M_VLANTAG
m->m_flags |= M_VLANTAG;
KASSERT(m->m_flags & M_VLANTAG);
return (m->m_flags & M_VLANTAG) != 0;
m->m_flags &= ~M_VLANTAG;
m->m_flags &= ~M_VLANTAG;
m->m_flags &= ~M_VLANTAG;
M_VLANTAG)