From 5ba438d1e173654dd955d167052b65cf3220c2cd Mon Sep 17 00:00:00 2001
From: Thomas Schubart <thomas@gitpod.io>
Date: Mon, 28 Feb 2022 17:24:40 +0000
Subject: [PATCH] Add runc-facade

---
 components/ws-daemon/gp-runc/main.go        | 75 +++++++++++++++++++++
 components/ws-daemon/pkg/cpulimit/cfs_cg.go | 20 ++++++
 components/ws-daemon/pkg/cpulimit/cfs_v2.go |  1 +
 3 files changed, 96 insertions(+)
 create mode 100644 components/ws-daemon/gp-runc/main.go
 create mode 100644 components/ws-daemon/pkg/cpulimit/cfs_cg.go

diff --git a/components/ws-daemon/gp-runc/main.go b/components/ws-daemon/gp-runc/main.go
new file mode 100644
index 00000000000000..c3413216b60edc
--- /dev/null
+++ b/components/ws-daemon/gp-runc/main.go
@@ -0,0 +1,75 @@
+package main
+
+import (
+	"encoding/json"
+	"os"
+	"os/exec"
+	"syscall"
+
+	"github.com/opencontainers/runtime-spec/specs-go"
+	"github.com/sirupsen/logrus"
+	"golang.org/x/xerrors"
+)
+
+var (
+	fuseDeviceMajor int64 = 10
+	fuseDeviceMinor int64 = 229
+)
+
+func main() {
+	log := logrus.New()
+	log.SetLevel(logrus.DebugLevel)
+
+	var err error
+	runcPath, err := exec.LookPath("runc.orig")
+	if err != nil {
+		log.WithError(err).Fatal("runc not found")
+	}
+
+	var useFacade bool
+	for _, arg := range os.Args {
+		if arg == "create" {
+			useFacade = true
+			break
+		}
+	}
+
+	if useFacade {
+		err = createAndRunc(runcPath, log)
+	} else {
+		err = syscall.Exec(runcPath, os.Args, os.Environ())
+	}
+	if err != nil {
+		log.WithError(err).Fatal("failed")
+	}
+}
+
+func createAndRunc(runcPath string, log *logrus.Logger) error {
+	fc, err := os.ReadFile("config.json")
+	if err != nil {
+		return xerrors.Errorf("cannot read config.json: %w", err)
+	}
+
+	var cfg specs.Spec
+	err = json.Unmarshal(fc, &cfg)
+	if err != nil {
+		return xerrors.Errorf("cannot decode config.json: %w", err)
+	}
+
+	fuseDevice := specs.LinuxDeviceCgroup{
+		Type:   "c",
+		Minor:  &fuseDeviceMinor,
+		Major:  &fuseDeviceMajor,
+		Access: "rwm",
+		Allow:  true,
+	}
+
+	cfg.Linux.Resources.Devices = append(cfg.Linux.Resources.Devices, fuseDevice)
+
+	err = syscall.Exec(runcPath, os.Args, os.Environ())
+	if err != nil {
+		return xerrors.Errorf("exec %s: %w", runcPath, err)
+	}
+
+	return nil
+}
diff --git a/components/ws-daemon/pkg/cpulimit/cfs_cg.go b/components/ws-daemon/pkg/cpulimit/cfs_cg.go
new file mode 100644
index 00000000000000..ba2bfd5f904901
--- /dev/null
+++ b/components/ws-daemon/pkg/cpulimit/cfs_cg.go
@@ -0,0 +1,20 @@
+package cpulimit
+
+import (
+"github.com/containerd/cgroups"
+)
+
+type CFSControllerCgroup struct {
+	cgroup cgroups.Cgroup
+}
+
+func Load(base string) (CFSControllerCgroup, error) {
+	cgroup, err := cgroups.Load(cgroups.V1, cgroups.StaticPath(base))
+	if err != nil {
+		return CFSControllerCgroup{}, err
+	}
+
+	return CFSControllerCgroup{
+		cgroup: cgroup,
+	}, nil
+}
\ No newline at end of file
diff --git a/components/ws-daemon/pkg/cpulimit/cfs_v2.go b/components/ws-daemon/pkg/cpulimit/cfs_v2.go
index 1b2a133171e554..4d3c9716697530 100644
--- a/components/ws-daemon/pkg/cpulimit/cfs_v2.go
+++ b/components/ws-daemon/pkg/cpulimit/cfs_v2.go
@@ -20,6 +20,7 @@ import (
 type CgroupV2CFSController string
 
 func (basePath CgroupV2CFSController) Usage() (CPUTime, error) {
+
 	usage, err := basePath.getFlatKeyedValue("usage_usec")
 	if err != nil {
 		return 0, err