/*      $OpenBSD: if_trunk.c,v 1.30 2007/01/31 06:20:19 reyk Exp $      */

/*
 * Copyright (c) 2005, 2006 Reyk Floeter <reyk@openbsd.org>
 * Copyright (c) 2007 Andrew Thompson <thompsa@FreeBSD.org>
 * Copyright (c) 2014, 2016 Marcelo Araujo <araujo@FreeBSD.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_kern_tls.h"
#include "opt_ratelimit.h"

#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/module.h>
#include <sys/priv.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/lock.h>
#include <sys/rmlock.h>
#include <sys/sx.h>
#include <sys/taskqueue.h>
#include <sys/eventhandler.h>

#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_clone.h>
#include <net/if_arp.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>
#include <net/if_var.h>
#include <net/if_private.h>
#include <net/bpf.h>
#include <net/route.h>
#include <net/vnet.h>
#include <net/infiniband.h>

#if defined(INET) || defined(INET6)
#include <netinet/in.h>
#include <netinet/ip.h>
#endif
#ifdef INET
#include <netinet/in_systm.h>
#include <netinet/if_ether.h>
#endif

#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/in6_var.h>
#include <netinet6/in6_ifattach.h>
#endif

#include <net/if_vlan_var.h>
#include <net/if_lagg.h>
#include <net/ieee8023ad_lacp.h>

#ifdef DEV_NETMAP
MODULE_DEPEND(if_lagg, netmap, 1, 1, 1);
#endif

#define LAGG_SX_INIT(_sc)       sx_init(&(_sc)->sc_sx, "if_lagg sx")
#define LAGG_SX_DESTROY(_sc)    sx_destroy(&(_sc)->sc_sx)
#define LAGG_XLOCK(_sc)         sx_xlock(&(_sc)->sc_sx)
#define LAGG_XUNLOCK(_sc)       sx_xunlock(&(_sc)->sc_sx)
#define LAGG_XLOCK_ASSERT(_sc)  sx_assert(&(_sc)->sc_sx, SA_XLOCKED)
#define LAGG_SLOCK(_sc)         sx_slock(&(_sc)->sc_sx)
#define LAGG_SUNLOCK(_sc)       sx_sunlock(&(_sc)->sc_sx)
#define LAGG_SXLOCK_ASSERT(_sc) sx_assert(&(_sc)->sc_sx, SA_LOCKED)

/* Special flags we should propagate to the lagg ports. */
static struct {
        int flag;
        int (*func)(struct ifnet *, int);
} lagg_pflags[] = {
        {IFF_PROMISC, ifpromisc},
        {IFF_ALLMULTI, if_allmulti},
        {0, NULL}
};

struct lagg_snd_tag {
        struct m_snd_tag com;
        struct m_snd_tag *tag;
};

VNET_DEFINE_STATIC(SLIST_HEAD(__trhead, lagg_softc), lagg_list) =
    SLIST_HEAD_INITIALIZER(); /* list of laggs */
#define V_lagg_list     VNET(lagg_list)
VNET_DEFINE_STATIC(struct mtx, lagg_list_mtx);
#define V_lagg_list_mtx VNET(lagg_list_mtx)
#define LAGG_LIST_LOCK_INIT(x)          mtx_init(&V_lagg_list_mtx, \
                                        "if_lagg list", NULL, MTX_DEF)
#define LAGG_LIST_LOCK_DESTROY(x)       mtx_destroy(&V_lagg_list_mtx)
#define LAGG_LIST_LOCK(x)               mtx_lock(&V_lagg_list_mtx)
#define LAGG_LIST_UNLOCK(x)             mtx_unlock(&V_lagg_list_mtx)
static eventhandler_tag lagg_detach_cookie = NULL;

static int      lagg_clone_create(struct if_clone *, char *, size_t,
                    struct ifc_data *, struct ifnet **);
static int      lagg_clone_destroy(struct if_clone *, struct ifnet *, uint32_t);
VNET_DEFINE_STATIC(struct if_clone *, lagg_cloner);
#define V_lagg_cloner   VNET(lagg_cloner)
static const char laggname[] = "lagg";
static MALLOC_DEFINE(M_LAGG, laggname, "802.3AD Link Aggregation Interface");

static void     lagg_capabilities(struct lagg_softc *);
static int      lagg_port_create(struct lagg_softc *, struct ifnet *);
static int      lagg_port_destroy(struct lagg_port *, int);
static struct mbuf *lagg_input_ethernet(struct ifnet *, struct mbuf *);
static struct mbuf *lagg_input_infiniband(struct ifnet *, struct mbuf *);
static void     lagg_linkstate(struct lagg_softc *);
static void     lagg_port_state(struct ifnet *, int);
static int      lagg_port_ioctl(struct ifnet *, u_long, caddr_t);
static int      lagg_port_output(struct ifnet *, struct mbuf *,
                    const struct sockaddr *, struct route *);
static void     lagg_port_ifdetach(void *arg __unused, struct ifnet *);
#ifdef LAGG_PORT_STACKING
static int      lagg_port_checkstacking(struct lagg_softc *);
#endif
static void     lagg_port2req(struct lagg_port *, struct lagg_reqport *);
static void     lagg_if_updown(struct lagg_softc *, bool);
static void     lagg_init(void *);
static void     lagg_init_locked(struct lagg_softc *);
static void     lagg_stop(struct lagg_softc *);
static int      lagg_ioctl(struct ifnet *, u_long, caddr_t);
#if defined(KERN_TLS) || defined(RATELIMIT)
static int      lagg_snd_tag_alloc(struct ifnet *,
                    union if_snd_tag_alloc_params *,
                    struct m_snd_tag **);
static int      lagg_snd_tag_modify(struct m_snd_tag *,
                    union if_snd_tag_modify_params *);
static int      lagg_snd_tag_query(struct m_snd_tag *,
                    union if_snd_tag_query_params *);
static void     lagg_snd_tag_free(struct m_snd_tag *);
static struct m_snd_tag *lagg_next_snd_tag(struct m_snd_tag *);
static void     lagg_ratelimit_query(struct ifnet *,
                    struct if_ratelimit_query_results *);
#endif
static int      lagg_setmulti(struct lagg_port *);
static int      lagg_clrmulti(struct lagg_port *);
static void     lagg_setcaps(struct lagg_port *, int cap, int cap2);
static int      lagg_setflag(struct lagg_port *, int, int,
                    int (*func)(struct ifnet *, int));
static int      lagg_setflags(struct lagg_port *, int status);
static uint64_t lagg_get_counter(struct ifnet *ifp, ift_counter cnt);
static int      lagg_transmit_ethernet(struct ifnet *, struct mbuf *);
static int      lagg_transmit_infiniband(struct ifnet *, struct mbuf *);
static void     lagg_qflush(struct ifnet *);
static int      lagg_media_change(struct ifnet *);
static void     lagg_media_status(struct ifnet *, struct ifmediareq *);
static struct lagg_port *lagg_link_active(struct lagg_softc *,
                    struct lagg_port *);

/* No proto */
static int      lagg_none_start(struct lagg_softc *, struct mbuf *);
static struct mbuf *lagg_none_input(struct lagg_softc *, struct lagg_port *,
                    struct mbuf *);

/* Simple round robin */
static void     lagg_rr_attach(struct lagg_softc *);
static int      lagg_rr_start(struct lagg_softc *, struct mbuf *);

/* Active failover */
static int      lagg_fail_start(struct lagg_softc *, struct mbuf *);
static struct mbuf *lagg_fail_input(struct lagg_softc *, struct lagg_port *,
                    struct mbuf *);

/* Loadbalancing */
static void     lagg_lb_attach(struct lagg_softc *);
static void     lagg_lb_detach(struct lagg_softc *);
static int      lagg_lb_port_create(struct lagg_port *);
static void     lagg_lb_port_destroy(struct lagg_port *);
static int      lagg_lb_start(struct lagg_softc *, struct mbuf *);
static int      lagg_lb_porttable(struct lagg_softc *, struct lagg_port *);

/* Broadcast */
static int      lagg_bcast_start(struct lagg_softc *, struct mbuf *);

/* 802.3ad LACP */
static void     lagg_lacp_attach(struct lagg_softc *);
static void     lagg_lacp_detach(struct lagg_softc *);
static int      lagg_lacp_start(struct lagg_softc *, struct mbuf *);
static struct mbuf *lagg_lacp_input(struct lagg_softc *, struct lagg_port *,
                    struct mbuf *);
static void     lagg_lacp_lladdr(struct lagg_softc *);

/* Default input */
static struct mbuf *lagg_default_input(struct lagg_softc *, struct lagg_port *,
                    struct mbuf *);

/* lagg protocol table */
static const struct lagg_proto {
        void            (*pr_attach)(struct lagg_softc *);
        void            (*pr_detach)(struct lagg_softc *);
        int             (*pr_start)(struct lagg_softc *, struct mbuf *);
        struct mbuf *   (*pr_input)(struct lagg_softc *, struct lagg_port *,
                            struct mbuf *);
        int             (*pr_addport)(struct lagg_port *);
        void            (*pr_delport)(struct lagg_port *);
        void            (*pr_linkstate)(struct lagg_port *);
        void            (*pr_init)(struct lagg_softc *);
        void            (*pr_stop)(struct lagg_softc *);
        void            (*pr_lladdr)(struct lagg_softc *);
        void            (*pr_request)(struct lagg_softc *, void *);
        void            (*pr_portreq)(struct lagg_port *, void *);
} lagg_protos[] = {
    [LAGG_PROTO_NONE] = {
        .pr_start = lagg_none_start,
        .pr_input = lagg_none_input,
    },
    [LAGG_PROTO_ROUNDROBIN] = {
        .pr_attach = lagg_rr_attach,
        .pr_start = lagg_rr_start,
        .pr_input = lagg_default_input,
    },
    [LAGG_PROTO_FAILOVER] = {
        .pr_start = lagg_fail_start,
        .pr_input = lagg_fail_input,
    },
    [LAGG_PROTO_LOADBALANCE] = {
        .pr_attach = lagg_lb_attach,
        .pr_detach = lagg_lb_detach,
        .pr_start = lagg_lb_start,
        .pr_input = lagg_default_input,
        .pr_addport = lagg_lb_port_create,
        .pr_delport = lagg_lb_port_destroy,
    },
    [LAGG_PROTO_LACP] = {
        .pr_attach = lagg_lacp_attach,
        .pr_detach = lagg_lacp_detach,
        .pr_start = lagg_lacp_start,
        .pr_input = lagg_lacp_input,
        .pr_addport = lacp_port_create,
        .pr_delport = lacp_port_destroy,
        .pr_linkstate = lacp_linkstate,
        .pr_init = lacp_init,
        .pr_stop = lacp_stop,
        .pr_lladdr = lagg_lacp_lladdr,
        .pr_request = lacp_req,
        .pr_portreq = lacp_portreq,
    },
    [LAGG_PROTO_BROADCAST] = {
        .pr_start = lagg_bcast_start,
        .pr_input = lagg_default_input,
    },
};

SYSCTL_DECL(_net_link);
SYSCTL_NODE(_net_link, OID_AUTO, lagg, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
    "Link Aggregation");

/* Allow input on any failover links */
VNET_DEFINE_STATIC(int, lagg_failover_rx_all);
#define V_lagg_failover_rx_all  VNET(lagg_failover_rx_all)
SYSCTL_INT(_net_link_lagg, OID_AUTO, failover_rx_all, CTLFLAG_RW | CTLFLAG_VNET,
    &VNET_NAME(lagg_failover_rx_all), 0,
    "Accept input from any interface in a failover lagg");

