On 30/11/18(Fri) 12:35, David Gwynne wrote:
> On Fri, Nov 30, 2018 at 12:21:11PM +1000, David Gwynne wrote:
> > i have a plan to allow virtual interfaces (eg, vlan, etherip, etc) to
> > provide their own output functions so they can bypass the ifq machinery
> > and push the packet onto the underlying layer directly.
> >
> > they'll still need to get an ethernet header though. vlan needs to get
> > the ethernet header and put the vlan shim into it, therefore
> > ether_resolve is exposed. etherip doesnt need a shim, it just wants
> > ethernet encapsulating the payload before adding its own headers to the
> > packet, therefore there is ether_encap.
> >
> > does this make sense?
> >
> > ok?
>
> this shows vlan and etherip using the new functions.
You're still using ifq_enqueue() and ifq_dequeue(). So, I'm not sure to
understand what is the gain of this change.
> Index: net/if_etherip.c
> ===================================================================
> RCS file: /cvs/src/sys/net/if_etherip.c,v
> retrieving revision 1.40
> diff -u -p -r1.40 if_etherip.c
> --- net/if_etherip.c 12 Nov 2018 23:57:06 -0000 1.40
> +++ net/if_etherip.c 30 Nov 2018 02:24:09 -0000
> @@ -102,7 +102,10 @@ void etheripattach(int);
> int etherip_clone_create(struct if_clone *, int);
> int etherip_clone_destroy(struct ifnet *);
> int etherip_ioctl(struct ifnet *, u_long, caddr_t);
> -void etherip_start(struct ifnet *);
> +int etherip_output(struct ifnet *, struct mbuf *, struct sockaddr *,
> + struct rtentry *rt);
> +void etherip_start(struct ifqueue *);
> +void etherip_send(struct ifnet *, struct mbuf *);
> int etherip_media_change(struct ifnet *);
> void etherip_media_status(struct ifnet *, struct ifmediareq *);
> int etherip_set_tunnel(struct etherip_softc *, struct if_laddrreq *);
> @@ -144,9 +147,10 @@ etherip_clone_create(struct if_clone *if
> ifp->if_softc = sc;
> ifp->if_hardmtu = ETHER_MAX_HARDMTU_LEN;
> ifp->if_ioctl = etherip_ioctl;
> - ifp->if_start = etherip_start;
> + ifp->if_output = etherip_output;
> + ifp->if_qstart = etherip_start;
> ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
> - ifp->if_xflags = IFXF_CLONED;
> + ifp->if_xflags = IFXF_MPSAFE | IFXF_CLONED;
> IFQ_SET_MAXLEN(&ifp->if_snd, IFQ_MAXLEN);
> ifp->if_capabilities = IFCAP_VLAN_MTU;
> ether_fakeaddr(ifp);
> @@ -201,40 +205,63 @@ etherip_media_status(struct ifnet *ifp,
> }
>
> void
> -etherip_start(struct ifnet *ifp)
> +etherip_send(struct ifnet *ifp, struct mbuf *m)
> {
> struct etherip_softc *sc = ifp->if_softc;
> - struct mbuf *m;
> int error;
> -#if NBPFILTER > 0
> - caddr_t if_bpf;
> -#endif
>
> - while ((m = ifq_dequeue(&ifp->if_snd)) != NULL) {
> #if NBPFILTER > 0
> - if_bpf = ifp->if_bpf;
> - if (if_bpf)
> - bpf_mtap_ether(if_bpf, m, BPF_DIRECTION_OUT);
> + caddr_t if_bpf = ifp->if_bpf;
> + if (if_bpf)
> + bpf_mtap_ether(if_bpf, m, BPF_DIRECTION_OUT);
> #endif
>
> - switch (sc->sc_tunnel.t_af) {
> - case AF_INET:
> - error = ip_etherip_output(ifp, m);
> - break;
> + switch (sc->sc_tunnel.t_af) {
> + case AF_INET:
> + error = ip_etherip_output(ifp, m);
> + break;
> #ifdef INET6
> - case AF_INET6:
