diff options
Diffstat (limited to 'slirp/src/if.c')
| m--------- | slirp | 0 | ||||
| -rw-r--r-- | slirp/src/if.c | 218 |
2 files changed, 0 insertions, 218 deletions
diff --git a/slirp b/slirp new file mode 160000 +Subproject 59a1b1f165458c2acb7ff0525b543945f741622 diff --git a/slirp/src/if.c b/slirp/src/if.c deleted file mode 100644 index 6eaac72..0000000 --- a/slirp/src/if.c +++ /dev/null @@ -1,218 +0,0 @@ -/* SPDX-License-Identifier: BSD-3-Clause */ -/* - * Copyright (c) 1995 Danny Gasparovski. - */ - -#include "slirp.h" - -static void -ifs_insque(struct mbuf *ifm, struct mbuf *ifmhead) -{ - ifm->ifs_next = ifmhead->ifs_next; - ifmhead->ifs_next = ifm; - ifm->ifs_prev = ifmhead; - ifm->ifs_next->ifs_prev = ifm; -} - -static void -ifs_remque(struct mbuf *ifm) -{ - ifm->ifs_prev->ifs_next = ifm->ifs_next; - ifm->ifs_next->ifs_prev = ifm->ifs_prev; -} - -void -if_init(Slirp *slirp) -{ - slirp->if_fastq.qh_link = slirp->if_fastq.qh_rlink = &slirp->if_fastq; - slirp->if_batchq.qh_link = slirp->if_batchq.qh_rlink = &slirp->if_batchq; -} - -/* - * if_output: Queue packet into an output queue. - * There are 2 output queue's, if_fastq and if_batchq. - * Each output queue is a doubly linked list of double linked lists - * of mbufs, each list belonging to one "session" (socket). This - * way, we can output packets fairly by sending one packet from each - * session, instead of all the packets from one session, then all packets - * from the next session, etc. Packets on the if_fastq get absolute - * priority, but if one session hogs the link, it gets "downgraded" - * to the batchq until it runs out of packets, then it'll return - * to the fastq (eg. if the user does an ls -alR in a telnet session, - * it'll temporarily get downgraded to the batchq) - */ -void -if_output(struct socket *so, struct mbuf *ifm) -{ - Slirp *slirp = ifm->slirp; - struct mbuf *ifq; - int on_fastq = 1; - - DEBUG_CALL("if_output"); - DEBUG_ARG("so = %p", so); - DEBUG_ARG("ifm = %p", ifm); - - /* - * First remove the mbuf from m_usedlist, - * since we're gonna use m_next and m_prev ourselves - * XXX Shouldn't need this, gotta change dtom() etc. - */ - if (ifm->m_flags & M_USEDLIST) { - remque(ifm); - ifm->m_flags &= ~M_USEDLIST; - } - - /* - * See if there's already a batchq list for this session. - * This can include an interactive session, which should go on fastq, - * but gets too greedy... hence it'll be downgraded from fastq to batchq. - * We mustn't put this packet back on the fastq (or we'll send it out of order) - * XXX add cache here? - */ - if (so) { - for (ifq = (struct mbuf *) slirp->if_batchq.qh_rlink; - (struct quehead *) ifq != &slirp->if_batchq; - ifq = ifq->ifq_prev) { - if (so == ifq->ifq_so) { - /* A match! */ - ifm->ifq_so = so; - ifs_insque(ifm, ifq->ifs_prev); - goto diddit; - } - } - } - - /* No match, check which queue to put it on */ - if (so && (so->so_iptos & IPTOS_LOWDELAY)) { - ifq = (struct mbuf *) slirp->if_fastq.qh_rlink; - on_fastq = 1; - /* - * Check if this packet is a part of the last - * packet's session - */ - if (ifq->ifq_so == so) { - ifm->ifq_so = so; - ifs_insque(ifm, ifq->ifs_prev); - goto diddit; - } - } else { - ifq = (struct mbuf *) slirp->if_batchq.qh_rlink; - } - - /* Create a new doubly linked list for this session */ - ifm->ifq_so = so; - ifs_init(ifm); - insque(ifm, ifq); - -diddit: - if (so) { - /* Update *_queued */ - so->so_queued++; - so->so_nqueued++; - /* - * Check if the interactive session should be downgraded to - * the batchq. A session is downgraded if it has queued 6 - * packets without pausing, and at least 3 of those packets - * have been sent over the link - * (XXX These are arbitrary numbers, probably not optimal..) - */ - if (on_fastq && ((so->so_nqueued >= 6) && - (so->so_nqueued - so->so_queued) >= 3)) { - - /* Remove from current queue... */ - remque(ifm->ifs_next); - - /* ...And insert in the new. That'll teach ya! */ - insque(ifm->ifs_next, &slirp->if_batchq); - } - } - - /* - * This prevents us from malloc()ing too many mbufs - */ - if_start(ifm->slirp); -} - -/* - * Send one packet from each session. - * If there are packets on the fastq, they are sent FIFO, before - * everything else. Then we choose the first packet from each - * batchq session (socket) and send it. - * For example, if there are 3 ftp sessions fighting for bandwidth, - * one packet will be sent from the first session, then one packet - * from the second session, then one packet from the third. - */ -void if_start(Slirp *slirp) -{ - uint64_t now = slirp->cb->clock_get_ns(slirp->opaque); - bool from_batchq = false; - struct mbuf *ifm, *ifm_next, *ifqt; - - DEBUG_CALL("if_start"); - - if (slirp->if_start_busy) { - return; - } - slirp->if_start_busy = true; - - struct mbuf *batch_head = NULL; - if (slirp->if_batchq.qh_link != &slirp->if_batchq) { - batch_head = (struct mbuf *) slirp->if_batchq.qh_link; - } - - if (slirp->if_fastq.qh_link != &slirp->if_fastq) { - ifm_next = (struct mbuf *) slirp->if_fastq.qh_link; - } else if (batch_head) { - /* Nothing on fastq, pick up from batchq */ - ifm_next = batch_head; - from_batchq = true; - } else { - ifm_next = NULL; - } - - while (ifm_next) { - ifm = ifm_next; - - ifm_next = ifm->ifq_next; - if ((struct quehead *) ifm_next == &slirp->if_fastq) { - /* No more packets in fastq, switch to batchq */ - ifm_next = batch_head; - from_batchq = true; - } - if ((struct quehead *) 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 or NDP resolution */ - continue; - } - - /* 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) { - 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; -} |