/* Default value for using flowid */
VNET_DEFINE_STATIC(int, def_use_flowid) = 0;
#define V_def_use_flowid        VNET(def_use_flowid)
SYSCTL_INT(_net_link_lagg, OID_AUTO, default_use_flowid,
    CTLFLAG_RWTUN | CTLFLAG_VNET, &VNET_NAME(def_use_flowid), 0,
    "Default setting for using flow id for load sharing");

/* Default value for using numa */
VNET_DEFINE_STATIC(int, def_use_numa) = 1;
#define V_def_use_numa  VNET(def_use_numa)
SYSCTL_INT(_net_link_lagg, OID_AUTO, default_use_numa,
    CTLFLAG_RWTUN | CTLFLAG_VNET, &VNET_NAME(def_use_numa), 0,
    "Use numa to steer flows");

/* Default value for flowid shift */
VNET_DEFINE_STATIC(int, def_flowid_shift) = 16;
#define V_def_flowid_shift      VNET(def_flowid_shift)
SYSCTL_INT(_net_link_lagg, OID_AUTO, default_flowid_shift,
    CTLFLAG_RWTUN | CTLFLAG_VNET, &VNET_NAME(def_flowid_shift), 0,
    "Default setting for flowid shift for load sharing");

static void
vnet_lagg_init(const void *unused __unused)
{

        LAGG_LIST_LOCK_INIT();
        struct if_clone_addreq req = {
                .create_f = lagg_clone_create,
                .destroy_f = lagg_clone_destroy,
                .flags = IFC_F_AUTOUNIT,
        };
        V_lagg_cloner = ifc_attach_cloner(laggname, &req);
}
VNET_SYSINIT(vnet_lagg_init, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY,
    vnet_lagg_init, NULL);

static void
vnet_lagg_uninit(const void *unused __unused)
{

        ifc_detach_cloner(V_lagg_cloner);
        LAGG_LIST_LOCK_DESTROY();
}
VNET_SYSUNINIT(vnet_lagg_uninit, SI_SUB_INIT_IF, SI_ORDER_ANY,
    vnet_lagg_uninit, NULL);

static int
lagg_modevent(module_t mod, int type, void *data)
{

        switch (type) {
        case MOD_LOAD:
                lagg_input_ethernet_p = lagg_input_ethernet;
                lagg_input_infiniband_p = lagg_input_infiniband;
                lagg_linkstate_p = lagg_port_state;
                lagg_detach_cookie = EVENTHANDLER_REGISTER(
                    ifnet_departure_event, lagg_port_ifdetach, NULL,
                    EVENTHANDLER_PRI_ANY);
                break;
        case MOD_UNLOAD:
                EVENTHANDLER_DEREGISTER(ifnet_departure_event,
                    lagg_detach_cookie);
                lagg_input_ethernet_p = NULL;
                lagg_input_infiniband_p = NULL;
                lagg_linkstate_p = NULL;
                break;
        default:
                return (EOPNOTSUPP);
        }
        return (0);
}

static moduledata_t lagg_mod = {
        "if_lagg",
        lagg_modevent,
        0
};

DECLARE_MODULE(if_lagg, lagg_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
MODULE_VERSION(if_lagg, 1);
MODULE_DEPEND(if_lagg, if_infiniband, 1, 1, 1);

static void
lagg_proto_attach(struct lagg_softc *sc, lagg_proto pr)
{

        LAGG_XLOCK_ASSERT(sc);
        KASSERT(sc->sc_proto == LAGG_PROTO_NONE, ("%s: sc %p has proto",
            __func__, sc));

        if (sc->sc_ifflags & IFF_DEBUG)
                if_printf(sc->sc_ifp, "using proto %u\n", pr);

        if (lagg_protos[pr].pr_attach != NULL)
                lagg_protos[pr].pr_attach(sc);
        sc->sc_proto = pr;
}

static void
lagg_proto_detach(struct lagg_softc *sc)
{
        lagg_proto pr;

        LAGG_XLOCK_ASSERT(sc);
        pr = sc->sc_proto;
        sc->sc_proto = LAGG_PROTO_NONE;

        if (lagg_protos[pr].pr_detach != NULL)
                lagg_protos[pr].pr_detach(sc);
}

static inline int
lagg_proto_start(struct lagg_softc *sc, struct mbuf *m)
{

        return (lagg_protos[sc->sc_proto].pr_start(sc, m));
}

static inline struct mbuf *
lagg_proto_input(struct lagg_softc *sc, struct lagg_port *lp, struct mbuf *m)
{

        return (lagg_protos[sc->sc_proto].pr_input(sc, lp, m));
}

static int
lagg_proto_addport(struct lagg_softc *sc, struct lagg_port *lp)
{

        if (lagg_protos[sc->sc_proto].pr_addport == NULL)
                return (0);
        else
                return (lagg_protos[sc->sc_proto].pr_addport(lp));
}

static void
lagg_proto_delport(struct lagg_softc *sc, struct lagg_port *lp)
{

        if (lagg_protos[sc->sc_proto].pr_delport != NULL)
                lagg_protos[sc->sc_proto].pr_delport(lp);
}

static void
lagg_proto_linkstate(struct lagg_softc *sc, struct lagg_port *lp)
{

        if (lagg_protos[sc->sc_proto].pr_linkstate != NULL)
                lagg_protos[sc->sc_proto].pr_linkstate(lp);
}

static void
lagg_proto_init(struct lagg_softc *sc)
{

        if (lagg_protos[sc->sc_proto].pr_init != NULL)
                lagg_protos[sc->sc_proto].pr_init(sc);
}

static void
lagg_proto_stop(struct lagg_softc *sc)
{

        if (lagg_protos[sc->sc_proto].pr_stop != NULL)
                lagg_protos[sc->sc_proto].pr_stop(sc);
}

static void
lagg_proto_lladdr(struct lagg_softc *sc)
{

        if (lagg_protos[sc->sc_proto].pr_lladdr != NULL)
                lagg_protos[sc->sc_proto].pr_lladdr(sc);
}

static void
lagg_proto_request(struct lagg_softc *sc, void *v)
{

        if (lagg_protos[sc->sc_proto].pr_request != NULL)
                lagg_protos[sc->sc_proto].pr_request(sc, v);
}

static void
lagg_proto_portreq(struct lagg_softc *sc, struct lagg_port *lp, void *v)
{

        if (lagg_protos[sc->sc_proto].pr_portreq != NULL)
                lagg_protos[sc->sc_proto].pr_portreq(lp, v);
}

/*
 * This routine is run via an vlan
 * config EVENT
 */
static void
lagg_register_vlan(void *arg, struct ifnet *ifp, u_int16_t vtag)
{
        struct lagg_softc *sc = ifp->if_softc;
        struct lagg_port *lp;

        if (ifp->if_softc != arg) /* Not our event */
                return;

        LAGG_XLOCK(sc);
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries)
                EVENTHANDLER_INVOKE(vlan_config, lp->lp_ifp, vtag);
        LAGG_XUNLOCK(sc);
}

/*
 * This routine is run via an vlan
 * unconfig EVENT
 */
static void
lagg_unregister_vlan(void *arg, struct ifnet *ifp, u_int16_t vtag)
{
        struct lagg_softc *sc = ifp->if_softc;
        struct lagg_port *lp;

        if (ifp->if_softc != arg) /* Not our event */
                return;

        LAGG_XLOCK(sc);
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries)
                EVENTHANDLER_INVOKE(vlan_unconfig, lp->lp_ifp, vtag);
        LAGG_XUNLOCK(sc);
}

static int
lagg_clone_create(struct if_clone *ifc, char *name, size_t len,
    struct ifc_data *ifd, struct ifnet **ifpp)
{
        struct iflaggparam iflp;
        struct lagg_softc *sc;
        struct ifnet *ifp;
        int if_type;
        int error;
        static const uint8_t eaddr[LAGG_ADDR_LEN];

        if (ifd->params != NULL) {
                error = ifc_copyin(ifd, &iflp, sizeof(iflp));
                if (error)
                        return (error);

                switch (iflp.lagg_type) {
                case LAGG_TYPE_ETHERNET:
                        if_type = IFT_ETHER;
                        break;
                case LAGG_TYPE_INFINIBAND:
                        if_type = IFT_INFINIBAND;
                        break;
                default:
                        return (EINVAL);
                }
        } else {
                if_type = IFT_ETHER;
        }

        sc = malloc(sizeof(*sc), M_LAGG, M_WAITOK | M_ZERO);
        ifp = sc->sc_ifp = if_alloc(if_type);
        LAGG_SX_INIT(sc);

        mtx_init(&sc->sc_mtx, "lagg-mtx", NULL, MTX_DEF);
        callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);

        LAGG_XLOCK(sc);
        if (V_def_use_flowid)
                sc->sc_opts |= LAGG_OPT_USE_FLOWID;
        if (V_def_use_numa)
                sc->sc_opts |= LAGG_OPT_USE_NUMA;
        sc->flowid_shift = V_def_flowid_shift;

        /* Hash all layers by default */
        sc->sc_flags = MBUF_HASHFLAG_L2 | MBUF_HASHFLAG_L3 | MBUF_HASHFLAG_L4;

        lagg_proto_attach(sc, LAGG_PROTO_DEFAULT);

        CK_SLIST_INIT(&sc->sc_ports);

        switch (if_type) {
        case IFT_ETHER:
                /* Initialise pseudo media types */
                ifmedia_init(&sc->sc_media, 0, lagg_media_change,
                    lagg_media_status);
                ifmedia_add(&sc->sc_media, IFM_ETHER | IFM_AUTO, 0, NULL);
                ifmedia_set(&sc->sc_media, IFM_ETHER | IFM_AUTO);

                if_initname(ifp, laggname, ifd->unit);
                ifp->if_transmit = lagg_transmit_ethernet;
                break;
        case IFT_INFINIBAND:
                if_initname(ifp, laggname, ifd->unit);
                ifp->if_transmit = lagg_transmit_infiniband;
                break;
        default:
                break;
        }
        ifp->if_softc = sc;
        ifp->if_qflush = lagg_qflush;
        ifp->if_init = lagg_init;
        ifp->if_ioctl = lagg_ioctl;
        ifp->if_get_counter = lagg_get_counter;
        ifp->if_flags = IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST;
#if defined(KERN_TLS) || defined(RATELIMIT)
        ifp->if_snd_tag_alloc = lagg_snd_tag_alloc;
        ifp->if_ratelimit_query = lagg_ratelimit_query;
#endif
        ifp->if_capenable = ifp->if_capabilities = IFCAP_HWSTATS;

        /*
         * Attach as an ordinary ethernet device, children will be attached
         * as special device IFT_IEEE8023ADLAG or IFT_INFINIBANDLAG.
         */
        switch (if_type) {
        case IFT_ETHER:
                ether_ifattach(ifp, eaddr);
                break;
        case IFT_INFINIBAND:
                infiniband_ifattach(ifp, eaddr, sc->sc_bcast_addr);
                break;
        default:
                break;
        }

        sc->vlan_attach = EVENTHANDLER_REGISTER(vlan_config,
                lagg_register_vlan, sc, EVENTHANDLER_PRI_FIRST);
        sc->vlan_detach = EVENTHANDLER_REGISTER(vlan_unconfig,
                lagg_unregister_vlan, sc, EVENTHANDLER_PRI_FIRST);

