virtcontainers: revert "fix shared dir resource remaining"

This reverts commit 8a6d383.

Don't remove all directories in the shared directory because
`docker cp` re-mounts all the mount points specified in the
config.json causing serious problems in the host.

fixes #777

Signed-off-by: Julio Montes <[email protected]>

virtcontainers/agent.go

@@ -155,9 +155,6 @@ type agent interface {
 	// stopSandbox will tell the agent to stop all containers related to the Sandbox.
 	stopSandbox(sandbox *Sandbox) error
 
-	// cleanup will clean the resources for sandbox
-	cleanupSandbox(sandbox *Sandbox) error
-
 	// createContainer will tell the agent to create a container related to a Sandbox.
 	createContainer(sandbox *Sandbox, c *Container) (*Process, error)
 

virtcontainers/container.go

@@ -505,19 +505,11 @@ func (c *Container) mountSharedDirMounts(hostSharedDir, guestSharedDir string) (
 func (c *Container) unmountHostMounts() error {
 	for _, m := range c.mounts {
 		if m.HostPath != "" {
-			logger := c.Logger().WithField("host-path", m.HostPath)
 			if err := syscall.Unmount(m.HostPath, 0); err != nil {
-				// Unable to unmount paths could be a really big problem here
-				// we need to make sure cause 'less damage' if things are
-				// really broken. For further, we need to give admins more of
-				// a chance to diagnose the problem. As the rules of `fail fast`,
-				// here we return an error as soon as we get it.
-				logger.WithError(err).Warn("Could not umount")
-				return err
-			} else if err := os.RemoveAll(m.HostPath); err != nil {
-				// since the mounts related to the shared dir is umounted
-				// we need to remove the host path to avoid resource remaining
-				logger.WithError(err).Warn("Could not be removed")
+				c.Logger().WithFields(logrus.Fields{
+					"host-path": m.HostPath,
+					"error":     err,
+				}).Warn("Could not umount")
 				return err
 			}
 		}

virtcontainers/hyperstart_agent.go

@@ -897,10 +897,6 @@ func (h *hyper) resumeContainer(sandbox *Sandbox, c Container) error {
 	return nil
 }
 
-func (h *hyper) cleanupSandbox(sandbox *Sandbox) error {
-	return nil
-}
-
 func (h *hyper) reseedRNG(data []byte) error {
 	// hyperstart-agent does not support reseeding
 	return nil

virtcontainers/kata_agent.go

@@ -604,10 +604,6 @@ func (k *kataAgent) stopSandbox(sandbox *Sandbox) error {
 	return k.proxy.stop(sandbox, k.state.ProxyPid)
 }
 
-func (k *kataAgent) cleanupSandbox(sandbox *Sandbox) error {
-	return os.RemoveAll(filepath.Join(kataHostSharedDir, sandbox.id))
-}
-
 func (k *kataAgent) replaceOCIMountSource(spec *specs.Spec, guestMounts []Mount) error {
 	ociMounts := spec.Mounts
 
@@ -1072,14 +1068,7 @@ func (k *kataAgent) stopContainer(sandbox *Sandbox, c Container) error {
 		return err
 	}
 
-	if err := bindUnmountContainerRootfs(kataHostSharedDir, sandbox.id, c.id); err != nil {
-		return err
-	}
-
-	// since rootfs is umounted it's safe to remove the dir now
-	rootPathParent := filepath.Join(kataHostSharedDir, sandbox.id, c.id)
-
-	return os.RemoveAll(rootPathParent)
+	return bindUnmountContainerRootfs(kataHostSharedDir, sandbox.id, c.id)
 }
 
 func (k *kataAgent) signalProcess(c *Container, processID string, signal syscall.Signal, all bool) error {

virtcontainers/noop_agent.go

@@ -56,11 +56,6 @@ func (n *noopAgent) stopSandbox(sandbox *Sandbox) error {
 	return nil
 }
 
-// cleanup is the Noop agent clean up resource implementation. It does nothing.
-func (n *noopAgent) cleanupSandbox(sandbox *Sandbox) error {
-	return nil
-}
-
 // createContainer is the Noop agent Container creation implementation. It does nothing.
 func (n *noopAgent) createContainer(sandbox *Sandbox, c *Container) (*Process, error) {
 	return &Process{}, nil

virtcontainers/sandbox.go

@@ -1258,13 +1258,6 @@ func (s *Sandbox) stop() error {
 		return err
 	}
 
-	// vm is stopped remove the sandbox shared dir
-	if err := s.agent.cleanupSandbox(s); err != nil {
-		// cleanup resource failed shouldn't block destroy sandbox
-		// just raise a warning
-		s.Logger().WithError(err).Warnf("cleanup sandbox failed")
-	}
-
 	return s.setSandboxState(StateStopped)
 }