void if_start(Slirp *slirp) { uint64_t now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); bool from_batchq, next_from_batchq; struct mbuf *ifm, *ifm_next, *ifqt; DEBUG_CALL("if_start"); if (slirp->if_start_busy) { return; } slirp->if_start_busy = true; if (slirp->if_fastq.ifq_next != &slirp->if_fastq) { ifm_next = slirp->if_fastq.ifq_next; next_from_batchq = false; } else if (slirp->next_m != &slirp->if_batchq) { /* Nothing on fastq, pick up from batchq via next_m */ ifm_next = slirp->next_m; next_from_batchq = true; } else { ifm_next = NULL; } while (ifm_next) { ifm = ifm_next; from_batchq = next_from_batchq; ifm_next = ifm->ifq_next; if (ifm_next == &slirp->if_fastq) { /* No more packets in fastq, switch to batchq */ ifm_next = slirp->next_m; next_from_batchq = true; } if (ifm_next == &slirp->if_batchq) { /* end of batchq */ ifm_next = NULL; } /* Try to send packet unless it already expired */ if (ifm->expiration_date >= now && !if_encap(slirp, ifm)) { /* Packet is delayed due to pending ARP resolution */ continue; } if (ifm == slirp->next_m) { /* Set which packet to send on next iteration */ slirp->next_m = ifm->ifq_next; } /* Remove it from the queue */ ifqt = ifm->ifq_prev; remque(ifm); /* If there are more packets for this session, re-queue them */ if (ifm->ifs_next != ifm) { struct mbuf *next = ifm->ifs_next; insque(next, ifqt); ifs_remque(ifm); if (!from_batchq) { /* Next packet in fastq is from the same session */ ifm_next = next; next_from_batchq = false; } else if (slirp->next_m == &slirp->if_batchq) { /* Set next_m and ifm_next if the session packet is now the * only one on batchq */ slirp->next_m = ifm_next = next; } } /* Update so_queued */ if (ifm->ifq_so && --ifm->ifq_so->so_queued == 0) { /* If there's no more queued, reset nqueued */ ifm->ifq_so->so_nqueued = 0; } m_free(ifm); } slirp->if_start_busy = false; }