        /* Insert into the global list of laggs */
        LAGG_LIST_LOCK();
        SLIST_INSERT_HEAD(&V_lagg_list, sc, sc_entries);
        LAGG_LIST_UNLOCK();
        LAGG_XUNLOCK(sc);
        *ifpp = ifp;

        return (0);
}

static int
lagg_clone_destroy(struct if_clone *ifc, struct ifnet *ifp, uint32_t flags)
{
        struct lagg_softc *sc = (struct lagg_softc *)ifp->if_softc;
        struct lagg_port *lp;

        LAGG_XLOCK(sc);
        sc->sc_destroying = 1;
        lagg_stop(sc);
        ifp->if_flags &= ~IFF_UP;

        EVENTHANDLER_DEREGISTER(vlan_config, sc->vlan_attach);
        EVENTHANDLER_DEREGISTER(vlan_unconfig, sc->vlan_detach);

        /* Shutdown and remove lagg ports */
        while ((lp = CK_SLIST_FIRST(&sc->sc_ports)) != NULL)
                lagg_port_destroy(lp, 1);

        /* Unhook the aggregation protocol */
        lagg_proto_detach(sc);
        LAGG_XUNLOCK(sc);

        switch (ifp->if_type) {
        case IFT_ETHER:
                ether_ifdetach(ifp);
                ifmedia_removeall(&sc->sc_media);
                break;
        case IFT_INFINIBAND:
                infiniband_ifdetach(ifp);
                break;
        default:
                break;
        }
        if_free(ifp);

        LAGG_LIST_LOCK();
        SLIST_REMOVE(&V_lagg_list, sc, lagg_softc, sc_entries);
        LAGG_LIST_UNLOCK();

        mtx_destroy(&sc->sc_mtx);
        LAGG_SX_DESTROY(sc);
        free(sc, M_LAGG);

        return (0);
}

static void
lagg_capabilities(struct lagg_softc *sc)
{
        struct lagg_port *lp;
        int cap, cap2, ena, ena2, pena, pena2;
        uint64_t hwa;
        struct ifnet_hw_tsomax hw_tsomax;

        LAGG_XLOCK_ASSERT(sc);

        /* Get common enabled capabilities for the lagg ports */
        ena = ena2 = ~0;
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                ena &= lp->lp_ifp->if_capenable;
                ena2 &= lp->lp_ifp->if_capenable2;
        }
        if (CK_SLIST_FIRST(&sc->sc_ports) == NULL)
                ena = ena2 = 0;

        /*
         * Apply common enabled capabilities back to the lagg ports.
         * May require several iterations if they are dependent.
         */
        do {
                pena = ena;
                pena2 = ena2;
                CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                        lagg_setcaps(lp, ena, ena2);
                        ena &= lp->lp_ifp->if_capenable;
                        ena2 &= lp->lp_ifp->if_capenable2;
                }
        } while (pena != ena || pena2 != ena2);
        ena2 &= ~IFCAP2_BIT(IFCAP2_IPSEC_OFFLOAD);

        /* Get other capabilities from the lagg ports */
        cap = cap2 = ~0;
        hwa = ~(uint64_t)0;
        memset(&hw_tsomax, 0, sizeof(hw_tsomax));
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                cap &= lp->lp_ifp->if_capabilities;
                cap2 &= lp->lp_ifp->if_capabilities2;
                hwa &= lp->lp_ifp->if_hwassist;
                if_hw_tsomax_common(lp->lp_ifp, &hw_tsomax);
        }
        cap2 &= ~IFCAP2_BIT(IFCAP2_IPSEC_OFFLOAD);
        if (CK_SLIST_FIRST(&sc->sc_ports) == NULL)
                cap = cap2 = hwa = 0;

        if (sc->sc_ifp->if_capabilities != cap ||
            sc->sc_ifp->if_capenable != ena ||
            sc->sc_ifp->if_capenable2 != ena2 ||
            sc->sc_ifp->if_hwassist != hwa ||
            if_hw_tsomax_update(sc->sc_ifp, &hw_tsomax) != 0) {
                sc->sc_ifp->if_capabilities = cap;
                sc->sc_ifp->if_capabilities2 = cap2;
                sc->sc_ifp->if_capenable = ena;
                sc->sc_ifp->if_capenable2 = ena2;
                sc->sc_ifp->if_hwassist = hwa;
                (void)if_hw_tsomax_update(sc->sc_ifp, &hw_tsomax);
                getmicrotime(&sc->sc_ifp->if_lastchange);

                if (sc->sc_ifflags & IFF_DEBUG)
                        if_printf(sc->sc_ifp,
                            "capabilities 0x%08x enabled 0x%08x\n", cap, ena);
        }
}

static int
lagg_port_create(struct lagg_softc *sc, struct ifnet *ifp)
{
        struct lagg_softc *sc_ptr;
        struct lagg_port *lp, *tlp;
        struct ifreq ifr;
        int error, i, oldmtu;
        int if_type;
        uint64_t *pval;

        LAGG_XLOCK_ASSERT(sc);

        if (sc->sc_ifp == ifp) {
                if_printf(sc->sc_ifp,
                    "cannot add a lagg to itself as a port\n");
                return (EINVAL);
        }

        if (sc->sc_destroying == 1)
                return (ENXIO);

        /* Limit the maximal number of lagg ports */
        if (sc->sc_count >= LAGG_MAX_PORTS)
                return (ENOSPC);

        /* Check if port has already been associated to a lagg */
        if (ifp->if_lagg != NULL) {
                /* Port is already in the current lagg? */
                lp = (struct lagg_port *)ifp->if_lagg;
                if (lp->lp_softc == sc)
                        return (EEXIST);
                return (EBUSY);
        }

        switch (sc->sc_ifp->if_type) {
        case IFT_ETHER:
                /* XXX Disallow non-ethernet interfaces (this should be any of 802) */
                if (ifp->if_type != IFT_ETHER && ifp->if_type != IFT_L2VLAN)
                        return (EPROTONOSUPPORT);
                if_type = IFT_IEEE8023ADLAG;
                break;
        case IFT_INFINIBAND:
                /* XXX Disallow non-infiniband interfaces */
                if (ifp->if_type != IFT_INFINIBAND)
                        return (EPROTONOSUPPORT);
                if_type = IFT_INFINIBANDLAG;
                break;
        default:
                break;
        }

        /* Allow the first Ethernet member to define the MTU */
        oldmtu = -1;
        if (CK_SLIST_EMPTY(&sc->sc_ports)) {
                sc->sc_ifp->if_mtu = ifp->if_mtu;
        } else if (sc->sc_ifp->if_mtu != ifp->if_mtu) {
                if (ifp->if_ioctl == NULL) {
                        if_printf(sc->sc_ifp, "cannot change MTU for %s\n",
                            ifp->if_xname);
                        return (EINVAL);
                }
                oldmtu = ifp->if_mtu;
                strlcpy(ifr.ifr_name, ifp->if_xname, sizeof(ifr.ifr_name));
                ifr.ifr_mtu = sc->sc_ifp->if_mtu;
                error = (*ifp->if_ioctl)(ifp, SIOCSIFMTU, (caddr_t)&ifr);
                if (error != 0) {
                        if_printf(sc->sc_ifp, "invalid MTU for %s\n",
                            ifp->if_xname);
                        return (error);
                }
                ifr.ifr_mtu = oldmtu;
        }

        lp = malloc(sizeof(struct lagg_port), M_LAGG, M_WAITOK | M_ZERO);
        lp->lp_softc = sc;

        /* Check if port is a stacked lagg */
        LAGG_LIST_LOCK();
        SLIST_FOREACH(sc_ptr, &V_lagg_list, sc_entries) {
                if (ifp == sc_ptr->sc_ifp) {
                        LAGG_LIST_UNLOCK();
                        free(lp, M_LAGG);
                        if (oldmtu != -1)
                                (*ifp->if_ioctl)(ifp, SIOCSIFMTU,
                                    (caddr_t)&ifr);
                        return (EINVAL);
                        /* XXX disable stacking for the moment, its untested */
#ifdef LAGG_PORT_STACKING
                        lp->lp_flags |= LAGG_PORT_STACK;
                        if (lagg_port_checkstacking(sc_ptr) >=
                            LAGG_MAX_STACKING) {
                                LAGG_LIST_UNLOCK();
                                free(lp, M_LAGG);
                                if (oldmtu != -1)
                                        (*ifp->if_ioctl)(ifp, SIOCSIFMTU,
                                            (caddr_t)&ifr);
                                return (E2BIG);
                        }
#endif
                }
        }
        LAGG_LIST_UNLOCK();

        if_ref(ifp);
        lp->lp_ifp = ifp;

        bcopy(IF_LLADDR(ifp), lp->lp_lladdr, ifp->if_addrlen);
        lp->lp_ifcapenable = ifp->if_capenable;
        if (CK_SLIST_EMPTY(&sc->sc_ports)) {
                bcopy(IF_LLADDR(ifp), IF_LLADDR(sc->sc_ifp), ifp->if_addrlen);
                lagg_proto_lladdr(sc);
                EVENTHANDLER_INVOKE(iflladdr_event, sc->sc_ifp);
        } else {
                if_setlladdr(ifp, IF_LLADDR(sc->sc_ifp), ifp->if_addrlen);
        }
        lagg_setflags(lp, 1);

        if (CK_SLIST_EMPTY(&sc->sc_ports))
                sc->sc_primary = lp;

        /* Change the interface type */
        lp->lp_iftype = ifp->if_type;
        ifp->if_type = if_type;
        ifp->if_lagg = lp;
        lp->lp_ioctl = ifp->if_ioctl;
        ifp->if_ioctl = lagg_port_ioctl;
        lp->lp_output = ifp->if_output;
        ifp->if_output = lagg_port_output;

        /* Read port counters */
        pval = lp->port_counters.val;
        for (i = 0; i < IFCOUNTERS; i++, pval++)
                *pval = ifp->if_get_counter(ifp, i);

        /*
         * Insert into the list of ports.
         * Keep ports sorted by if_index. It is handy, when configuration
         * is predictable and `ifconfig laggN create ...` command
         * will lead to the same result each time.
         */
        CK_SLIST_FOREACH(tlp, &sc->sc_ports, lp_entries) {
                if (tlp->lp_ifp->if_index < ifp->if_index && (
                    CK_SLIST_NEXT(tlp, lp_entries) == NULL ||
                    ((struct lagg_port*)CK_SLIST_NEXT(tlp, lp_entries))->lp_ifp->if_index >
                    ifp->if_index))
                        break;
        }
        if (tlp != NULL)
                CK_SLIST_INSERT_AFTER(tlp, lp, lp_entries);
        else
                CK_SLIST_INSERT_HEAD(&sc->sc_ports, lp, lp_entries);
        sc->sc_count++;

        lagg_setmulti(lp);

        if ((error = lagg_proto_addport(sc, lp)) != 0) {
                /* Remove the port, without calling pr_delport. */
                lagg_port_destroy(lp, 0);
                if (oldmtu != -1)
                        (*ifp->if_ioctl)(ifp, SIOCSIFMTU, (caddr_t)&ifr);
                return (error);
        }

        /* Update lagg capabilities */
        lagg_capabilities(sc);
        lagg_linkstate(sc);

        return (0);
}

#ifdef LAGG_PORT_STACKING
static int
lagg_port_checkstacking(struct lagg_softc *sc)
{
        struct lagg_softc *sc_ptr;
        struct lagg_port *lp;
        int m = 0;