> - error = ip6_etherip_output(ifp, m);
> - break;
> + case AF_INET6:
> + error = ip6_etherip_output(ifp, m);
> + break;
> #endif
> - default:
> - /* unhandled_af(sc->sc_tunnel.t_af); */
> - m_freem(m);
> - continue;
> - }
> + default:
> + /* unhandled_af(sc->sc_tunnel.t_af); */
> + m_freem(m);
> + error = ENETDOWN;
> + break;
> + }
>
> - if (error)
> - ifp->if_oerrors++;
> + if (error)
> + ifp->if_oerrors++;
> +}
> +
> +void
> +etherip_start(struct ifqueue *ifq)
> +{
> + struct ifnet *ifp = ifq->ifq_if;
> + struct mbuf *m;
> +
> + while ((m = ifq_dequeue(ifq)) != NULL)
> + etherip_send(ifp, m);
> +}
> +
> +int
> +etherip_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
> + struct rtentry *rt)
> +{
> + int error;
> +
> + m = ether_encap(ifp, m, dst, rt, &error);
> + if (m == NULL)
> + return (error);
> +
> + if (ifq_is_priq(&ifp->if_snd)) {
> + etherip_send(ifp, m);
> + return (0);
> }
> +
> + return (ifq_enqueue(&ifp->if_snd, m));
> }
>
> int
> Index: net/if_ethersubr.c
> ===================================================================
> RCS file: /cvs/src/sys/net/if_ethersubr.c,v
> retrieving revision 1.253
> diff -u -p -r1.253 if_ethersubr.c
> --- net/if_ethersubr.c 13 Mar 2018 01:31:48 -0000 1.253
> +++ net/if_ethersubr.c 30 Nov 2018 02:24:09 -0000
> @@ -483,7 +510,8 @@ ether_ifattach(struct ifnet *ifp)
> ifp->if_addrlen = ETHER_ADDR_LEN;
> ifp->if_hdrlen = ETHER_HDR_LEN;
> ifp->if_mtu = ETHERMTU;
> - ifp->if_output = ether_output;
> + if (ifp->if_output == NULL)
> + ifp->if_output = ether_output;
> ifp->if_rtrequest = ether_rtrequest;
>
> if_ih_insert(ifp, ether_input, NULL);
> Index: net/if_vlan.c
> ===================================================================
> RCS file: /cvs/src/sys/net/if_vlan.c,v
> retrieving revision 1.179
> diff -u -p -r1.179 if_vlan.c
> --- net/if_vlan.c 16 Nov 2018 08:43:08 -0000 1.179
> +++ net/if_vlan.c 30 Nov 2018 02:24:09 -0000
> @@ -58,6 +58,7 @@
> #include <sys/sockio.h>
> #include <sys/systm.h>
> #include <sys/rwlock.h>
> +#include <sys/percpu.h>
>
> #include <net/if.h>
> #include <net/if_dl.h>
> @@ -85,6 +86,8 @@ int vlan_clone_create(struct if_clone *,
> int vlan_clone_destroy(struct ifnet *);
>
> int vlan_input(struct ifnet *, struct mbuf *, void *);
> +int vlan_output(struct ifnet *, struct mbuf *, struct sockaddr *,
> + struct rtentry *rt);
> void vlan_start(struct ifqueue *ifq);
> int vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t addr);
>
> @@ -177,6 +180,7 @@ vlan_clone_create(struct if_clone *ifc,
>
> ifp->if_flags = IFF_BROADCAST | IFF_MULTICAST;
> ifp->if_xflags = IFXF_CLONED|IFXF_MPSAFE;
> + ifp->if_output = vlan_output;
> ifp->if_qstart = vlan_start;
> ifp->if_ioctl = vlan_ioctl;
> ifp->if_hardmtu = 0xffff;
> @@ -185,6 +189,8 @@ vlan_clone_create(struct if_clone *ifc,
> ether_ifattach(ifp);
> ifp->if_hdrlen = EVL_ENCAPLEN;
>
> + if_counters_alloc(ifp);
> +
> return (0);
> }
>
> @@ -239,6 +245,110 @@ vlan_mplstunnel(int ifidx)
> #endif
> }
>
> +static uint16_t
> +vlan_tag(const struct ifvlan *ifv, const struct mbuf *m)
> +{
> + int txprio = ifv->ifv_prio;
> + uint16_t prio;
> +
> + prio = (txprio == IF_HDRPRIO_PACKET) ?
