diff --git a/pkg/storage/fs/ocis/node.go b/pkg/storage/fs/ocis/node.go
index 3d15fd43c28..1b763dd16ba 100644
--- a/pkg/storage/fs/ocis/node.go
+++ b/pkg/storage/fs/ocis/node.go
@@ -148,10 +148,16 @@ func ReadNode(ctx context.Context, lu *Lookup, id string) (n *Node, err error) {
 
 	// lookup parent id in extended attributes
 	var attrBytes []byte
-	if attrBytes, err = xattr.Get(nodePath, parentidAttr); err == nil {
+	attrBytes, err = xattr.Get(nodePath, parentidAttr)
+	switch {
+	case err == nil:
 		n.ParentID = string(attrBytes)
-	} else {
-		return
+	case isNoData(err):
+		return nil, errtypes.InternalError(err.Error())
+	case isNotFound(err):
+		return nil, errtypes.NotFound(n.ID)
+	default:
+		return nil, errtypes.InternalError(err.Error())
 	}
 	// lookup name in extended attributes
 	if attrBytes, err = xattr.Get(nodePath, nameAttr); err == nil {
diff --git a/pkg/storage/fs/ocis/ocis.go b/pkg/storage/fs/ocis/ocis.go
index bd1eb9e94ec..8d41907cb89 100644
--- a/pkg/storage/fs/ocis/ocis.go
+++ b/pkg/storage/fs/ocis/ocis.go
@@ -224,16 +224,19 @@ func (fs *ocisfs) GetPathByID(ctx context.Context, id *provider.ResourceId) (str
 }
 
 func (fs *ocisfs) CreateDir(ctx context.Context, fn string) (err error) {
-	var node *Node
-	if node, err = fs.lu.NodeFromPath(ctx, fn); err != nil {
+	var n *Node
+	if n, err = fs.lu.NodeFromPath(ctx, fn); err != nil {
 		return
 	}
 
-	if node.Exists {
+	if n.Exists {
 		return errtypes.AlreadyExists(fn)
 	}
 
-	pn, err := node.Parent()
+	pn, err := n.Parent()
+	if err != nil {
+		return errors.Wrap(err, "ocisfs: error getting parent "+n.ParentID)
+	}
 	ok, err := fs.p.HasPermission(ctx, pn, func(rp *provider.ResourcePermissions) bool {
 		return rp.CreateContainer
 	})
@@ -241,16 +244,16 @@ func (fs *ocisfs) CreateDir(ctx context.Context, fn string) (err error) {
 	case err != nil:
 		return errtypes.InternalError(err.Error())
 	case !ok:
-		return errtypes.PermissionDenied(filepath.Join(node.ParentID, node.Name))
+		return errtypes.PermissionDenied(filepath.Join(n.ParentID, n.Name))
 	}
 
-	err = fs.tp.CreateDir(ctx, node)
+	err = fs.tp.CreateDir(ctx, n)
 
 	if fs.o.TreeTimeAccounting {
-		nodePath := node.lu.toInternalPath(node.ID)
+		nodePath := n.lu.toInternalPath(n.ID)
 		// mark the home node as the end of propagation
 		if err = xattr.Set(nodePath, propagationAttr, []byte("1")); err != nil {
-			appctx.GetLogger(ctx).Error().Err(err).Interface("node", node).Msg("could not mark node to propagate")
+			appctx.GetLogger(ctx).Error().Err(err).Interface("node", n).Msg("could not mark node to propagate")
 			return
 		}
 	}
diff --git a/pkg/storage/fs/ocis/option.go b/pkg/storage/fs/ocis/option.go
index 198075d979c..e8ee62464a7 100644
--- a/pkg/storage/fs/ocis/option.go
+++ b/pkg/storage/fs/ocis/option.go
@@ -43,6 +43,7 @@ type Options struct {
 }
 
 // newOptions initializes the available default options.
+/* for future use, commented to make linter happy
 func newOptions(opts ...Option) Options {
 	opt := Options{}
 
@@ -52,6 +53,7 @@ func newOptions(opts ...Option) Options {
 
 	return opt
 }
+*/
 
 // Root provides a function to set the root option.
 func Root(val string) Option {
diff --git a/pkg/storage/fs/ocis/permissions.go b/pkg/storage/fs/ocis/permissions.go
index fef8e60e988..6dcfd9c4e30 100644
--- a/pkg/storage/fs/ocis/permissions.go
+++ b/pkg/storage/fs/ocis/permissions.go
@@ -26,8 +26,8 @@ import (
 	userv1beta1 "github.com/cs3org/go-cs3apis/cs3/identity/user/v1beta1"
 	provider "github.com/cs3org/go-cs3apis/cs3/storage/provider/v1beta1"
 	"github.com/cs3org/reva/pkg/appctx"
-	"github.com/cs3org/reva/pkg/storage/utils/ace"
 	"github.com/cs3org/reva/pkg/user"
+	"github.com/pkg/errors"
 	"github.com/pkg/xattr"
 )
 