        LAGG_SXLOCK_ASSERT(sc);
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                if (lp->lp_flags & LAGG_PORT_STACK) {
                        sc_ptr = (struct lagg_softc *)lp->lp_ifp->if_softc;
                        m = MAX(m, lagg_port_checkstacking(sc_ptr));
                }
        }

        return (m + 1);
}
#endif

static void
lagg_port_destroy_cb(epoch_context_t ec)
{
        struct lagg_port *lp;
        struct ifnet *ifp;

        lp = __containerof(ec, struct lagg_port, lp_epoch_ctx);
        ifp = lp->lp_ifp;

        if_rele(ifp);
        free(lp, M_LAGG);
}

static int
lagg_port_destroy(struct lagg_port *lp, int rundelport)
{
        struct lagg_softc *sc = lp->lp_softc;
        struct lagg_port *lp_ptr, *lp0;
        struct ifnet *ifp = lp->lp_ifp;
        uint64_t *pval, vdiff;
        int i;

        LAGG_XLOCK_ASSERT(sc);

        if (rundelport)
                lagg_proto_delport(sc, lp);

        if (lp->lp_detaching == 0)
                lagg_clrmulti(lp);

        /* Restore interface */
        ifp->if_type = lp->lp_iftype;
        ifp->if_ioctl = lp->lp_ioctl;
        ifp->if_output = lp->lp_output;
        ifp->if_lagg = NULL;

        /* Update detached port counters */
        pval = lp->port_counters.val;
        for (i = 0; i < IFCOUNTERS; i++, pval++) {
                vdiff = ifp->if_get_counter(ifp, i) - *pval;
                sc->detached_counters.val[i] += vdiff;
        }

        /* Finally, remove the port from the lagg */
        CK_SLIST_REMOVE(&sc->sc_ports, lp, lagg_port, lp_entries);
        sc->sc_count--;

        /* Update the primary interface */
        if (lp == sc->sc_primary) {
                uint8_t lladdr[LAGG_ADDR_LEN];

                if ((lp0 = CK_SLIST_FIRST(&sc->sc_ports)) == NULL)
                        bzero(&lladdr, LAGG_ADDR_LEN);
                else
                        bcopy(lp0->lp_lladdr, lladdr, LAGG_ADDR_LEN);
                sc->sc_primary = lp0;
                if (sc->sc_destroying == 0) {
                        bcopy(lladdr, IF_LLADDR(sc->sc_ifp), sc->sc_ifp->if_addrlen);
                        lagg_proto_lladdr(sc);
                        EVENTHANDLER_INVOKE(iflladdr_event, sc->sc_ifp);

                        /*
                         * Update lladdr for each port (new primary needs update
                         * as well, to switch from old lladdr to its 'real' one).
                         * We can skip this if the lagg is being destroyed.
                         */
                        CK_SLIST_FOREACH(lp_ptr, &sc->sc_ports, lp_entries)
                                if_setlladdr(lp_ptr->lp_ifp, lladdr,
                                    lp_ptr->lp_ifp->if_addrlen);
                }
        }

        if (lp->lp_ifflags)
                if_printf(ifp, "%s: lp_ifflags unclean\n", __func__);

        if (lp->lp_detaching == 0) {
                lagg_setflags(lp, 0);
                lagg_setcaps(lp, lp->lp_ifcapenable, lp->lp_ifcapenable2);
                if_setlladdr(ifp, lp->lp_lladdr, ifp->if_addrlen);
        }

        /*
         * free port and release it's ifnet reference after a grace period has
         * elapsed.
         */
        NET_EPOCH_CALL(lagg_port_destroy_cb, &lp->lp_epoch_ctx);
        /* Update lagg capabilities */
        lagg_capabilities(sc);
        lagg_linkstate(sc);

        return (0);
}

static int
lagg_port_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
        struct lagg_reqport *rp = (struct lagg_reqport *)data;
        struct lagg_softc *sc;
        struct lagg_port *lp = NULL;
        int error = 0;

        /* Should be checked by the caller */
        switch (ifp->if_type) {
        case IFT_IEEE8023ADLAG:
        case IFT_INFINIBANDLAG:
                if ((lp = ifp->if_lagg) == NULL || (sc = lp->lp_softc) == NULL)
                        goto fallback;
                break;
        default:
                goto fallback;
        }

        switch (cmd) {
        case SIOCGLAGGPORT:
                if (rp->rp_portname[0] == '\0' ||
                    ifunit(rp->rp_portname) != ifp) {
                        error = EINVAL;
                        break;
                }

                LAGG_SLOCK(sc);
                if (__predict_true((lp = ifp->if_lagg) != NULL &&
                    lp->lp_softc == sc))
                        lagg_port2req(lp, rp);
                else
                        error = ENOENT; /* XXXGL: can happen? */
                LAGG_SUNLOCK(sc);
                break;

        case SIOCSIFCAP:
        case SIOCSIFCAPNV:
                if (lp->lp_ioctl == NULL) {
                        error = EINVAL;
                        break;
                }
                error = (*lp->lp_ioctl)(ifp, cmd, data);
                if (error)
                        break;

                /* Update lagg interface capabilities */
                LAGG_XLOCK(sc);
                lagg_capabilities(sc);
                LAGG_XUNLOCK(sc);
                VLAN_CAPABILITIES(sc->sc_ifp);
                break;

        case SIOCSIFMTU:
                /* Do not allow the MTU to be changed once joined */
                error = EINVAL;
                break;

        default:
                goto fallback;
        }

        return (error);

fallback:
        if (lp != NULL && lp->lp_ioctl != NULL)
                return ((*lp->lp_ioctl)(ifp, cmd, data));

        return (EINVAL);
}

/*
 * Requests counter @cnt data.
 *
 * Counter value is calculated the following way:
 * 1) for each port, sum difference between current and "initial" measurements.
 * 2) add lagg logical interface counters.
 * 3) add data from detached_counters array.
 *
 * We also do the following things on ports attach/detach:
 * 1) On port attach we store all counters it has into port_counter array.
 * 2) On port detach we add the different between "initial" and
 *   current counters data to detached_counters array.
 */
static uint64_t
lagg_get_counter(struct ifnet *ifp, ift_counter cnt)
{
        struct epoch_tracker et;
        struct lagg_softc *sc;
        struct lagg_port *lp;
        struct ifnet *lpifp;
        uint64_t newval, oldval, vsum;

        /* Revise this when we've got non-generic counters. */
        KASSERT(cnt < IFCOUNTERS, ("%s: invalid cnt %d", __func__, cnt));

        sc = (struct lagg_softc *)ifp->if_softc;

        vsum = 0;
        NET_EPOCH_ENTER(et);
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                /* Saved attached value */
                oldval = lp->port_counters.val[cnt];
                /* current value */
                lpifp = lp->lp_ifp;
                newval = lpifp->if_get_counter(lpifp, cnt);
                /* Calculate diff and save new */
                vsum += newval - oldval;
        }
        NET_EPOCH_EXIT(et);

        /*
         * Add counter data which might be added by upper
         * layer protocols operating on logical interface.
         */
        vsum += if_get_counter_default(ifp, cnt);

        /*
         * Add counter data from detached ports counters
         */
        vsum += sc->detached_counters.val[cnt];

        return (vsum);
}

/*
 * For direct output to child ports.
 */
static int
lagg_port_output(struct ifnet *ifp, struct mbuf *m,
        const struct sockaddr *dst, struct route *ro)
{
        struct lagg_port *lp = ifp->if_lagg;

        switch (dst->sa_family) {
                case pseudo_AF_HDRCMPLT:
                case AF_UNSPEC:
                        if (lp != NULL)
                                return ((*lp->lp_output)(ifp, m, dst, ro));
        }

        /* drop any other frames */
        m_freem(m);
        return (ENETDOWN);
}

static void
lagg_port_ifdetach(void *arg __unused, struct ifnet *ifp)
{
        struct lagg_port *lp;
        struct lagg_softc *sc;

        if ((lp = ifp->if_lagg) == NULL)
                return;

        sc = lp->lp_softc;

        LAGG_XLOCK(sc);
        lp->lp_detaching = 1;
        lagg_port_destroy(lp, 1);
        LAGG_XUNLOCK(sc);
        VLAN_CAPABILITIES(sc->sc_ifp);
}

static void
lagg_port2req(struct lagg_port *lp, struct lagg_reqport *rp)
{
        struct lagg_softc *sc = lp->lp_softc;

        strlcpy(rp->rp_ifname, sc->sc_ifname, sizeof(rp->rp_ifname));
        strlcpy(rp->rp_portname, lp->lp_ifp->if_xname, sizeof(rp->rp_portname));
        rp->rp_prio = lp->lp_prio;
        rp->rp_flags = lp->lp_flags;
        lagg_proto_portreq(sc, lp, &rp->rp_psc);

        /* Add protocol specific flags */
        switch (sc->sc_proto) {
                case LAGG_PROTO_FAILOVER:
                        if (lp == sc->sc_primary)
                                rp->rp_flags |= LAGG_PORT_MASTER;
                        if (lp == lagg_link_active(sc, sc->sc_primary))
                                rp->rp_flags |= LAGG_PORT_ACTIVE;
                        break;

                case LAGG_PROTO_ROUNDROBIN:
                case LAGG_PROTO_LOADBALANCE:
                case LAGG_PROTO_BROADCAST:
                        if (LAGG_PORTACTIVE(lp))
                                rp->rp_flags |= LAGG_PORT_ACTIVE;
                        break;

                case LAGG_PROTO_LACP:
                        /* LACP has a different definition of active */
                        if (lacp_isactive(lp))
                                rp->rp_flags |= LAGG_PORT_ACTIVE;
                        if (lacp_iscollecting(lp))
                                rp->rp_flags |= LAGG_PORT_COLLECTING;
                        if (lacp_isdistributing(lp))
                                rp->rp_flags |= LAGG_PORT_DISTRIBUTING;
                        break;
        }

}

static void
lagg_watchdog_infiniband(void *arg)
{
        struct epoch_tracker et;
        struct lagg_softc *sc;
        struct lagg_port *lp;
        struct ifnet *ifp;
        struct ifnet *lp_ifp;

        sc = arg;

        /*
         * Because infiniband nodes have a fixed MAC address, which is
         * generated by the so-called GID, we need to regularly update
         * the link level address of the parent lagg<N> device when
         * the active port changes. Possibly we could piggy-back on
         * link up/down events aswell, but using a timer also provides
         * a guarantee against too frequent events. This operation
         * does not have to be atomic.
         */
        NET_EPOCH_ENTER(et);
        lp = lagg_link_active(sc, sc->sc_primary);
        if (lp != NULL) {
                ifp = sc->sc_ifp;
                lp_ifp = lp->lp_ifp;

                if (ifp != NULL && lp_ifp != NULL &&
                    (memcmp(IF_LLADDR(ifp), IF_LLADDR(lp_ifp), ifp->if_addrlen) != 0 ||
                     memcmp(sc->sc_bcast_addr, lp_ifp->if_broadcastaddr, ifp->if_addrlen) != 0)) {
                        memcpy(IF_LLADDR(ifp), IF_LLADDR(lp_ifp), ifp->if_addrlen);
                        memcpy(sc->sc_bcast_addr, lp_ifp->if_broadcastaddr, ifp->if_addrlen);

                        CURVNET_SET(ifp->if_vnet);
                        EVENTHANDLER_INVOKE(iflladdr_event, ifp);
                        CURVNET_RESTORE();
                }
        }
        NET_EPOCH_EXIT(et);

        callout_reset(&sc->sc_watchdog, hz, &lagg_watchdog_infiniband, arg);
}

static void
lagg_if_updown(struct lagg_softc *sc, bool up)
{
        struct ifreq ifr = {};
        struct lagg_port *lp;

        LAGG_XLOCK_ASSERT(sc);