> + m->m_pkthdr.pf.prio : txprio;
> +
> + /* IEEE 802.1p has prio 0 and 1 swapped */
> + if (prio <= 1)
> + prio = !prio;
> +
> + return (ifv->if_prio | (prio << EVL_PRIO_BITS));
> +}
> +
> +int
> +vlan_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
> + struct rtentry *rt)
> +{
> + struct ifvlan *ifv;
> + struct ifnet *ifp0;
> +#if NBPFILTER > 0
> + caddr_t if_bpf;
> +#endif
> + struct sockaddr vdst;
> + struct ether_header *eh = (struct ether_header *)vdst.sa_data;
> + int txprio;
> + uint16_t vtag;
> + int error;
> + unsigned int bytes;
> +
> + if (!ifq_is_priq(&ifp->if_snd)) {
> + /*
> + * user wants to delay packets, which relies on the ifq
> + * machinery. fall back to if_enqueue via ether_output.
> + */
> + return (ether_output(ifp, m, dst, rt));
> + }
> +
> + error = ether_resolve(ifp, m, dst, rt, eh);
> + switch (error) {
> + case 0:
> + break;
> + case EAGAIN:
> + return (0);
> + default:
> + return (error);
> + }
> +
> + ifv = ifp->if_softc;
> + ifp0 = if_get(ifv->ifv_ifp0);
> + if (ifp0 == NULL || !ISSET(ifp0->if_flags, IFF_RUNNING)) {
> + m_freem(m);
> + error = ENETDOWN;
> + goto leave;
> + }
> +
> +#if NBPFILTER > 0
> + if_bpf = ifp->if_bpf;
> + if (if_bpf) {
> + bpf_mtap_hdr(if_bpf, (caddr_t)eh, sizeof(*eh), m,
> + BPF_DIRECTION_OUT, NULL);
> + }
> +#endif
> +
> + vtag = vlan_tag(ifv, m);
> +
> + bytes = sizeof(*eh) + m->m_pkthdr.len; /* plus shim? */
> +
> + /*
> + * If the underlying interface cannot do VLAN tag insertion
> + * itself, create an encapsulation header.
> + */
> + if (ISSET(ifp0->if_capabilities, IFCAP_VLAN_HWTAGGING) &&
> + ifv->ifv_type == ETHERTYPE_VLAN) {
> + m->m_pkthdr.ether_vtag = vtag;
> + m->m_flags |= M_VLANTAG;
> + } else {
> + struct ether_vlan_shim *evl;
> +
> + M_PREPEND(m, sizeof(*evl), M_DONTWAIT);
> + if (m == NULL) {
> + error = ENOBUFS;
> + goto leave;
> + }
> +
> + evl = mtod(m, struct ether_vlan_shim *);
> + evl->evl_tag = htons(vtag);
> + evl->evl_proto = eh->ether_type;
> +
> + eh->ether_type = htons(ifv->ifv_type);
> + }
> +
> + counters_pkt(ifp->if_counters, ifc_opackets, ifc_obytes, bytes);
> +
> + vdst.sa_family = pseudo_AF_HDRCMPLT;
> + error = ifp0->if_output(ifp0, m, &vdst, NULL);
> +
> +leave:
> + if_put(ifp0);
> + return (error);
> +}
> +
> void
> vlan_start(struct ifqueue *ifq)
> {
> @@ -246,31 +356,22 @@ vlan_start(struct ifqueue *ifq)
> struct ifvlan *ifv;
> struct ifnet *ifp0;
> struct mbuf *m;
> - int txprio;
> - uint8_t prio;
> + uint16_t vtag;
>
> ifv = ifp->if_softc;
> ifp0 = if_get(ifv->ifv_ifp0);
> - if (ifp0 == NULL || (ifp0->if_flags & (IFF_UP|IFF_RUNNING)) !=
> - (IFF_UP|IFF_RUNNING)) {
> + if (ifp0 == NULL || !ISSET(ifp0->if_flags, IFF_RUNNING)) {
> ifq_purge(ifq);
> goto leave;
> }
>
> - txprio = ifv->ifv_prio;
> -
> while ((m = ifq_dequeue(ifq)) != NULL) {
> #if NBPFILTER > 0
> if (ifp->if_bpf)
> bpf_mtap_ether(ifp->if_bpf, m, BPF_DIRECTION_OUT);
> #endif /* NBPFILTER > 0 */
>
> - prio = (txprio == IF_HDRPRIO_PACKET) ?
