add dev_random example, remove device field (#81)

* add dev_random example This example illustrates how to use the mount option on partitions. * remove device field from the partition config This field was not used at all in the codebase, having it in the config is misleading. Further on, it seems that there is no point in having it: device files can be mounted through the mount option already. Maybe we can eventually build something where for each partition with at least one device mount we run `udevadm wait --settle <device> [<device>]...` in a satellite thread, and we re-mount a device when it pops back. That way we can re-attach a device without restarting the hypervisor. Further discussion in #80 * refine CI, add prettier --------- Co-authored-by: Wanja Zaeske <[email protected]>
DLR-FT · Jul 19, 2023 · 53bb05e · 53bb05e
1 parent 8ce18f9
commit 53bb05e
Show file tree

Hide file tree

Showing 9 changed files with 143 additions and 57 deletions.
diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
@@ -1,22 +1,53 @@
-name: Run checks
+name: Checks
 
 on:
   pull_request:
   push:
     branches: [main]
 
 jobs:
-  nix-checks:
+  nix-flake-check:
     name: Run nix flake check
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - uses: cachix/install-nix-action@v22
         with:
           github_access_token: ${{ secrets.GITHUB_TOKEN }}
       - uses: cachix/cachix-action@v12
         with:
           name: dlr-ft
-          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
+          authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
       - name: Nix Flake Check
         run: nix flake check
+
+  impure-checks:
+    name: Run check ${{ matrix.check }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        check:
+          - udeps
+          - treefmt --fail-on-change
+          - audit --deny warnings
+    steps:
+      - uses: actions/checkout@v3
+      - uses: cachix/install-nix-action@v22
+        with:
+          github_access_token: ${{ secrets.GITHUB_TOKEN }}
+      - uses: cachix/cachix-action@v12
+        with:
+          name: dlr-ft
+          authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
+      - uses: actions/cache@v3
+        with:
+          path: |
+            ~/.cargo/bin/
+            ~/.cargo/registry/index/
+            ~/.cargo/registry/cache/
+            ~/.cargo/git/db/
+            target/
+          key: ${{ runner.os }}-${{ github.job }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+      - name: Run check ${{ matrix.check }}
+        run: nix develop --command ${{ matrix.check }}
diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
@@ -16,54 +16,29 @@ jobs:
           - hello_part
           - fuel_tank
           - ping
+          - dev_random
     env:
       DURATION: 10s
       RUST_LOG: trace
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - uses: cachix/install-nix-action@v22
         with:
           github_access_token: ${{ secrets.GITHUB_TOKEN }}
       - uses: cachix/cachix-action@v12
         with:
           name: dlr-ft
-          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
+          authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
+      - uses: actions/cache@v3
+        with:
+          path: |
+            ~/.cargo/bin/
+            ~/.cargo/registry/index/
+            ~/.cargo/registry/cache/
+            ~/.cargo/git/db/
+            target/
+          key: ${{ runner.os }}-${{ github.job }}-${{ matrix.example }}-cargo-${{ hashFiles('**/Cargo.lock') }}
       - name: Check CGroup
         run: systemd-run --user --scope cat /proc/self/cgroup
       - name: Run example ${{ matrix.example }}
-        run: nix develop --command systemd-run-example-${{ matrix.example }} --duration $DURATION  
-
-  checks:
-    name: Run check ${{ matrix.check }}
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        check:
-          - udeps
-          - treefmt --fail-on-change
-          - audit --deny warnings
-    steps:
-      - uses: actions/checkout@v2
-      - uses: cachix/install-nix-action@v13
-        with:
-          nix_path: nixpkgs=channel:nixos-stable
-          extra_nix_config: |
-            experimental-features = nix-command flakes
-            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
-      - name: Cache Nix store
-        uses: actions/cache@v3
-        id: nix-cache
-        with:
-          path: /tmp/nixcache
-          key: nix-${{ runner.os }}
-      - name: Import Nix store cache
-        if: "steps.nix-cache.outputs.cache-hit == 'true'"
-        run: nix copy --no-check-sigs --from /tmp/nixcache --all
-      - name: Run check ${{ matrix.check }}
-        run: nix develop --command ${{ matrix.check }}
-      - name: Export Nix store cache
-        if: "steps.nix-cache.outputs.cache-hit != 'true'"
-        run: |
-          nix copy --no-check-sigs --to /tmp/nixcache \
-            .#devShells.x86_64-linux.default
+        run: nix develop --command systemd-run-example-${{ matrix.example }} --duration $DURATION
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -1,4 +1,5 @@
 [workspace]
+resolver = "2"
 
 members = [
     "hypervisor",
@@ -12,6 +13,8 @@ members = [
 
     "examples/ping_client",
     "examples/ping_server",
+
+    "examples/dev_random",
 ]
 