        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                if (up)
                        if_up(lp->lp_ifp);
                else
                        if_down(lp->lp_ifp);

                if (lp->lp_ioctl != NULL)
                        lp->lp_ioctl(lp->lp_ifp, SIOCSIFFLAGS, (caddr_t)&ifr);
        }
}

static void
lagg_init(void *xsc)
{
        struct lagg_softc *sc = (struct lagg_softc *)xsc;

        LAGG_XLOCK(sc);
        lagg_init_locked(sc);
        LAGG_XUNLOCK(sc);
}

static void
lagg_init_locked(struct lagg_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct lagg_port *lp;

        LAGG_XLOCK_ASSERT(sc);
        if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
                return;

        /*
         * Update the port lladdrs if needed.
         * This might be if_setlladdr() notification
         * that lladdr has been changed.
         */
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                if (memcmp(IF_LLADDR(ifp), IF_LLADDR(lp->lp_ifp),
                    ifp->if_addrlen) != 0)
                        if_setlladdr(lp->lp_ifp, IF_LLADDR(ifp), ifp->if_addrlen);
        }

        lagg_if_updown(sc, true);

        lagg_proto_init(sc);

        if (ifp->if_type == IFT_INFINIBAND) {
                mtx_lock(&sc->sc_mtx);
                lagg_watchdog_infiniband(sc);
                mtx_unlock(&sc->sc_mtx);
        }
        ifp->if_drv_flags |= IFF_DRV_RUNNING;
}

static void
lagg_stop(struct lagg_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;

        LAGG_XLOCK_ASSERT(sc);

        if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
                return;

        ifp->if_drv_flags &= ~IFF_DRV_RUNNING;

        lagg_proto_stop(sc);

        mtx_lock(&sc->sc_mtx);
        callout_stop(&sc->sc_watchdog);
        mtx_unlock(&sc->sc_mtx);

        lagg_if_updown(sc, false);

        callout_drain(&sc->sc_watchdog);
}

static int
lagg_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
        struct lagg_softc *sc = (struct lagg_softc *)ifp->if_softc;
        struct lagg_reqall *ra = (struct lagg_reqall *)data;
        struct lagg_reqopts *ro = (struct lagg_reqopts *)data;
        struct lagg_reqport *rp = (struct lagg_reqport *)data, rpbuf;
        struct lagg_reqflags *rf = (struct lagg_reqflags *)data;
        struct ifreq *ifr = (struct ifreq *)data;
        struct lagg_port *lp;
        struct ifnet *tpif;
        struct thread *td = curthread;
        char *buf, *outbuf;
        int count, buflen, len, error = 0, oldmtu;

        bzero(&rpbuf, sizeof(rpbuf));

        /* XXX: This can race with lagg_clone_destroy. */

        switch (cmd) {
        case SIOCGLAGG:
                LAGG_XLOCK(sc);
                buflen = sc->sc_count * sizeof(struct lagg_reqport);
                outbuf = malloc(buflen, M_TEMP, M_WAITOK | M_ZERO);
                ra->ra_proto = sc->sc_proto;
                lagg_proto_request(sc, &ra->ra_psc);
                count = 0;
                buf = outbuf;
                len = min(ra->ra_size, buflen);
                CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                        if (len < sizeof(rpbuf))
                                break;

                        lagg_port2req(lp, &rpbuf);
                        memcpy(buf, &rpbuf, sizeof(rpbuf));
                        count++;
                        buf += sizeof(rpbuf);
                        len -= sizeof(rpbuf);
                }
                LAGG_XUNLOCK(sc);
                ra->ra_ports = count;
                ra->ra_size = count * sizeof(rpbuf);
                error = copyout(outbuf, ra->ra_port, ra->ra_size);
                free(outbuf, M_TEMP);
                break;
        case SIOCSLAGG:
                error = priv_check(td, PRIV_NET_LAGG);
                if (error)
                        break;
                if (ra->ra_proto >= LAGG_PROTO_MAX) {
                        error = EPROTONOSUPPORT;
                        break;
                }
                /* Infiniband only supports the failover protocol. */
                if (ra->ra_proto != LAGG_PROTO_FAILOVER &&
                    ifp->if_type == IFT_INFINIBAND) {
                        error = EPROTONOSUPPORT;
                        break;
                }
                LAGG_XLOCK(sc);
                lagg_proto_detach(sc);
                lagg_proto_attach(sc, ra->ra_proto);
                LAGG_XUNLOCK(sc);
                break;
        case SIOCGLAGGOPTS:
                LAGG_XLOCK(sc);
                ro->ro_opts = sc->sc_opts;
                if (sc->sc_proto == LAGG_PROTO_LACP) {
                        struct lacp_softc *lsc;

                        lsc = (struct lacp_softc *)sc->sc_psc;
                        if (lsc->lsc_debug.lsc_tx_test != 0)
                                ro->ro_opts |= LAGG_OPT_LACP_TXTEST;
                        if (lsc->lsc_debug.lsc_rx_test != 0)
                                ro->ro_opts |= LAGG_OPT_LACP_RXTEST;
                        if (lsc->lsc_strict_mode != 0)
                                ro->ro_opts |= LAGG_OPT_LACP_STRICT;
                        if (lsc->lsc_fast_timeout != 0)
                                ro->ro_opts |= LAGG_OPT_LACP_FAST_TIMO;

                        ro->ro_active = sc->sc_active;
                } else {
                        ro->ro_active = 0;
                        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries)
                                ro->ro_active += LAGG_PORTACTIVE(lp);
                }
                ro->ro_bkt = sc->sc_stride;
                ro->ro_flapping = sc->sc_flapping;
                ro->ro_flowid_shift = sc->flowid_shift;
                LAGG_XUNLOCK(sc);
                break;
        case SIOCSLAGGOPTS:
                error = priv_check(td, PRIV_NET_LAGG);
                if (error)
                        break;

                /*
                 * The stride option was added without defining a corresponding
                 * LAGG_OPT flag, so handle a non-zero value before checking
                 * anything else to preserve compatibility.
                 */
                LAGG_XLOCK(sc);
                if (ro->ro_opts == 0 && ro->ro_bkt != 0) {
                        if (sc->sc_proto != LAGG_PROTO_ROUNDROBIN) {
                                LAGG_XUNLOCK(sc);
                                error = EINVAL;
                                break;
                        }
                        sc->sc_stride = ro->ro_bkt;
                }
                if (ro->ro_opts == 0) {
                        LAGG_XUNLOCK(sc);
                        break;
                }

                /*
                 * Set options.  LACP options are stored in sc->sc_psc,
                 * not in sc_opts.
                 */
                int valid, lacp;

                switch (ro->ro_opts) {
                case LAGG_OPT_USE_FLOWID:
                case -LAGG_OPT_USE_FLOWID:
                case LAGG_OPT_USE_NUMA:
                case -LAGG_OPT_USE_NUMA:
                case LAGG_OPT_FLOWIDSHIFT:
                case LAGG_OPT_RR_LIMIT:
                        valid = 1;
                        lacp = 0;
                        break;
                case LAGG_OPT_LACP_TXTEST:
                case -LAGG_OPT_LACP_TXTEST:
                case LAGG_OPT_LACP_RXTEST:
                case -LAGG_OPT_LACP_RXTEST:
                case LAGG_OPT_LACP_STRICT:
                case -LAGG_OPT_LACP_STRICT:
                case LAGG_OPT_LACP_FAST_TIMO:
                case -LAGG_OPT_LACP_FAST_TIMO:
                        valid = lacp = 1;
                        break;
                default:
                        valid = lacp = 0;
                        break;
                }

                if (valid == 0 ||
                    (lacp == 1 && sc->sc_proto != LAGG_PROTO_LACP)) {
                        /* Invalid combination of options specified. */
                        error = EINVAL;
                        LAGG_XUNLOCK(sc);
                        break;  /* Return from SIOCSLAGGOPTS. */
                }

                /*
                 * Store new options into sc->sc_opts except for
                 * FLOWIDSHIFT, RR and LACP options.
                 */
                if (lacp == 0) {
                        if (ro->ro_opts == LAGG_OPT_FLOWIDSHIFT)
                                sc->flowid_shift = ro->ro_flowid_shift;
                        else if (ro->ro_opts == LAGG_OPT_RR_LIMIT) {
                                if (sc->sc_proto != LAGG_PROTO_ROUNDROBIN ||
                                    ro->ro_bkt == 0) {
                                        error = EINVAL;
                                        LAGG_XUNLOCK(sc);
                                        break;
                                }
                                sc->sc_stride = ro->ro_bkt;
                        } else if (ro->ro_opts > 0)
                                sc->sc_opts |= ro->ro_opts;
                        else
                                sc->sc_opts &= ~ro->ro_opts;
                } else {
                        struct lacp_softc *lsc;
                        struct lacp_port *lp;

                        lsc = (struct lacp_softc *)sc->sc_psc;

                        switch (ro->ro_opts) {
                        case LAGG_OPT_LACP_TXTEST:
                                lsc->lsc_debug.lsc_tx_test = 1;
                                break;
                        case -LAGG_OPT_LACP_TXTEST:
                                lsc->lsc_debug.lsc_tx_test = 0;
                                break;
                        case LAGG_OPT_LACP_RXTEST:
                                lsc->lsc_debug.lsc_rx_test = 1;
                                break;
                        case -LAGG_OPT_LACP_RXTEST:
                                lsc->lsc_debug.lsc_rx_test = 0;
                                break;
                        case LAGG_OPT_LACP_STRICT:
                                lsc->lsc_strict_mode = 1;
                                break;
                        case -LAGG_OPT_LACP_STRICT:
                                lsc->lsc_strict_mode = 0;
                                break;
                        case LAGG_OPT_LACP_FAST_TIMO:
                                LACP_LOCK(lsc);
                                LIST_FOREACH(lp, &lsc->lsc_ports, lp_next)
                                        lp->lp_state |= LACP_STATE_TIMEOUT;
                                LACP_UNLOCK(lsc);
                                lsc->lsc_fast_timeout = 1;
                                break;
                        case -LAGG_OPT_LACP_FAST_TIMO:
                                LACP_LOCK(lsc);
                                LIST_FOREACH(lp, &lsc->lsc_ports, lp_next)
                                        lp->lp_state &= ~LACP_STATE_TIMEOUT;
                                LACP_UNLOCK(lsc);
                                lsc->lsc_fast_timeout = 0;
                                break;
                        }
                }
                LAGG_XUNLOCK(sc);
                break;
        case SIOCGLAGGFLAGS:
                rf->rf_flags = 0;
                LAGG_XLOCK(sc);
                if (sc->sc_flags & MBUF_HASHFLAG_L2)
                        rf->rf_flags |= LAGG_F_HASHL2;
                if (sc->sc_flags & MBUF_HASHFLAG_L3)
                        rf->rf_flags |= LAGG_F_HASHL3;
                if (sc->sc_flags & MBUF_HASHFLAG_L4)
                        rf->rf_flags |= LAGG_F_HASHL4;
                LAGG_XUNLOCK(sc);
                break;
        case SIOCSLAGGHASH:
                error = priv_check(td, PRIV_NET_LAGG);
                if (error)
                        break;
                if ((rf->rf_flags & LAGG_F_HASHMASK) == 0) {
                        error = EINVAL;
                        break;
                }
                LAGG_XLOCK(sc);
                sc->sc_flags = 0;
                if (rf->rf_flags & LAGG_F_HASHL2)
                        sc->sc_flags |= MBUF_HASHFLAG_L2;
                if (rf->rf_flags & LAGG_F_HASHL3)
                        sc->sc_flags |= MBUF_HASHFLAG_L3;
                if (rf->rf_flags & LAGG_F_HASHL4)
                        sc->sc_flags |= MBUF_HASHFLAG_L4;
                LAGG_XUNLOCK(sc);
                break;
        case SIOCGLAGGPORT:
                if (rp->rp_portname[0] == '\0' ||
                    (tpif = ifunit_ref(rp->rp_portname)) == NULL) {
                        error = EINVAL;
                        break;
                }

