NixOS 20.03 is built on kernel 5.4 and 19.09 is on 4.19, so we should update
this option to the highest value possible, per linked upstream instructions from
Amazon.
Since 34234dcb51, for resize2fs to be automatically included in
initrd, a filesystem needed for boot must be explicitly defined as an
ext* type filesystem.
- Add a new parameter `imageType` that can specify either "efi" or
"legacy" (the default which should see no change in behaviour by
this patch).
- EFI images get a GPT partition table (instead of msdos) with a
mandatory ESP partition (so we add an assert that `partitioned`
is true).
- Use the partx tool from util-linux to determine exact start + size
of the root partition. This is required because GPT stores a secondary
partition table at the end of the disk, so we can't just have
mkfs.ext4 create the filesystem until the end of the disk.
- (Unrelated to any EFI changes) Since we're depending on the
`-E offset=X` option to mkfs which is only supported by e2fsprogs,
disallow any attempts of creating partitioned disk images where
the root filesystem is not ext4.
This changes much of the make-disk-image.nix logic (and thus most NixOS
image building) to use LKL to set up the target directory structure rather
than a Linux VM. The only work we still do in a VM is less IO-heavy stuff
that while still time-consuming, is less of the overall load. The goal is
to kill more of that stuff, but that will require deeper changes to NixOS
activation scripts and switch-to-configuration.pl, and I don't want to
bite off too much at once.
This makes make-disk-image.nix slightly more consistent with other image
builders we have. Unfortunately I duplicated some code in doing so, but
this is temporary duplication on the path to consolidating everything.
See https://github.com/NixOS/nixpkgs/issues/23052 for more details on that.
I'm also exposing the option in the amazon-image.nix maintainer module.
We now generate a qcow2 image to prevent hitting Hydra's output size
limit. Also updated /root/user-data -> /etc/ec2-metadata/user-data.
http://hydra.nixos.org/build/33843133
The EBS and S3 (instance-store) AMIs are now created from the same
image. HVM instance-store AMIs are also generated.
Disk image generation has been factored out into a function
(nixos/lib/make-disk-image.nix) that can be used to build other kinds
of images.