 [workspace.dependencies]

diff --git a/examples/dev_random.yaml b/examples/dev_random.yaml
@@ -0,0 +1,10 @@
+major_frame: 1s
+partitions:
+  - id: 0
+    name: partition_0
+    duration: 1s
+    offset: 0ms
+    period: 1s
+    image: target/x86_64-unknown-linux-musl/release/dev_random
+    mounts:
+      - [/dev/random, /dev/random]
diff --git a/examples/dev_random/Cargo.toml b/examples/dev_random/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "dev_random"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+a653rs = { workspace = true, features = ["macros"] }
+a653rs-linux = { path = "../../partition" }
+log.workspace = true
diff --git a/examples/dev_random/src/main.rs b/examples/dev_random/src/main.rs
@@ -0,0 +1,55 @@
+use a653rs::partition;
+use a653rs::prelude::PartitionExt;
+use a653rs_linux::partition::ApexLogger;
+use log::LevelFilter;
+
+fn main() {
+    ApexLogger::install_panic_hook();
+    ApexLogger::install_logger(LevelFilter::Trace).unwrap();
+
+    dev_random::Partition.run()
+}
+
+#[partition(a653rs_linux::partition::ApexLinuxPartition)]
+mod dev_random {
+    use log::info;
+    use std::{fs::*, io::Read};
+
+    #[start(cold)]
+    fn cold_start(mut ctx: start::Context) {
+        // create and start an aperiodic process
+        ctx.create_process_0().unwrap().start().unwrap();
+    }
+
+    // do the same as a cold_start
+    #[start(warm)]
+    fn warm_start(ctx: start::Context) {
+        cold_start(ctx);
+    }
+
+    // this aperiodic process opens /dev/random and reads some random bytes from it
+    #[aperiodic(
+        time_capacity = "Infinite",
+        stack_size = "8KB",
+        base_priority = 1,
+        deadline = "Soft"
+    )]
+    fn process_0(_: process_0::Context) {
+        info!("started process_0");
+
+        // open the device file and read its metadata
+        let filename = "/dev/random";
+        let mut f = File::open(&filename).expect("no file found");
+        let metadata = metadata(&filename).expect("unable to read metadata");
+        info!("metadata: {metadata:#?}");
+
+        // read 16 bytes from the device
+        let mut buffer = [0u8; 16];
+        f.read(&mut buffer).expect("buffer overflow");
+        info!("got some randomness: {buffer:?}");
+
+        info!("terminating this partitiong by setting the operating mode to idle");
+        // TODO wait for https://github.com/DLR-FT/a653rs/issues/22 to be fixed
+        // Hypervisor::set_partition_mode(OperatingMode::Idle);
+    }
+}
diff --git a/flake.nix b/flake.nix
@@ -72,6 +72,10 @@
             name = "ping";
             partitions = [ "ping_server" "ping_client" ];
           }
+          {
+            name = "dev_random";
+            partitions = [ "dev_random" ];
+          }
         ];
 
         cargoPackageList = ps: builtins.map (p: "--package=${p}") ps;
@@ -116,6 +120,7 @@
             cargo-audit
             cargo-expand
             nixpkgs-fmt
+            nodePackages.prettier
           ];
           git.hooks = {
             enable = true;

diff --git a/hypervisor/src/hypervisor/config.rs b/hypervisor/src/hypervisor/config.rs
@@ -122,31 +122,18 @@ pub struct Partition {
     /// Path to the executable of the partition
     pub image: PathBuf,
 
-    /// Devices to be mounted into the partitions namespace
-    ///
-    /// Use this to pass devices into the partition, i. e. to get access to a
-    /// physical serial port.
-    #[serde(default)]
-    pub devices: Vec<Device>,
-
     // TODO
     #[serde(default)]
     pub hm_table: PartitionHMTable,
 
     /// Bindmounts from host to partition
     ///
-    /// Use this to expose a path from the host environment inside of a
-    /// partitions mnt namespace
+    /// Use this to expose a path / file / device file from the host environment
+    /// to the inside of a partitions.
     #[serde(default)]
     pub mounts: Vec<(PathBuf, PathBuf)>,
 }
 
-#[derive(Debug, Serialize, Deserialize, Clone)]
-pub struct Device {
-    pub path: PathBuf,
-    pub read_only: bool,
-}
-
 #[derive(Debug, Serialize, Deserialize, Clone)]
 pub enum Channel {
     Queuing(QueuingChannelConfig),