                LAGG_SLOCK(sc);
                if (__predict_true((lp = tpif->if_lagg) != NULL &&
                    lp->lp_softc == sc))
                        lagg_port2req(lp, rp);
                else
                        error = ENOENT; /* XXXGL: can happen? */
                LAGG_SUNLOCK(sc);
                if_rele(tpif);
                break;

        case SIOCSLAGGPORT:
                error = priv_check(td, PRIV_NET_LAGG);
                if (error)
                        break;
                if (rp->rp_portname[0] == '\0' ||
                    (tpif = ifunit_ref(rp->rp_portname)) == NULL) {
                        error = EINVAL;
                        break;
                }
#ifdef INET6
                /*
                 * A laggport interface should not have inet6 address
                 * because two interfaces with a valid link-local
                 * scope zone must not be merged in any form.  This
                 * restriction is needed to prevent violation of
                 * link-local scope zone.  Attempts to add a laggport
                 * interface which has inet6 addresses triggers
                 * removal of all inet6 addresses on the member
                 * interface.
                 */
                if (in6ifa_llaonifp(tpif)) {
                        in6_ifdetach(tpif);
                                if_printf(sc->sc_ifp,
                                    "IPv6 addresses on %s have been removed "
                                    "before adding it as a member to prevent "
                                    "IPv6 address scope violation.\n",
                                    tpif->if_xname);
                }
#endif
                oldmtu = ifp->if_mtu;
                LAGG_XLOCK(sc);
                error = lagg_port_create(sc, tpif);
                LAGG_XUNLOCK(sc);
                if_rele(tpif);

                /*
                 * LAGG MTU may change during addition of the first port.
                 * If it did, do network layer specific procedure.
                 */
                if (ifp->if_mtu != oldmtu)
                        if_notifymtu(ifp);

                VLAN_CAPABILITIES(ifp);
                break;
        case SIOCSLAGGDELPORT:
                error = priv_check(td, PRIV_NET_LAGG);
                if (error)
                        break;
                if (rp->rp_portname[0] == '\0' ||
                    (tpif = ifunit_ref(rp->rp_portname)) == NULL) {
                        error = EINVAL;
                        break;
                }

                LAGG_XLOCK(sc);
                if ((lp = (struct lagg_port *)tpif->if_lagg) == NULL ||
                    lp->lp_softc != sc) {
                        error = ENOENT;
                        LAGG_XUNLOCK(sc);
                        if_rele(tpif);
                        break;
                }

                error = lagg_port_destroy(lp, 1);
                LAGG_XUNLOCK(sc);
                if_rele(tpif);
                VLAN_CAPABILITIES(ifp);
                break;
        case SIOCSIFFLAGS:
                /* Set flags on ports too */
                LAGG_XLOCK(sc);
                CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                        lagg_setflags(lp, 1);
                }

                if ((ifp->if_flags & IFF_UP) == 0 &&
                    (ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
                        /*
                         * If interface is marked down and it is running,
                         * then stop and disable it.
                         */
                        lagg_stop(sc);
                else if ((ifp->if_flags & IFF_UP) != 0 &&
                    (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
                        /*
                         * If interface is marked up and it is stopped, then
                         * start it.
                         */
                        lagg_init_locked(sc);
                LAGG_XUNLOCK(sc);
                break;
        case SIOCADDMULTI:
        case SIOCDELMULTI:
                LAGG_XLOCK(sc);
                CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                        lagg_clrmulti(lp);
                        lagg_setmulti(lp);
                }
                LAGG_XUNLOCK(sc);
                error = 0;
                break;
        case SIOCSIFMEDIA:
        case SIOCGIFMEDIA:
                if (ifp->if_type == IFT_INFINIBAND)
                        error = EINVAL;
                else
                        error = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd);
                break;

        case SIOCSIFCAP:
        case SIOCSIFCAPNV:
                LAGG_XLOCK(sc);
                CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                        if (lp->lp_ioctl != NULL)
                                (*lp->lp_ioctl)(lp->lp_ifp, cmd, data);
                }
                lagg_capabilities(sc);
                LAGG_XUNLOCK(sc);
                VLAN_CAPABILITIES(ifp);
                error = 0;
                break;

        case SIOCGIFCAPNV:
                error = 0;
                break;

        case SIOCSIFMTU:
                LAGG_XLOCK(sc);
                CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                        if (lp->lp_ioctl != NULL)
                                error = (*lp->lp_ioctl)(lp->lp_ifp, cmd, data);
                        else
                                error = EINVAL;
                        if (error != 0) {
                                if_printf(ifp,
                                    "failed to change MTU to %d on port %s, "
                                    "reverting all ports to original MTU (%d)\n",
                                    ifr->ifr_mtu, lp->lp_ifp->if_xname, ifp->if_mtu);
                                break;
                        }
                }
                if (error == 0) {
                        ifp->if_mtu = ifr->ifr_mtu;
                } else {
                        /* set every port back to the original MTU */
                        ifr->ifr_mtu = ifp->if_mtu;
                        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                                if (lp->lp_ioctl != NULL)
                                        (*lp->lp_ioctl)(lp->lp_ifp, cmd, data);
                        }
                }
                lagg_capabilities(sc);
                LAGG_XUNLOCK(sc);
                VLAN_CAPABILITIES(ifp);
                break;

        default:
                error = ether_ioctl(ifp, cmd, data);
                break;
        }
        return (error);
}

#if defined(KERN_TLS) || defined(RATELIMIT)
#ifdef RATELIMIT
static const struct if_snd_tag_sw lagg_snd_tag_ul_sw = {
        .snd_tag_modify = lagg_snd_tag_modify,
        .snd_tag_query = lagg_snd_tag_query,
        .snd_tag_free = lagg_snd_tag_free,
        .next_snd_tag = lagg_next_snd_tag,
        .type = IF_SND_TAG_TYPE_UNLIMITED
};

static const struct if_snd_tag_sw lagg_snd_tag_rl_sw = {
        .snd_tag_modify = lagg_snd_tag_modify,
        .snd_tag_query = lagg_snd_tag_query,
        .snd_tag_free = lagg_snd_tag_free,
        .next_snd_tag = lagg_next_snd_tag,
        .type = IF_SND_TAG_TYPE_RATE_LIMIT
};
#endif

#ifdef KERN_TLS
static const struct if_snd_tag_sw lagg_snd_tag_tls_sw = {
        .snd_tag_modify = lagg_snd_tag_modify,
        .snd_tag_query = lagg_snd_tag_query,
        .snd_tag_free = lagg_snd_tag_free,
        .next_snd_tag = lagg_next_snd_tag,
        .type = IF_SND_TAG_TYPE_TLS
};

#ifdef RATELIMIT
static const struct if_snd_tag_sw lagg_snd_tag_tls_rl_sw = {
        .snd_tag_modify = lagg_snd_tag_modify,
        .snd_tag_query = lagg_snd_tag_query,
        .snd_tag_free = lagg_snd_tag_free,
        .next_snd_tag = lagg_next_snd_tag,
        .type = IF_SND_TAG_TYPE_TLS_RATE_LIMIT
};
#endif
#endif

static inline struct lagg_snd_tag *
mst_to_lst(struct m_snd_tag *mst)
{

        return (__containerof(mst, struct lagg_snd_tag, com));
}

/*
 * Look up the port used by a specific flow.  This only works for lagg
 * protocols with deterministic port mappings (e.g. not roundrobin).
 * In addition protocols which use a hash to map flows to ports must
 * be configured to use the mbuf flowid rather than hashing packet
 * contents.
 */
static struct lagg_port *
lookup_snd_tag_port(struct ifnet *ifp, uint32_t flowid, uint32_t flowtype,
    uint8_t numa_domain)
{
        struct lagg_softc *sc;
        struct lagg_port *lp;
        struct lagg_lb *lb;
        uint32_t hash, p;
        int err;

        sc = ifp->if_softc;

        switch (sc->sc_proto) {
        case LAGG_PROTO_FAILOVER:
                return (lagg_link_active(sc, sc->sc_primary));
        case LAGG_PROTO_LOADBALANCE:
                if ((sc->sc_opts & LAGG_OPT_USE_FLOWID) == 0 ||
                    flowtype == M_HASHTYPE_NONE)
                        return (NULL);
                p = flowid >> sc->flowid_shift;
                p %= sc->sc_count;
                lb = (struct lagg_lb *)sc->sc_psc;
                lp = lb->lb_ports[p];
                return (lagg_link_active(sc, lp));
        case LAGG_PROTO_LACP:
                if ((sc->sc_opts & LAGG_OPT_USE_FLOWID) == 0 ||
                    flowtype == M_HASHTYPE_NONE)
                        return (NULL);
                hash = flowid >> sc->flowid_shift;
                return (lacp_select_tx_port_by_hash(sc, hash, numa_domain, &err));
        default:
                return (NULL);
        }
}

static int
lagg_snd_tag_alloc(struct ifnet *ifp,
    union if_snd_tag_alloc_params *params,
    struct m_snd_tag **ppmt)
{
        struct epoch_tracker et;
        const struct if_snd_tag_sw *sw;
        struct lagg_snd_tag *lst;
        struct lagg_port *lp;
        struct ifnet *lp_ifp;
        struct m_snd_tag *mst;
        int error;

        switch (params->hdr.type) {
#ifdef RATELIMIT
        case IF_SND_TAG_TYPE_UNLIMITED:
                sw = &lagg_snd_tag_ul_sw;
                break;
        case IF_SND_TAG_TYPE_RATE_LIMIT:
                sw = &lagg_snd_tag_rl_sw;
                break;
#endif
#ifdef KERN_TLS
        case IF_SND_TAG_TYPE_TLS:
                sw = &lagg_snd_tag_tls_sw;
                break;
        case IF_SND_TAG_TYPE_TLS_RX:
                /* Return tag from port interface directly. */
                sw = NULL;
                break;
#ifdef RATELIMIT
        case IF_SND_TAG_TYPE_TLS_RATE_LIMIT:
                sw = &lagg_snd_tag_tls_rl_sw;
                break;
#endif
#endif
        default:
                return (EOPNOTSUPP);
        }

        NET_EPOCH_ENTER(et);
        lp = lookup_snd_tag_port(ifp, params->hdr.flowid,
            params->hdr.flowtype, params->hdr.numa_domain);
        if (lp == NULL) {
                NET_EPOCH_EXIT(et);
                return (EOPNOTSUPP);
        }
        if (lp->lp_ifp == NULL) {
                NET_EPOCH_EXIT(et);
                return (EOPNOTSUPP);
        }
        lp_ifp = lp->lp_ifp;
        if_ref(lp_ifp);
        NET_EPOCH_EXIT(et);

        if (sw != NULL) {
                lst = malloc(sizeof(*lst), M_LAGG, M_NOWAIT);
                if (lst == NULL) {
                        if_rele(lp_ifp);
                        return (ENOMEM);
                }
        } else
                lst = NULL;

        error = m_snd_tag_alloc(lp_ifp, params, &mst);
        if_rele(lp_ifp);
        if (error) {
                free(lst, M_LAGG);
                return (error);
        }

        if (sw != NULL) {
                m_snd_tag_init(&lst->com, ifp, sw);
                lst->tag = mst;