> - m->m_pkthdr.pf.prio : txprio;
> -
> - /* IEEE 802.1p has prio 0 and 1 swapped */
> - if (prio <= 1)
> - prio = !prio;
> + vtag = vlan_tag(ifv, m);
>
> /*
> * If this packet came from a pseudowire it means it already
> @@ -285,23 +386,17 @@ vlan_start(struct ifqueue *ifq)
> */
> } else if ((ifp0->if_capabilities & IFCAP_VLAN_HWTAGGING) &&
> (ifv->ifv_type == ETHERTYPE_VLAN)) {
> - m->m_pkthdr.ether_vtag = ifv->ifv_tag +
> - (prio << EVL_PRIO_BITS);
> + m->m_pkthdr.ether_vtag = vtag;
> m->m_flags |= M_VLANTAG;
> } else {
> - m = vlan_inject(m, ifv->ifv_type, ifv->ifv_tag |
> - (prio << EVL_PRIO_BITS));
> + m = vlan_inject(m, ifv->ifv_type, vtag);
> if (m == NULL) {
> - ifp->if_oerrors++;
> + ifq->ifq_oerrors++;
> continue;
> }
> }
>
> - if (if_enqueue(ifp0, m)) {
> - ifp->if_oerrors++;
> - ifq->ifq_errors++;
> - continue;
> - }
> + if_enqueue(ifp0, m);
> }
>
> leave:
> Index: net/ifq.h
> ===================================================================
> RCS file: /cvs/src/sys/net/ifq.h,v
> retrieving revision 1.20
> diff -u -p -r1.20 ifq.h
> --- net/ifq.h 4 Jan 2018 11:02:57 -0000 1.20
> +++ net/ifq.h 30 Nov 2018 02:24:09 -0000
> @@ -421,6 +422,7 @@ void ifq_barrier(struct ifqueue *);
> #define ifq_len(_ifq) ((_ifq)->ifq_len)
> #define ifq_empty(_ifq) (ifq_len(_ifq) == 0)
> #define ifq_set_maxlen(_ifq, _l) ((_ifq)->ifq_maxlen = (_l))
> +#define ifq_is_priq(_ifq) ((_ifq)->ifq_ops ==
> ifq_priq_ops)
>
> static inline void
> ifq_set_oactive(struct ifqueue *ifq)
> Index: netinet/if_ether.h
> ===================================================================
> RCS file: /cvs/src/sys/netinet/if_ether.h,v
> retrieving revision 1.73
> diff -u -p -r1.73 if_ether.h
> --- netinet/if_ether.h 29 Nov 2016 10:09:57 -0000 1.73
> +++ netinet/if_ether.h 30 Nov 2018 02:24:09 -0000
> @@ -92,6 +92,11 @@ struct ether_vlan_header {
> u_int16_t evl_proto;
> };
>
> +struct ether_vlan_shim {
> + u_int16_t evl_tag;
> + u_int16_t evl_proto;
> +};
> +
> #define EVL_VLID_MASK 0xFFF
> #define EVL_VLID_NULL 0x000
> /* 0x000 and 0xfff are reserved */
> Index: net/if_var.h
> ===================================================================
> RCS file: /cvs/src/sys/net/if_var.h,v
> retrieving revision 1.90
> diff -u -p -r1.90 if_var.h
> --- net/if_var.h 10 Sep 2018 16:18:34 -0000 1.90
> +++ net/if_var.h 30 Nov 2018 02:24:09 -0000
> @@ -76,6 +76,7 @@
> struct rtentry;
> struct ifnet;
> struct task;
> +struct cpumem;
>
> /*
> * Structure describing a `cloning' interface.
