diff --git a/sys/dev/netmap/if_vtnet_netmap.h b/sys/dev/netmap/if_vtnet_netmap.h index f787bf573a28..cd652938bca5 100644 --- a/sys/dev/netmap/if_vtnet_netmap.h +++ b/sys/dev/netmap/if_vtnet_netmap.h @@ -1,447 +1,452 @@ /* * Copyright (C) 2014-2018 Vincenzo Maffione, Luigi Rizzo. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * $FreeBSD$ */ #include #include #include #include /* vtophys ? */ #include /* Register and unregister. */ static int vtnet_netmap_reg(struct netmap_adapter *na, int state) { struct ifnet *ifp = na->ifp; struct vtnet_softc *sc = ifp->if_softc; /* * Trigger a device reinit, asking vtnet_init_locked() to * also enter or exit netmap mode. */ VTNET_CORE_LOCK(sc); ifp->if_drv_flags &= ~IFF_DRV_RUNNING; vtnet_init_locked(sc, state ? VTNET_INIT_NETMAP_ENTER : VTNET_INIT_NETMAP_EXIT); VTNET_CORE_UNLOCK(sc); return (0); } /* Reconcile kernel and user view of the transmit ring. */ static int vtnet_netmap_txsync(struct netmap_kring *kring, int flags) { struct netmap_adapter *na = kring->na; struct ifnet *ifp = na->ifp; struct netmap_ring *ring = kring->ring; u_int ring_nr = kring->ring_id; u_int nm_i; /* index into the netmap ring */ u_int const lim = kring->nkr_num_slots - 1; u_int const head = kring->rhead; /* device-specific */ struct vtnet_softc *sc = ifp->if_softc; struct vtnet_txq *txq = &sc->vtnet_txqs[ring_nr]; struct virtqueue *vq = txq->vtntx_vq; int interrupts = !(kring->nr_kflags & NKR_NOINTR); u_int n; /* * First part: process new packets to send. */ nm_i = kring->nr_hwcur; if (nm_i != head) { /* we have new packets to send */ struct sglist *sg = txq->vtntx_sg; for (; nm_i != head; nm_i = nm_next(nm_i, lim)) { /* we use an empty header here */ struct netmap_slot *slot = &ring->slot[nm_i]; u_int len = slot->len; uint64_t paddr; void *addr = PNMB(na, slot, &paddr); int err; NM_CHECK_ADDR_LEN(na, addr, len); slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED); /* Initialize the scatterlist, expose it to the hypervisor, * and kick the hypervisor (if necessary). */ sglist_reset(sg); // cheap err = sglist_append(sg, &txq->vtntx_shrhdr, sc->vtnet_hdr_size); err |= sglist_append_phys(sg, paddr, len); KASSERT(err == 0, ("%s: cannot append to sglist %d", __func__, err)); err = virtqueue_enqueue(vq, /*cookie=*/txq, sg, /*readable=*/sg->sg_nseg, /*writeable=*/0); if (unlikely(err)) { if (err != ENOSPC) nm_prerr("virtqueue_enqueue(%s) failed: %d", kring->name, err); break; } } virtqueue_notify(vq); /* Update hwcur depending on where we stopped. */ kring->nr_hwcur = nm_i; /* note we migth break early */ } /* Free used slots. We only consider our own used buffers, recognized * by the token we passed to virtqueue_enqueue. */ n = 0; for (;;) { void *token = virtqueue_dequeue(vq, NULL); if (token == NULL) break; if (unlikely(token != (void *)txq)) nm_prerr("BUG: TX token mismatch"); else n++; } if (n > 0) { kring->nr_hwtail += n; if (kring->nr_hwtail > lim) kring->nr_hwtail -= lim + 1; } if (interrupts && virtqueue_nfree(vq) < 32) virtqueue_postpone_intr(vq, VQ_POSTPONE_LONG); return 0; } /* * Publish 'num 'netmap receive buffers to the host, starting * from the next available one (rx->vtnrx_nm_refill). * Return a positive error code on error, and 0 on success. * If we could not publish all of the buffers that's an error, * since the netmap ring and the virtqueue would go out of sync. */ static int vtnet_netmap_kring_refill(struct netmap_kring *kring, u_int num) { struct netmap_adapter *na = kring->na; struct ifnet *ifp = na->ifp; struct netmap_ring *ring = kring->ring; u_int ring_nr = kring->ring_id; u_int const lim = kring->nkr_num_slots - 1; u_int nm_i; /* device-specific */ struct vtnet_softc *sc = ifp->if_softc; struct vtnet_rxq *rxq = &sc->vtnet_rxqs[ring_nr]; struct virtqueue *vq = rxq->vtnrx_vq; /* use a local sglist, default might be short */ struct sglist_seg ss[2]; struct sglist sg = { ss, 0, 0, 2 }; for (nm_i = rxq->vtnrx_nm_refill; num > 0; nm_i = nm_next(nm_i, lim), num--) { struct netmap_slot *slot = &ring->slot[nm_i]; uint64_t paddr; void *addr = PNMB(na, slot, &paddr); int err; if (addr == NETMAP_BUF_BASE(na)) { /* bad buf */ if (netmap_ring_reinit(kring)) return EFAULT; } slot->flags &= ~NS_BUF_CHANGED; sglist_reset(&sg); err = sglist_append(&sg, &rxq->vtnrx_shrhdr, sc->vtnet_hdr_size); err |= sglist_append_phys(&sg, paddr, NETMAP_BUF_SIZE(na)); KASSERT(err == 0, ("%s: cannot append to sglist %d", __func__, err)); /* writable for the host */ err = virtqueue_enqueue(vq, /*cookie=*/rxq, &sg, /*readable=*/0, /*writeable=*/sg.sg_nseg); if (unlikely(err)) { nm_prerr("virtqueue_enqueue(%s) failed: %d", kring->name, err); break; } } rxq->vtnrx_nm_refill = nm_i; return num == 0 ? 0 : ENOSPC; } /* * Publish netmap buffers on a RX virtqueue. * Returns -1 if this virtqueue is not being opened in netmap mode. * If the virtqueue is being opened in netmap mode, return 0 on success and * a positive error code on failure. */ static int vtnet_netmap_rxq_populate(struct vtnet_rxq *rxq) { struct netmap_adapter *na = NA(rxq->vtnrx_sc->vtnet_ifp); struct netmap_kring *kring; struct netmap_slot *slot; int error; + int num; slot = netmap_reset(na, NR_RX, rxq->vtnrx_id, 0); if (slot == NULL) return -1; kring = na->rx_rings[rxq->vtnrx_id]; - /* Expose all the RX netmap buffers we can. In case of no indirect + /* + * Expose all the RX netmap buffers we can. In case of no indirect * buffers, the number of netmap slots in the RX ring matches the * maximum number of 2-elements sglist that the RX virtqueue can - * accommodate. We need to start from kring->nr_hwcur, which is 0 - * on netmap register and may be different from 0 if a virtio - * re-init happens while the device is in use by netmap. */ - rxq->vtnrx_nm_refill = kring->nr_hwcur; - error = vtnet_netmap_kring_refill(kring, na->num_rx_desc - 1); + * accommodate. We need to start from kring->nr_hwtail, which is 0 + * on the first netmap register and may be different from 0 if a + * virtio re-init (caused by a netma register or i.e., ifconfig) + * happens while the device is in use by netmap. + */ + rxq->vtnrx_nm_refill = kring->nr_hwtail; + num = na->num_rx_desc - 1 - nm_kr_rxspace(kring); + error = vtnet_netmap_kring_refill(kring, num); virtqueue_notify(rxq->vtnrx_vq); return error; } /* Reconcile kernel and user view of the receive ring. */ static int vtnet_netmap_rxsync(struct netmap_kring *kring, int flags) { struct netmap_adapter *na = kring->na; struct ifnet *ifp = na->ifp; struct netmap_ring *ring = kring->ring; u_int ring_nr = kring->ring_id; u_int nm_i; /* index into the netmap ring */ u_int const lim = kring->nkr_num_slots - 1; u_int const head = kring->rhead; int force_update = (flags & NAF_FORCE_READ) || (kring->nr_kflags & NKR_PENDINTR); int interrupts = !(kring->nr_kflags & NKR_NOINTR); /* device-specific */ struct vtnet_softc *sc = ifp->if_softc; struct vtnet_rxq *rxq = &sc->vtnet_rxqs[ring_nr]; struct virtqueue *vq = rxq->vtnrx_vq; /* * First part: import newly received packets. * Only accept our own buffers (matching the token). We should only get * matching buffers. The hwtail should never overrun hwcur, because - * we publish only N-1 receive buffers (and non N). + * we publish only N-1 receive buffers (and not N). * In any case we must not leave this routine with the interrupts * disabled, pending packets in the VQ and hwtail == (hwcur - 1), * otherwise the pending packets could stall. */ if (netmap_no_pendintr || force_update) { uint32_t hwtail_lim = nm_prev(kring->nr_hwcur, lim); void *token; vtnet_rxq_disable_intr(rxq); nm_i = kring->nr_hwtail; for (;;) { int len; token = virtqueue_dequeue(vq, &len); if (token == NULL) { /* * Enable the interrupts again and double-check * for more work. We can go on until we win the * race condition, since we are not replenishing * in the meanwhile, and thus we will process at * most N-1 slots. */ if (interrupts && vtnet_rxq_enable_intr(rxq)) { vtnet_rxq_disable_intr(rxq); continue; } break; } if (unlikely(token != (void *)rxq)) { nm_prerr("BUG: RX token