                *ppmt = &lst->com;
        } else
                *ppmt = mst;

        return (0);
}

static struct m_snd_tag *
lagg_next_snd_tag(struct m_snd_tag *mst)
{
        struct lagg_snd_tag *lst;

        lst = mst_to_lst(mst);
        return (lst->tag);
}

static int
lagg_snd_tag_modify(struct m_snd_tag *mst,
    union if_snd_tag_modify_params *params)
{
        struct lagg_snd_tag *lst;

        lst = mst_to_lst(mst);
        return (lst->tag->sw->snd_tag_modify(lst->tag, params));
}

static int
lagg_snd_tag_query(struct m_snd_tag *mst,
    union if_snd_tag_query_params *params)
{
        struct lagg_snd_tag *lst;

        lst = mst_to_lst(mst);
        return (lst->tag->sw->snd_tag_query(lst->tag, params));
}

static void
lagg_snd_tag_free(struct m_snd_tag *mst)
{
        struct lagg_snd_tag *lst;

        lst = mst_to_lst(mst);
        m_snd_tag_rele(lst->tag);
        free(lst, M_LAGG);
}

static void
lagg_ratelimit_query(struct ifnet *ifp __unused, struct if_ratelimit_query_results *q)
{
        /*
         * For lagg, we have an indirect
         * interface. The caller needs to
         * get a ratelimit tag on the actual
         * interface the flow will go on.
         */
        q->rate_table = NULL;
        q->flags = RT_IS_INDIRECT;
        q->max_flows = 0;
        q->number_of_rates = 0;
}
#endif

static int
lagg_setmulti(struct lagg_port *lp)
{
        struct lagg_softc *sc = lp->lp_softc;
        struct ifnet *ifp = lp->lp_ifp;
        struct ifnet *scifp = sc->sc_ifp;
        struct lagg_mc *mc;
        struct ifmultiaddr *ifma;
        int error;

        IF_ADDR_WLOCK(scifp);
        CK_STAILQ_FOREACH(ifma, &scifp->if_multiaddrs, ifma_link) {
                if (ifma->ifma_addr->sa_family != AF_LINK)
                        continue;
                mc = malloc(sizeof(struct lagg_mc), M_LAGG, M_NOWAIT);
                if (mc == NULL) {
                        IF_ADDR_WUNLOCK(scifp);
                        return (ENOMEM);
                }
                bcopy(ifma->ifma_addr, &mc->mc_addr, ifma->ifma_addr->sa_len);
                mc->mc_addr.sdl_index = ifp->if_index;
                mc->mc_ifma = NULL;
                SLIST_INSERT_HEAD(&lp->lp_mc_head, mc, mc_entries);
        }
        IF_ADDR_WUNLOCK(scifp);
        SLIST_FOREACH (mc, &lp->lp_mc_head, mc_entries) {
                error = if_addmulti(ifp,
                    (struct sockaddr *)&mc->mc_addr, &mc->mc_ifma);
                if (error)
                        return (error);
        }
        return (0);
}

static int
lagg_clrmulti(struct lagg_port *lp)
{
        struct lagg_mc *mc;

        LAGG_XLOCK_ASSERT(lp->lp_softc);
        while ((mc = SLIST_FIRST(&lp->lp_mc_head)) != NULL) {
                SLIST_REMOVE(&lp->lp_mc_head, mc, lagg_mc, mc_entries);
                if (mc->mc_ifma && lp->lp_detaching == 0)
                        if_delmulti_ifma(mc->mc_ifma);
                free(mc, M_LAGG);
        }
        return (0);
}

static void
lagg_setcaps(struct lagg_port *lp, int cap, int cap2)
{
        struct ifreq ifr;
        struct siocsifcapnv_driver_data drv_ioctl_data;

        if (lp->lp_ifp->if_capenable == cap &&
            lp->lp_ifp->if_capenable2 == cap2)
                return;
        if (lp->lp_ioctl == NULL)
                return;
        /* XXX */
        if ((lp->lp_ifp->if_capabilities & IFCAP_NV) != 0) {
                drv_ioctl_data.reqcap = cap;
                drv_ioctl_data.reqcap2 = cap2;
                drv_ioctl_data.nvcap = NULL;
                (*lp->lp_ioctl)(lp->lp_ifp, SIOCSIFCAPNV,
                    (caddr_t)&drv_ioctl_data);
        } else {
                ifr.ifr_reqcap = cap;
                (*lp->lp_ioctl)(lp->lp_ifp, SIOCSIFCAP, (caddr_t)&ifr);
        }
}

/* Handle a ref counted flag that should be set on the lagg port as well */
static int
lagg_setflag(struct lagg_port *lp, int flag, int status,
    int (*func)(struct ifnet *, int))
{
        struct lagg_softc *sc = lp->lp_softc;
        struct ifnet *scifp = sc->sc_ifp;
        struct ifnet *ifp = lp->lp_ifp;
        int error;

        LAGG_XLOCK_ASSERT(sc);

        status = status ? (scifp->if_flags & flag) : 0;
        /* Now "status" contains the flag value or 0 */

        /*
         * See if recorded ports status is different from what
         * we want it to be.  If it is, flip it.  We record ports
         * status in lp_ifflags so that we won't clear ports flag
         * we haven't set.  In fact, we don't clear or set ports
         * flags directly, but get or release references to them.
         * That's why we can be sure that recorded flags still are
         * in accord with actual ports flags.
         */
        if (status != (lp->lp_ifflags & flag)) {
                error = (*func)(ifp, status);
                if (error)
                        return (error);
                lp->lp_ifflags &= ~flag;
                lp->lp_ifflags |= status;
        }
        return (0);
}

/*
 * Handle IFF_* flags that require certain changes on the lagg port
 * if "status" is true, update ports flags respective to the lagg
 * if "status" is false, forcedly clear the flags set on port.
 */
static int
lagg_setflags(struct lagg_port *lp, int status)
{
        int error, i;

        for (i = 0; lagg_pflags[i].flag; i++) {
                error = lagg_setflag(lp, lagg_pflags[i].flag,
                    status, lagg_pflags[i].func);
                if (error)
                        return (error);
        }
        return (0);
}

static int
lagg_transmit_ethernet(struct ifnet *ifp, struct mbuf *m)
{
        struct lagg_softc *sc = (struct lagg_softc *)ifp->if_softc;

        NET_EPOCH_ASSERT();
#if defined(KERN_TLS) || defined(RATELIMIT)
        if (m->m_pkthdr.csum_flags & CSUM_SND_TAG)
                MPASS(m->m_pkthdr.snd_tag->ifp == ifp);
#endif
        /* We need at least one port */
        if (sc->sc_count == 0) {
                m_freem(m);
                if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
                return (ENXIO);
        }

        ETHER_BPF_MTAP(ifp, m);

        return (lagg_proto_start(sc, m));
}

static int
lagg_transmit_infiniband(struct ifnet *ifp, struct mbuf *m)
{
        struct lagg_softc *sc = (struct lagg_softc *)ifp->if_softc;

        NET_EPOCH_ASSERT();
#if defined(KERN_TLS) || defined(RATELIMIT)
        if (m->m_pkthdr.csum_flags & CSUM_SND_TAG)
                MPASS(m->m_pkthdr.snd_tag->ifp == ifp);
#endif
        /* We need at least one port */
        if (sc->sc_count == 0) {
                m_freem(m);
                if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
                return (ENXIO);
        }

        infiniband_bpf_mtap(ifp, m);

        return (lagg_proto_start(sc, m));
}

/*
 * The ifp->if_qflush entry point for lagg(4) is no-op.
 */
static void
lagg_qflush(struct ifnet *ifp __unused)
{
}

static struct mbuf *
lagg_input_ethernet(struct ifnet *ifp, struct mbuf *m)
{
        struct lagg_port *lp = ifp->if_lagg;
        struct lagg_softc *sc = lp->lp_softc;
        struct ifnet *scifp = sc->sc_ifp;

        NET_EPOCH_ASSERT();
        if ((scifp->if_drv_flags & IFF_DRV_RUNNING) == 0 ||
            lp->lp_detaching != 0) {
                m_freem(m);
                return (NULL);
        }

        m = lagg_proto_input(sc, lp, m);
        if (m != NULL) {
                ETHER_BPF_MTAP(scifp, m);

                if ((scifp->if_flags & IFF_MONITOR) != 0) {
                        m_freem(m);
                        m = NULL;
                }
        }

#ifdef DEV_NETMAP
        if (m != NULL && scifp->if_capenable & IFCAP_NETMAP) {
                scifp->if_input(scifp, m);
                m = NULL;
        }
#endif  /* DEV_NETMAP */

        return (m);
}

static struct mbuf *
lagg_input_infiniband(struct ifnet *ifp, struct mbuf *m)
{
        struct lagg_port *lp = ifp->if_lagg;
        struct lagg_softc *sc = lp->lp_softc;
        struct ifnet *scifp = sc->sc_ifp;

        NET_EPOCH_ASSERT();
        if ((scifp->if_drv_flags & IFF_DRV_RUNNING) == 0 ||
            lp->lp_detaching != 0) {
                m_freem(m);
                return (NULL);
        }

        m = lagg_proto_input(sc, lp, m);
        if (m != NULL) {
                infiniband_bpf_mtap(scifp, m);

                if ((scifp->if_flags & IFF_MONITOR) != 0) {
                        m_freem(m);
                        m = NULL;
                }
        }

        return (m);
}

static int
lagg_media_change(struct ifnet *ifp)
{
        struct lagg_softc *sc = (struct lagg_softc *)ifp->if_softc;

        if (sc->sc_ifflags & IFF_DEBUG)
                printf("%s\n", __func__);

        /* Ignore */
        return (0);
}

static void
lagg_media_status(struct ifnet *ifp, struct ifmediareq *imr)
{
        struct epoch_tracker et;
        struct lagg_softc *sc = (struct lagg_softc *)ifp->if_softc;
        struct lagg_port *lp;

        imr->ifm_status = IFM_AVALID;
        imr->ifm_active = IFM_ETHER | IFM_AUTO;

        NET_EPOCH_ENTER(et);
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                if (LAGG_PORTACTIVE(lp))
                        imr->ifm_status |= IFM_ACTIVE;
        }
        NET_EPOCH_EXIT(et);
}

static void
lagg_linkstate(struct lagg_softc *sc)
{
        struct epoch_tracker et;
        struct lagg_port *lp;
        int new_link = LINK_STATE_DOWN;
        uint64_t speed;

        LAGG_XLOCK_ASSERT(sc);

        /* LACP handles link state itself */
        if (sc->sc_proto == LAGG_PROTO_LACP)
                return;

        /* Our link is considered up if at least one of our ports is active */
        NET_EPOCH_ENTER(et);
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                if (lp->lp_ifp->if_link_state == LINK_STATE_UP) {
                        new_link = LINK_STATE_UP;
                        break;
                }
        }
        NET_EPOCH_EXIT(et);
        if_link_state_change(sc->sc_ifp, new_link);