> @@ -144,6 +145,7 @@ struct ifnet { /* and the
> entries */
> unsigned short if_flags; /* [N] up/down, broadcast, etc. */
> int if_xflags; /* [N] extra softnet flags */
> struct if_data if_data; /* stats and other data about if */
> + struct cpumem *if_counters; /* per cpu stats */
> uint32_t if_hardmtu; /* [d] maximum MTU device supports */
> char if_description[IFDESCRSIZE]; /* [c] interface description */
> u_short if_rtlabelid; /* [c] next route label */
> @@ -202,6 +204,23 @@ struct ifnet { /* and the
> entries */
> #define if_capabilities if_data.ifi_capabilities
> #define if_rdomain if_data.ifi_rdomain
>
> +enum if_counters {
> + ifc_ipackets, /* packets received on interface */
> + ifc_ierrors, /* input errors on interface */
> + ifc_opackets, /* packets sent on interface */
> + ifc_oerrors, /* output errors on interface */
> + ifc_collisions, /* collisions on csma interfaces */
> + ifc_ibytes, /* total number of octets received */
> + ifc_obytes, /* total number of octets sent */
> + ifc_imcasts, /* packets received via multicast */
> + ifc_omcasts, /* packets sent via multicast */
> + ifc_iqdrops, /* dropped on input, this interface */
> + ifc_oqdrops, /* dropped on output, this interface */
> + ifc_noproto, /* destined for unsupported protocol */
> +
> + ifc_ncounters
> +};
> +
> /*
> * The ifaddr structure contains information about one address
> * of an interface. They are maintained by the different address families,
> @@ -356,6 +375,9 @@ u_int if_rxr_get(struct if_rxring *, u_i
> int if_rxr_info_ioctl(struct if_rxrinfo *, u_int, struct if_rxring_info *);
> int if_rxr_ioctl(struct if_rxrinfo *, const char *, u_int,
> struct if_rxring *);
> +
> +void if_counters_alloc(struct ifnet *);
> +void if_counters_free(struct ifnet *);
>
> #endif /* _KERNEL */
>
> Index: net/if.c
> ===================================================================
> RCS file: /cvs/src/sys/net/if.c,v
> retrieving revision 1.568
> diff -u -p -r1.568 if.c
> --- net/if.c 29 Nov 2018 00:11:49 -0000 1.568
> +++ net/if.c 30 Nov 2018 02:24:09 -0000
> @@ -84,6 +84,7 @@
> #include <sys/domain.h>
> #include <sys/task.h>
> #include <sys/atomic.h>
> +#include <sys/percpu.h>
> #include <sys/proc.h>
>
> #include <dev/rndvar.h>
> @@ -1103,6 +1104,9 @@ if_detach(struct ifnet *ifp)
> splx(s);
> NET_UNLOCK();
>
> + if (ifp->if_counters != NULL)
> + if_counters_free(ifp);
> +
> for (i = 0; i < ifp->if_nifqs; i++)
> ifq_destroy(ifp->if_ifqs[i]);
> if (ifp->if_ifqs != ifp->if_snd.ifq_ifqs) {
> @@ -2362,11 +2366,47 @@ ifconf(caddr_t data)
> }
>
> void
> +if_counters_alloc(struct ifnet *ifp)
> +{
> + KASSERT(ifp->if_counters == NULL);
> +
> + ifp->if_counters = counters_alloc(ifc_ncounters);
> +}
> +
> +void
> +if_counters_free(struct ifnet *ifp)
> +{
> + KASSERT(ifp->if_counters != NULL);
> +
> + counters_free(ifp->if_counters, ifc_ncounters);
> + ifp->if_counters = NULL;
> +}
> +
> +void
> if_getdata(struct ifnet *ifp, struct if_data *data)
> {
> unsigned int i;
>
> *data = ifp->if_data;
> +
> + if (ifp->if_counters != NULL) {
> + uint64_t counters[ifc_ncounters];
> +
> + counters_read(ifp->if_counters, counters, nitems(counters));
> +
> + data->ifi_ipackets += counters[ifc_ipackets];
> + data->ifi_ierrors += counters[ifc_ierrors];
> + data->ifi_opackets += counters[ifc_opackets];
> + data->ifi_oerrors += counters[ifc_oerrors];
> + data->ifi_collisions += counters[ifc_collisions];
> + data->ifi_ibytes += counters[ifc_ibytes];
> + data->ifi_obytes += counters[ifc_obytes];
> + data->ifi_imcasts += counters[ifc_imcasts];
> + data->ifi_omcasts += counters[ifc_omcasts];
> + data->ifi_iqdrops += counters[ifc_iqdrops];
> + data->ifi_oqdrops += counters[ifc_oqdrops];
> + data->ifi_noproto += counters[ifc_noproto];
> + }
>
> for (i = 0; i < ifp->if_nifqs; i++) {
> struct ifqueue *ifq = ifp->if_ifqs[i];
>