@@ -136,7 +136,7 @@ func (p *Permissions) HasPermission(ctx context.Context, n *Node, check func(*pr
 		}
 
 		if cn, err = cn.Parent(); err != nil {
-			return false, err
+			return false, errors.Wrap(err, "ocisfs: error getting parent "+cn.ParentID)
 		}
 	}
 
@@ -185,14 +185,3 @@ func isNotFound(err error) bool {
 	}
 	return false
 }
-
-func (fs *ocisfs) readACE(ctx context.Context, ip string, principal string) (e *ace.ACE, err error) {
-	var b []byte
-	if b, err = xattr.Get(ip, grantPrefix+principal); err != nil {
-		return nil, err
-	}
-	if e, err = ace.Unmarshal(principal, b); err != nil {
-		return nil, err
-	}
-	return
-}
diff --git a/pkg/storage/fs/ocis/revisions.go b/pkg/storage/fs/ocis/revisions.go
index 816aa6c1ea6..898cd5c3487 100644
--- a/pkg/storage/fs/ocis/revisions.go
+++ b/pkg/storage/fs/ocis/revisions.go
@@ -90,6 +90,9 @@ func (fs *ocisfs) DownloadRevision(ctx context.Context, ref *provider.Reference,
 
 	// check if the node is available and has not been deleted
 	n, err := ReadNode(ctx, fs.lu, kp[0])
+	if err != nil {
+		return nil, err
+	}
 	if !n.Exists {
 		err = errtypes.NotFound(filepath.Join(n.ParentID, n.Name))
 		return nil, err
@@ -130,6 +133,9 @@ func (fs *ocisfs) RestoreRevision(ctx context.Context, ref *provider.Reference,
 
 	// check if the node is available and has not been deleted
 	n, err := ReadNode(ctx, fs.lu, kp[0])
+	if err != nil {
+		return err
+	}
 	if !n.Exists {
 		err = errtypes.NotFound(filepath.Join(n.ParentID, n.Name))
 		return err
diff --git a/pkg/storage/fs/ocis/tree.go b/pkg/storage/fs/ocis/tree.go
index 63cb090935e..f58390cabe5 100644
--- a/pkg/storage/fs/ocis/tree.go
+++ b/pkg/storage/fs/ocis/tree.go
@@ -225,12 +225,12 @@ func (t *Tree) ListFolder(ctx context.Context, node *Node) ([]*Node, error) {
 }
 
 // Delete deletes a node in the tree
-func (t *Tree) Delete(ctx context.Context, node *Node) (err error) {
+func (t *Tree) Delete(ctx context.Context, n *Node) (err error) {
 
 	// Prepare the trash
 	// TODO use layout?, but it requires resolving the owners user if the username is used instead of the id.
 	// the node knows the owner id so we use that for now
-	ownerid, _, err := node.Owner()
+	ownerid, _, err := n.Owner()
 	if err != nil {
 		return
 	}
@@ -244,13 +244,13 @@ func (t *Tree) Delete(ctx context.Context, node *Node) (err error) {
 	}
 
 	// get the original path
-	origin, err := t.lu.Path(ctx, node)
+	origin, err := t.lu.Path(ctx, n)
 	if err != nil {
 		return
 	}
 
 	// set origin location in metadata
-	nodePath := t.lu.toInternalPath(node.ID)
+	nodePath := t.lu.toInternalPath(n.ID)
 	if err := xattr.Set(nodePath, trashOriginAttr, []byte(origin)); err != nil {
 		return err
 	}
@@ -259,8 +259,8 @@ func (t *Tree) Delete(ctx context.Context, node *Node) (err error) {
 
 	// first make node appear in the owners (or root) trash
 	// parent id and name are stored as extended attributes in the node itself
-	trashLink := filepath.Join(t.lu.Options.Root, "trash", ownerid, node.ID)
-	err = os.Symlink("../nodes/"+node.ID+".T."+deletionTime, trashLink)
+	trashLink := filepath.Join(t.lu.Options.Root, "trash", ownerid, n.ID)
+	err = os.Symlink("../nodes/"+n.ID+".T."+deletionTime, trashLink)
 	if err != nil {
 		// To roll back changes
 		// TODO unset trashOriginAttr
@@ -280,7 +280,7 @@ func (t *Tree) Delete(ctx context.Context, node *Node) (err error) {
 	}
 
