Re-add locks to volumes.

This will require a 'podman system renumber' after being applied
to get lock numbers for existing volumes.

Add the DB backend code for rewriting volume configs and use it
for updating lock numbers as part of 'system renumber'.

Signed-off-by: Matthew Heon <matthew.heon@pm.me>

1 files changed, 45 insertions, 1 deletions

diff --git a/libpod/boltdb_state.go b/libpod/boltdb_state.go
index 176781f07..1de8d80c9 100644
--- a/libpod/boltdb_state.go
+++ b/libpod/boltdb_state.go
@@ -870,7 +870,7 @@ func (s *BoltState) RewritePodConfig(pod *Pod, newCfg *PodConfig) error {
 
 	newCfgJSON, err := json.Marshal(newCfg)
 	if err != nil {
-		return errors.Wrapf(err, "error marshalling new configuration JSON for container %s", pod.ID())
+		return errors.Wrapf(err, "error marshalling new configuration JSON for pod %s", pod.ID())
 	}
 
 	db, err := s.getDBCon()
@@ -900,6 +900,50 @@ func (s *BoltState) RewritePodConfig(pod *Pod, newCfg *PodConfig) error {
 	return err
 }
 
+// RewriteVolumeConfig rewrites a volume's configuration.
+// WARNING: This function is DANGEROUS. Do not use without reading the full
+// comment on this function in state.go.
+func (s *BoltState) RewriteVolumeConfig(volume *Volume, newCfg *VolumeConfig) error {
+	if !s.valid {
+		return define.ErrDBClosed
+	}
+
+	if !volume.valid {
+		return define.ErrVolumeRemoved
+	}
+
+	newCfgJSON, err := json.Marshal(newCfg)
+	if err != nil {
+		return errors.Wrapf(err, "error marshalling new configuration JSON for volume %q", volume.Name())
+	}
+
+	db, err := s.getDBCon()
+	if err != nil {
+		return err
+	}
+	defer s.deferredCloseDBCon(db)
+
+	err = db.Update(func(tx *bolt.Tx) error {
+		volBkt, err := getVolBucket(tx)
+		if err != nil {
+			return err
+		}
+
+		volDB := volBkt.Bucket([]byte(volume.Name()))
+		if volDB == nil {
+			volume.valid = false
+			return errors.Wrapf(define.ErrNoSuchVolume, "no volume with name %q found in DB", volume.Name())
+		}
+
+		if err := volDB.Put(configKey, newCfgJSON); err != nil {
+			return errors.Wrapf(err, "error updating volume %q config JSON", volume.Name())
+		}
+
+		return nil
+	})
+	return err
+}
+
 // Pod retrieves a pod given its full ID
 func (s *BoltState) Pod(id string) (*Pod, error) {
 	if id == "" {