tvl-depot/tvix/default.nix
Connor Brewster 6b7c936bc5 refactor(tvix/store/fuse): Switch from fuser to fuse-backend-rs
This switches the FUSE implementation from fuser to fuse-backend-rs.
fuse-backend-rs is designed to work with both FUSE and virtiofs.
Virtiofs support will make it possible to plug the tvix-store into a
microvm and have `/nix/store` access without having to setup FUSE inside
the guest.

Additionally fuse-backend-rs has nice support for running multiple FUSE
threads and has some async support.

The goal of this commit is to mechanically switch over to
fuse-backend-rs with minimal changes. I did have to add some locks here
and there because fuse-backend-rs uses `&self` on all methods whereas
fuser uses `&mut self`. `&self` is required for concurrent access to the
FUSE server, so this makes sense.

We can consider switching to concurrent maps and use some other
techniques to reduce lock contention and critical section size.

Issue: https://b.tvl.fyi/issues/305

Change-Id: Icde5a58c6eef98f8984c1e04e980b756dfb76b47
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9341
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
2023-09-20 14:21:32 +00:00

138 lines
3.9 KiB
Nix

# Nix helpers for projects under //tvix
{ pkgs, lib, depot, ... }:
let
# crate override for crates that need protobuf
protobufDep = prev: (prev.nativeBuildInputs or [ ]) ++ [ pkgs.protobuf ];
iconvDarwinDep = lib.optionals pkgs.stdenv.isDarwin [ pkgs.libiconv ];
# Load the crate2nix crate tree.
crates = import ./Cargo.nix {
inherit pkgs;
nixpkgs = pkgs.path;
# Hack to fix Darwin build
# See https://github.com/NixOS/nixpkgs/issues/218712
buildRustCrateForPkgs = pkgs:
if pkgs.stdenv.isDarwin then
let
buildRustCrate = pkgs.buildRustCrate;
buildRustCrate_ = args: buildRustCrate args // { dontStrip = true; };
override = o: args: buildRustCrate.override o (args // { dontStrip = true; });
in
pkgs.makeOverridable override { }
else pkgs.buildRustCrate;
defaultCrateOverrides = pkgs.defaultCrateOverrides // {
zstd-sys = prev: {
nativeBuildInputs = prev.nativeBuildInputs or [ ] ++ iconvDarwinDep;
};
prost-build = prev: {
nativeBuildInputs = protobufDep prev;
};
tonic-reflection = prev: {
nativeBuildInputs = protobufDep prev;
};
tvix-store = prev: {
PROTO_ROOT = depot.tvix.store.protos;
nativeBuildInputs = protobufDep prev;
};
};
};
# Cargo dependencies to be used with nixpkgs rustPlatform functions.
cargoDeps = pkgs.rustPlatform.importCargoLock {
lockFile = ./Cargo.lock;
# Extract the hashes from `crates` / Cargo.nix, we already get them from cargo2nix.
# This returns an attribute set containing "${crateName}-${version}" as key,
# and the outputHash as value.
outputHashes = builtins.listToAttrs
(map
(crateName:
(lib.nameValuePair "${crateName}-${crates.internal.crates.${crateName}.version}" crates.internal.crates.${crateName}.src.outputHash)
) [
"fuse-backend-rs"
"test-generator"
"tonic-mock"
"wu-manber"
]);
};
in
{
inherit crates;
# Run crate2nix generate in the current working directory, then
# format the generated file with depotfmt.
crate2nixGenerate = pkgs.writeShellScriptBin "crate2nix-generate" ''
${pkgs.crate2nix}/bin/crate2nix generate
${depot.tools.depotfmt}/bin/depotfmt Cargo.nix
'';
# Provide the Tvix logo in both .webp and .png format.
logo = pkgs.runCommand "logo"
{
nativeBuildInputs = [ pkgs.imagemagick ];
} ''
mkdir -p $out
cp ${./logo.webp} $out/logo.webp
convert $out/logo.webp $out/logo.png
'';
# Provide a shell for the combined dependencies of all Tvix Rust
# projects. Note that as this is manually maintained it may be
# lacking something, but it is required for some people's workflows.
#
# This shell can be entered with e.g. `mg shell //tvix:shell`.
shell = pkgs.mkShell {
name = "tvix-rust-dev-env";
packages = [
pkgs.buf-language-server
pkgs.cargo
pkgs.clippy
pkgs.evans
pkgs.fuse
pkgs.pkg-config
pkgs.rust-analyzer
pkgs.rustc
pkgs.rustfmt
pkgs.protobuf
] ++ iconvDarwinDep;
};
# Builds and tests the code in store/protos.
store-protos-go = pkgs.buildGoModule {
name = "store-golang";
src = depot.third_party.gitignoreSource ./store/protos;
vendorHash = "sha256-7xfXBBU3xJz7ifjk7Owm/byTfCQ8oaZtqXzBKhLqo00=";
};
# Build the Rust documentation for publishing on docs.tvix.dev.
rust-docs = pkgs.stdenv.mkDerivation {
inherit cargoDeps;
name = "tvix-rust-docs";
src = depot.third_party.gitignoreSource ./.;
PROTO_ROOT = depot.tvix.store.protos;
buildInputs = [
pkgs.fuse
];
nativeBuildInputs = with pkgs; [
cargo
pkg-config
protobuf
rustc
rustPlatform.cargoSetupHook
] ++ iconvDarwinDep;
buildPhase = ''
cargo doc --document-private-items
mv target/doc $out
'';
};
meta.ci.targets = [ "store-protos-go" "shell" "rust-docs" ];
}