lxd/storage/drivers: Remove unnecessary DeleteProject

`DeleteProject` unsets the project for the path unnecessarily since the new project will be set afterwards. And that is an expensive operation since it implies another filepath walk. So this just unsets the quota on the project instead.

Signed-off-by: hamistao <[email protected]>

lxd/storage/drivers/driver_dir_utils.go

@@ -120,14 +120,15 @@ func (d *dir) setQuota(path string, volID int64, sizeBytes int64) error {
 
 	// Clear and create new project if desired project ID is different.
 	if currentProjectID != d.quotaProjectID(volID) {
-		err = quota.DeleteProject(path, currentProjectID)
+		err = quota.SetProject(path, projectID)
 		if err != nil {
-			return err
+			return fmt.Errorf("Failed setting project: %w", err)
 		}
 
-		err = quota.SetProject(path, projectID)
+		// Unset the quota on the current project.
+		err = quota.SetProjectQuota(path, currentProjectID, 0)
 		if err != nil {
-			return fmt.Errorf("Failed setting project: %w", err)
+			return err
 		}
 	}