diff --git a/backend/posix/posix.go b/backend/posix/posix.go
index da609bf..fe6e42a 100644
--- a/backend/posix/posix.go
+++ b/backend/posix/posix.go
@@ -369,10 +369,9 @@ func (p *Posix) CompleteMultipartUpload(_ context.Context, input *s3.CompleteMul
 	objname := filepath.Join(bucket, object)
 	dir := filepath.Dir(objname)
 	if dir != "" {
-		if err = mkdirAll(dir, os.FileMode(0755), bucket, object); err != nil {
-			if err != nil {
-				return nil, s3err.GetAPIError(s3err.ErrExistingObjectIsDirectory)
-			}
+		err = mkdirAll(dir, os.FileMode(0755), bucket, object)
+		if err != nil {
+			return nil, s3err.GetAPIError(s3err.ErrExistingObjectIsDirectory)
 		}
 	}
 	err = f.link()
diff --git a/backend/scoutfs/scoutfs.go b/backend/scoutfs/scoutfs.go
index 35a6ecb..160a350 100644
--- a/backend/scoutfs/scoutfs.go
+++ b/backend/scoutfs/scoutfs.go
@@ -201,10 +201,9 @@ func (s *ScoutFS) CompleteMultipartUpload(_ context.Context, input *s3.CompleteM
 	objname := filepath.Join(bucket, object)
 	dir := filepath.Dir(objname)
 	if dir != "" {
-		if err = mkdirAll(dir, os.FileMode(0755), bucket, object); err != nil {
-			if err != nil {
-				return nil, s3err.GetAPIError(s3err.ErrExistingObjectIsDirectory)
-			}
+		err = mkdirAll(dir, os.FileMode(0755), bucket, object)
+		if err != nil {
+			return nil, s3err.GetAPIError(s3err.ErrExistingObjectIsDirectory)
 		}
 	}
 	err = f.link()
diff --git a/backend/scoutfs/scoutfs_incompat.go b/backend/scoutfs/scoutfs_incompat.go
index 3776b0b..f88abfa 100644
--- a/backend/scoutfs/scoutfs_incompat.go
+++ b/backend/scoutfs/scoutfs_incompat.go
@@ -34,7 +34,7 @@ var (
 	errNotSupported = errors.New("not supported")
 )
 
-func openTmpFile(dir, bucket, obj string, size int64) (*tmpfile, error) {
+func openTmpFile(_, _, _ string, _ int64) (*tmpfile, error) {
 	return nil, errNotSupported
 }
 
@@ -49,10 +49,10 @@ func (tmp *tmpfile) Write(b []byte) (int, error) {
 func (tmp *tmpfile) cleanup() {
 }
 
-func moveData(from *os.File, to *os.File) error {
+func moveData(_, _ *os.File) error {
 	return errNotSupported
 }
 
-func statMore(path string) (stat, error) {
+func statMore(_ string) (stat, error) {
 	return stat{}, errNotSupported
 }