        /* Update if_baudrate to reflect the max possible speed */
        switch (sc->sc_proto) {
                case LAGG_PROTO_FAILOVER:
                        sc->sc_ifp->if_baudrate = sc->sc_primary != NULL ?
                            sc->sc_primary->lp_ifp->if_baudrate : 0;
                        break;
                case LAGG_PROTO_ROUNDROBIN:
                case LAGG_PROTO_LOADBALANCE:
                case LAGG_PROTO_BROADCAST:
                        speed = 0;
                        NET_EPOCH_ENTER(et);
                        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries)
                                speed += lp->lp_ifp->if_baudrate;
                        NET_EPOCH_EXIT(et);
                        sc->sc_ifp->if_baudrate = speed;
                        break;
                case LAGG_PROTO_LACP:
                        /* LACP updates if_baudrate itself */
                        break;
        }
}

static void
lagg_port_state(struct ifnet *ifp, int state)
{
        struct lagg_port *lp = (struct lagg_port *)ifp->if_lagg;
        struct lagg_softc *sc = NULL;

        if (lp != NULL)
                sc = lp->lp_softc;
        if (sc == NULL)
                return;

        LAGG_XLOCK(sc);
        lagg_linkstate(sc);
        lagg_proto_linkstate(sc, lp);
        LAGG_XUNLOCK(sc);
}

static struct lagg_port *
lagg_link_active(struct lagg_softc *sc, struct lagg_port *lp)
{
        struct lagg_port *lp_next, *rval = NULL;

        /*
         * Search a port which reports an active link state.
         */

#ifdef INVARIANTS
        /*
         * This is called with either in the network epoch
         * or with LAGG_XLOCK(sc) held.
         */
        if (!in_epoch(net_epoch_preempt))
                LAGG_XLOCK_ASSERT(sc);
#endif

        if (lp == NULL)
                goto search;
        if (LAGG_PORTACTIVE(lp)) {
                rval = lp;
                goto found;
        }
        if ((lp_next = CK_SLIST_NEXT(lp, lp_entries)) != NULL &&
            LAGG_PORTACTIVE(lp_next)) {
                rval = lp_next;
                goto found;
        }

search:
        CK_SLIST_FOREACH(lp_next, &sc->sc_ports, lp_entries) {
                if (LAGG_PORTACTIVE(lp_next)) {
                        return (lp_next);
                }
        }
found:
        return (rval);
}

int
lagg_enqueue(struct ifnet *ifp, struct mbuf *m)
{

#if defined(KERN_TLS) || defined(RATELIMIT)
        if (m->m_pkthdr.csum_flags & CSUM_SND_TAG) {
                struct lagg_snd_tag *lst;
                struct m_snd_tag *mst;

                mst = m->m_pkthdr.snd_tag;
                lst = mst_to_lst(mst);
                if (lst->tag->ifp != ifp) {
                        m_freem(m);
                        return (EAGAIN);
                }
                m->m_pkthdr.snd_tag = m_snd_tag_ref(lst->tag);
                m_snd_tag_rele(mst);
        }
#endif
        return (ifp->if_transmit)(ifp, m);
}

/*
 * No proto
 */
static int
lagg_none_start(struct lagg_softc *sc, struct mbuf *m)
{
        m_freem(m);
        if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, 1);
        /* No active ports available */
        return (ENETDOWN);
}

static struct mbuf *
lagg_none_input(struct lagg_softc *sc, struct lagg_port *lp, struct mbuf *m)
{
        m_freem(m);
        return (NULL);
}

/*
 * Simple round robin aggregation
 */
static void
lagg_rr_attach(struct lagg_softc *sc)
{
        sc->sc_seq = 0;
        sc->sc_stride = 1;
}

static int
lagg_rr_start(struct lagg_softc *sc, struct mbuf *m)
{
        struct lagg_port *lp;
        uint32_t p;

        p = atomic_fetchadd_32(&sc->sc_seq, 1);
        p /= sc->sc_stride;
        p %= sc->sc_count;
        lp = CK_SLIST_FIRST(&sc->sc_ports);

        while (p--)
                lp = CK_SLIST_NEXT(lp, lp_entries);

        /*
         * Check the port's link state. This will return the next active
         * port if the link is down or the port is NULL.
         */
        if ((lp = lagg_link_active(sc, lp)) == NULL) {
                if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, 1);
                m_freem(m);
                return (ENETDOWN);
        }

        /* Send mbuf */
        return (lagg_enqueue(lp->lp_ifp, m));
}

/*
 * Broadcast mode
 */
static int
lagg_bcast_start(struct lagg_softc *sc, struct mbuf *m)
{
        int errors = 0;
        int ret;
        struct lagg_port *lp, *last = NULL;
        struct mbuf *m0;

        NET_EPOCH_ASSERT();
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
                if (!LAGG_PORTACTIVE(lp))
                        continue;

                if (last != NULL) {
                        m0 = m_copym(m, 0, M_COPYALL, M_NOWAIT);
                        if (m0 == NULL) {
                                ret = ENOBUFS;
                                errors++;
                                break;
                        }
                        lagg_enqueue(last->lp_ifp, m0);
                }
                last = lp;
        }

        if (last == NULL) {
                if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, 1);
                m_freem(m);
                return (ENOENT);
        }
        if ((last = lagg_link_active(sc, last)) == NULL) {
                errors++;
                if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, errors);
                m_freem(m);
                return (ENETDOWN);
        }

        ret = lagg_enqueue(last->lp_ifp, m);
        if (errors != 0)
                if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, errors);

        return (ret);
}

/*
 * Active failover
 */
static int
lagg_fail_start(struct lagg_softc *sc, struct mbuf *m)
{
        struct lagg_port *lp;

        /* Use the master port if active or the next available port */
        if ((lp = lagg_link_active(sc, sc->sc_primary)) == NULL) {
                if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, 1);
                m_freem(m);
                return (ENETDOWN);
        }

        /* Send mbuf */
        return (lagg_enqueue(lp->lp_ifp, m));
}

static struct mbuf *
lagg_fail_input(struct lagg_softc *sc, struct lagg_port *lp, struct mbuf *m)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct lagg_port *tmp_tp;

        if (lp == sc->sc_primary || V_lagg_failover_rx_all) {
                m->m_pkthdr.rcvif = ifp;
                return (m);
        }

        if (!LAGG_PORTACTIVE(sc->sc_primary)) {
                tmp_tp = lagg_link_active(sc, sc->sc_primary);
                /*
                 * If tmp_tp is null, we've received a packet when all
                 * our links are down. Weird, but process it anyways.
                 */
                if (tmp_tp == NULL || tmp_tp == lp) {
                        m->m_pkthdr.rcvif = ifp;
                        return (m);
                }
        }

        m_freem(m);
        return (NULL);
}

/*
 * Loadbalancing
 */
static void
lagg_lb_attach(struct lagg_softc *sc)
{
        struct lagg_port *lp;
        struct lagg_lb *lb;

        LAGG_XLOCK_ASSERT(sc);
        lb = malloc(sizeof(struct lagg_lb), M_LAGG, M_WAITOK | M_ZERO);
        lb->lb_key = m_ether_tcpip_hash_init();
        sc->sc_psc = lb;

        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries)
                lagg_lb_port_create(lp);
}

static void
lagg_lb_detach(struct lagg_softc *sc)
{
        struct lagg_lb *lb;

        lb = (struct lagg_lb *)sc->sc_psc;
        if (lb != NULL)
                free(lb, M_LAGG);
}

static int
lagg_lb_porttable(struct lagg_softc *sc, struct lagg_port *lp)
{
        struct lagg_lb *lb = (struct lagg_lb *)sc->sc_psc;
        struct lagg_port *lp_next;
        int i = 0, rv;

        rv = 0;
        bzero(&lb->lb_ports, sizeof(lb->lb_ports));
        LAGG_XLOCK_ASSERT(sc);
        CK_SLIST_FOREACH(lp_next, &sc->sc_ports, lp_entries) {
                if (lp_next == lp)
                        continue;
                if (i >= LAGG_MAX_PORTS) {
                        rv = EINVAL;
                        break;
                }
                if (sc->sc_ifflags & IFF_DEBUG)
                        printf("%s: port %s at index %d\n",
                            sc->sc_ifname, lp_next->lp_ifp->if_xname, i);
                lb->lb_ports[i++] = lp_next;
        }

        return (rv);
}

static int
lagg_lb_port_create(struct lagg_port *lp)
{
        struct lagg_softc *sc = lp->lp_softc;
        return (lagg_lb_porttable(sc, NULL));
}

static void
lagg_lb_port_destroy(struct lagg_port *lp)
{
        struct lagg_softc *sc = lp->lp_softc;
        lagg_lb_porttable(sc, lp);
}

static int
lagg_lb_start(struct lagg_softc *sc, struct mbuf *m)
{
        struct lagg_lb *lb = (struct lagg_lb *)sc->sc_psc;
        struct lagg_port *lp = NULL;
        uint32_t p = 0;

        if ((sc->sc_opts & LAGG_OPT_USE_FLOWID) &&
            M_HASHTYPE_GET(m) != M_HASHTYPE_NONE)
                p = m->m_pkthdr.flowid >> sc->flowid_shift;
        else
                p = m_ether_tcpip_hash(sc->sc_flags, m, lb->lb_key);
        p %= sc->sc_count;
        lp = lb->lb_ports[p];

        /*
         * Check the port's link state. This will return the next active
         * port if the link is down or the port is NULL.
         */
        if ((lp = lagg_link_active(sc, lp)) == NULL) {
                if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, 1);
                m_freem(m);
                return (ENETDOWN);
        }

        /* Send mbuf */
        return (lagg_enqueue(lp->lp_ifp, m));
}

/*
 * 802.3ad LACP
 */
static void
lagg_lacp_attach(struct lagg_softc *sc)
{
        struct lagg_port *lp;

        lacp_attach(sc);
        LAGG_XLOCK_ASSERT(sc);
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries)
                lacp_port_create(lp);
}

static void
lagg_lacp_detach(struct lagg_softc *sc)
{
        struct lagg_port *lp;
        void *psc;

        LAGG_XLOCK_ASSERT(sc);
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries)
                lacp_port_destroy(lp);

        psc = sc->sc_psc;
        sc->sc_psc = NULL;
        lacp_detach(psc);
}

static void
lagg_lacp_lladdr(struct lagg_softc *sc)
{
        struct lagg_port *lp;

        LAGG_SXLOCK_ASSERT(sc);

        /* purge all the lacp ports */
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries)
                lacp_port_destroy(lp);

        /* add them back in */
        CK_SLIST_FOREACH(lp, &sc->sc_ports, lp_entries)
                lacp_port_create(lp);
}

static int
lagg_lacp_start(struct lagg_softc *sc, struct mbuf *m)
{
        struct lagg_port *lp;
        int err;

        lp = lacp_select_tx_port(sc, m, &err);
        if (lp == NULL) {
                if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, 1);
                m_freem(m);
                return (err);
        }

        /* Send mbuf */
        return (lagg_enqueue(lp->lp_ifp, m));
}

static struct mbuf *
lagg_lacp_input(struct lagg_softc *sc, struct lagg_port *lp, struct mbuf *m)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ether_header *eh;
        u_short etype;

        eh = mtod(m, struct ether_header *);
        etype = ntohs(eh->ether_type);

        /* Tap off LACP control messages */
        if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_SLOW) {
                m = lacp_input(lp, m);
                if (m == NULL)
                        return (NULL);
        }

        /*
         * If the port is not collecting or not in the active aggregator then
         * free and return.
         */
        if (!lacp_iscollecting(lp) || !lacp_isactive(lp)) {
                m_freem(m);
                return (NULL);
        }

        m->m_pkthdr.rcvif = ifp;
        return (m);
}

/* Default input */
static struct mbuf *
lagg_default_input(struct lagg_softc *sc, struct lagg_port *lp, struct mbuf *m)
{
        struct ifnet *ifp = sc->sc_ifp;

        /* Just pass in the packet to our lagg device */
        m->m_pkthdr.rcvif = ifp;

        return (m);
}