mismatch"); } else { if (nm_i == hwtail_lim) { KASSERT(false, ("hwtail would " "overrun hwcur")); } /* Skip the virtio-net header. */ len -= sc->vtnet_hdr_size; if (unlikely(len < 0)) { nm_prlim(1, "Truncated virtio-net-header, " "missing %d bytes", -len); len = 0; } ring->slot[nm_i].len = len; ring->slot[nm_i].flags = 0; nm_i = nm_next(nm_i, lim); } } kring->nr_hwtail = nm_i; kring->nr_kflags &= ~NKR_PENDINTR; } /* * Second part: skip past packets that userspace has released. */ nm_i = kring->nr_hwcur; /* netmap ring index */ if (nm_i != head) { int released; int error; released = head - nm_i; if (released < 0) released += kring->nkr_num_slots; error = vtnet_netmap_kring_refill(kring, released); if (error) { nm_prerr("Failed to replenish RX VQ with %u sgs", released); return error; } kring->nr_hwcur = head; virtqueue_notify(vq); } nm_prdis("h %d c %d t %d hwcur %d hwtail %d", kring->rhead, kring->rcur, kring->rtail, kring->nr_hwcur, kring->nr_hwtail); return 0; } /* Enable/disable interrupts on all virtqueues. */ static void vtnet_netmap_intr(struct netmap_adapter *na, int state) { struct vtnet_softc *sc = na->ifp->if_softc; int i; for (i = 0; i < sc->vtnet_max_vq_pairs; i++) { struct vtnet_rxq *rxq = &sc->vtnet_rxqs[i]; struct vtnet_txq *txq = &sc->vtnet_txqs[i]; struct virtqueue *txvq = txq->vtntx_vq; if (state) { vtnet_rxq_enable_intr(rxq); virtqueue_enable_intr(txvq); } else { vtnet_rxq_disable_intr(rxq); virtqueue_disable_intr(txvq); } } } static int vtnet_netmap_tx_slots(struct vtnet_softc *sc) { int div; /* We need to prepend a virtio-net header to each netmap buffer to be * transmitted, therefore calling virtqueue_enqueue() passing sglist * with 2 elements. * TX virtqueues use indirect descriptors if the feature was negotiated * with the host, and if sc->vtnet_tx_nsegs > 1. With indirect * descriptors, a single virtio descriptor is sufficient to reference * each TX sglist. Without them, we need two separate virtio descriptors * for each TX sglist. We therefore compute the number of netmap TX * slots according to these assumptions. */ if ((sc->vtnet_flags & VTNET_FLAG_INDIRECT) && sc->vtnet_tx_nsegs > 1) div = 1; else div = 2; return virtqueue_size(sc->vtnet_txqs[0].vtntx_vq) / div; } static int vtnet_netmap_rx_slots(struct vtnet_softc *sc) { int div; /* We need to prepend a virtio-net header to each netmap buffer to be * received, therefore calling virtqueue_enqueue() passing sglist * with 2 elements. * RX virtqueues use indirect descriptors if the feature was negotiated * with the host, and if sc->vtnet_rx_nsegs > 1. With indirect * descriptors, a single virtio descriptor is sufficient to reference * each RX sglist. Without them, we need two separate virtio descriptors * for each RX sglist. We therefore compute the number of netmap RX * slots according to these assumptions. */ if ((sc->vtnet_flags & VTNET_FLAG_INDIRECT) && sc->vtnet_rx_nsegs > 1) div = 1; else div = 2; return virtqueue_size(sc->vtnet_rxqs[0].vtnrx_vq) / div; } static int vtnet_netmap_config(struct netmap_adapter *na, struct nm_config_info *info) { struct vtnet_softc *sc = na->ifp->if_softc; info->num_tx_rings = sc->vtnet_act_vq_pairs; info->num_rx_rings = sc->vtnet_act_vq_pairs; info->num_tx_descs = vtnet_netmap_tx_slots(sc); info->num_rx_descs = vtnet_netmap_rx_slots(sc); info->rx_buf_maxsize = NETMAP_BUF_SIZE(na); return 0; } static void vtnet_netmap_attach(struct vtnet_softc *sc) { struct netmap_adapter na; bzero(&na, sizeof(na)); na.ifp = sc->vtnet_ifp; na.na_flags = 0; na.num_tx_desc = vtnet_netmap_tx_slots(sc); na.num_rx_desc = vtnet_netmap_rx_slots(sc); na.num_tx_rings = na.num_rx_rings = sc->vtnet_max_vq_pairs; na.rx_buf_maxsize = 0; na.nm_register = vtnet_netmap_reg; na.nm_txsync = vtnet_netmap_txsync; na.nm_rxsync = vtnet_netmap_rxsync; na.nm_intr = vtnet_netmap_intr; na.nm_config = vtnet_netmap_config; netmap_attach(&na); nm_prinf("vtnet attached txq=%d, txd=%d rxq=%d, rxd=%d", na.num_tx_rings, na.num_tx_desc, na.num_tx_rings, na.num_rx_desc); } /* end of file */