 	// finally remove the entry from the parent dir
-	src := filepath.Join(t.lu.toInternalPath(node.ParentID), node.Name)
+	src := filepath.Join(t.lu.toInternalPath(n.ParentID), n.Name)
 	err = os.Remove(src)
 	if err != nil {
 		// To roll back changes
@@ -290,9 +290,9 @@ func (t *Tree) Delete(ctx context.Context, node *Node) (err error) {
 		return
 	}
 
-	p, err := node.Parent()
+	p, err := n.Parent()
 	if err != nil {
-		return
+		return errors.Wrap(err, "ocisfs: error getting parent "+n.ParentID)
 	}
 	return t.Propagate(ctx, p)
 }
diff --git a/pkg/storage/fs/ocis/upload.go b/pkg/storage/fs/ocis/upload.go
index ec065838e78..335aeb2aaec 100644
--- a/pkg/storage/fs/ocis/upload.go
+++ b/pkg/storage/fs/ocis/upload.go
@@ -44,11 +44,11 @@ var defaultFilePerm = os.FileMode(0664)
 
 // TODO deprecated ... use tus
 
-func (fs *ocisfs) Upload(ctx context.Context, ref *provider.Reference, r io.ReadCloser) error {
+func (fs *ocisfs) Upload(ctx context.Context, ref *provider.Reference, r io.ReadCloser) (err error) {
 
-	n, err := fs.lu.NodeFromResource(ctx, ref)
-	if err != nil {
-		return err
+	var n *Node
+	if n, err = fs.lu.NodeFromResource(ctx, ref); err != nil {
+		return
 	}
 
 	// check permissions
@@ -60,9 +60,9 @@ func (fs *ocisfs) Upload(ctx context.Context, ref *provider.Reference, r io.Read
 		})
 	} else {
 		// check permissions of parent
-		p, err := n.Parent()
-		if err != nil {
-			return errors.Wrap(err, "ocisfs: error getting parent "+n.ParentID)
+		p, perr := n.Parent()
+		if perr != nil {
+			return errors.Wrap(perr, "ocisfs: error getting parent "+n.ParentID)
 		}
 
 		ok, err = fs.p.HasPermission(ctx, p, func(rp *provider.ResourcePermissions) bool {
@@ -82,7 +82,8 @@ func (fs *ocisfs) Upload(ctx context.Context, ref *provider.Reference, r io.Read
 
 	nodePath := fs.lu.toInternalPath(n.ID)
 
-	tmp, err := ioutil.TempFile(nodePath, "._reva_atomic_upload")
+	var tmp *os.File
+	tmp, err = ioutil.TempFile(nodePath, "._reva_atomic_upload")
 	if err != nil {
 		return errors.Wrap(err, "ocisfs: error creating tmp fn at "+nodePath)
 	}
@@ -96,9 +97,8 @@ func (fs *ocisfs) Upload(ctx context.Context, ref *provider.Reference, r io.Read
 	//_ = os.RemoveAll(path.Join(nodePath, "content"))
 	appctx.GetLogger(ctx).Warn().Msg("TODO move old content to version")
 
-	err = os.Rename(tmp.Name(), nodePath)
-	if err != nil {
-		return err
+	if err = os.Rename(tmp.Name(), nodePath); err != nil {
+		return
 	}
 
 	if fs.o.EnableHome {
@@ -113,19 +113,18 @@ func (fs *ocisfs) Upload(ctx context.Context, ref *provider.Reference, r io.Read
 		err = n.writeMetadata(nil)
 	}
 	if err != nil {
-		return err
+		return
 	}
 
 	if fs.o.TreeTimeAccounting {
 		// mark the home node as the end of propagation q
 		if err = xattr.Set(nodePath, propagationAttr, []byte("1")); err != nil {
 			appctx.GetLogger(ctx).Error().Err(err).Interface("node", n).Msg("could not mark node to propagate")
-			return err
+			return
 		}
 	}
 
 	return fs.tp.Propagate(ctx, n)
-
 }
 
 // InitiateUpload returns an upload id that can be used for uploads with tus
@@ -217,9 +216,9 @@ func (fs *ocisfs) NewUpload(ctx context.Context, info tusd.FileInfo) (upload tus
 		})
 	} else {
 		// check permissions of parent
-		p, err := n.Parent()
-		if err != nil {
-			return nil, errors.Wrap(err, "ocisfs: error getting parent "+n.ParentID)
+		p, perr := n.Parent()
+		if perr != nil {
+			return nil, errors.Wrap(perr, "ocisfs: error getting parent "+n.ParentID)
 		}
 
 		ok, err = fs.p.HasPermission(ctx, p, func(rp *provider.ResourcePermissions) bool {