disc: Avoid warnings when the volume doesn't have a mount
disc: Avoid warnings when the volume doesn't have a mount

MathieuDuponchelle/totem-pl-parser,MathieuDuponchelle/totem-pl-parser,MathieuDuponchelle/totem-pl-parser,pwithnall/totem-pl-parser,pwithnall/totem-pl-parser,MathieuDuponchelle/totem-pl-parser