fix possible dm snapshot leaks

pkg/dmlegacy/vm.go

@@ -83,16 +83,17 @@ func AllocateAndPopulateOverlay(vm *api.VM) error {
 }
 
 func copyToOverlay(vm *api.VM) error {
- if err := ActivateSnapshot(vm); err != nil {
+ err := ActivateSnapshot(vm)
+ defer cleanup.DeactivateSnapshot(vm)
+ if err != nil {
  return err
  }
- defer cleanup.DeactivateSnapshot(vm)
 
  mp, err := util.Mount(vm.SnapshotDev())
+ defer mp.Umount()
  if err != nil {
  return err
  }
- defer mp.Umount()
 
  // Copy the kernel files to the VM. TODO: Use snapshot overlaying instead.
  if err := copyKernelToOverlay(vm, mp.Path); err != nil {

pkg/operations/remove.go

@@ -6,6 +6,7 @@ import (
  log "github.com/sirupsen/logrus"
  api "github.com/weaveworks/ignite/pkg/apis/ignite"
  "github.com/weaveworks/ignite/pkg/client"
+ "github.com/weaveworks/ignite/pkg/dmlegacy/cleanup"
  "github.com/weaveworks/ignite/pkg/logs"
  "github.com/weaveworks/ignite/pkg/providers"
  "github.com/weaveworks/ignite/pkg/runtime"
@@ -28,7 +29,7 @@ func DeleteVM(c *client.Client, vm *api.VM) error {
 // CleanupVM removes the resources of the given VM
 func CleanupVM(vm *api.VM) error {
  // Inspect the container before trying to stop it and it gets auto-removed
- result, _ := providers.Runtime.InspectContainer(util.NewPrefixer().Prefix(vm.GetUID()))
+ inspectResult, _ := providers.Runtime.InspectContainer(util.NewPrefixer().Prefix(vm.GetUID()))
 
  // If the VM is running, try to kill it first so we don't leave dangling containers
  if vm.Running() {
@@ -38,7 +39,13 @@ func CleanupVM(vm *api.VM) error {
  }
 
  // Remove the VM container if it exists
- RemoveVMContainer(result)
+ // TODO should this function return a proper error?
+ RemoveVMContainer(inspectResult)
+
+ // After removal is successful, remove the dm snapshots
+ if err := cleanup.DeactivateSnapshot(vm); err != nil {
+ return err
+ }
 
  if logs.Quiet {
  fmt.Println(vm.GetUID())