running sudo vivado-env instead - then it works, but Xilinx folder is created in the actual /opt directory outside the environment as if I was doing it without it at all. Which kind of defeats the whole purpose of this alltogether, doesn't it? I do not think I understand how the environment is supposed to work..

sb10q

Vivado is not designed to be packaged with Nix; there are some derivations floating around but they are quite clumsy to use for a number of reasons (private Xilinx download links, very large files being copied around, ...)
So we have a simpler solution where Vivado is installed as Xilinx intended under the real /opt and not in the Nix store, and use buildFHSUserEnv so that the unpatched Vivado binaries run properly (including on NixOS).
Nix is used normally for all the other (open source) software in ARTIQ.

sb10q

Regarding the sudo problem: I never run any Xilinx software as root so I'm not aware of it. You can install Vivado into your home folder and move it to /opt later (adjusting the settings*.sh files), or give your user write permissions to /opt/Xilinx.

evilmav

OK, seems like I was under completely wrong impression of what buildFHSUserEnv is supposed to do from nixpkgs manual - I was thinking it is chrooting into some /nix/store location and expected anything I do to land somewhere under <chroot>/opt. Now it makes sense, thank you for clearing this up!