SGE_PAGE_SIZE
frag_len = min(frag_size, (uint32_t)(SGE_PAGE_SIZE));
m = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, SGE_PAGE_SIZE);
m->m_pkthdr.len = m->m_len = SGE_PAGE_SIZE;
#define SGE_PAGES (SGE_PAGE_SIZE * PAGES_PER_SGE)