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FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //sys/net/if_epair.c |
/*-
* Copyright (c) 2008 The FreeBSD Foundation
* Copyright (c) 2009-2010 Bjoern A. Zeeb <bz@FreeBSD.org>
* All rights reserved.
*
* This software was developed by CK Software GmbH under sponsorship
* from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* A pair of virtual back-to-back connected ethernet like interfaces
* (``two interfaces with a virtual cross-over cable'').
*
* This is mostly intended to be used to provide connectivity between
* different virtual network stack instances.
*/
/*
* Things to re-think once we have more experience:
* - ifp->if_reassign function once we can test with vimage. Depending on
* how if_vmove() is going to be improved.
* - Real random etheraddrs that are checked to be uniquish; we would need
* to re-do them in case we move the interface between network stacks
* in a private if_reassign function.
* In case we bridge to a real interface/network or between indepedent
* epairs on multiple stacks/machines, we may need this.
* For now let the user handle that case.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/sys/net/if_epair.c 222247 2011-05-24 08:02:55Z zec $");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/module.h>
#include <sys/refcount.h>
#include <sys/queue.h>
#include <sys/smp.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/types.h>
#include <net/bpf.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_clone.h>
#include <net/if_media.h>
#include <net/if_var.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/vnet.h>
#define EPAIRNAME "epair"
SYSCTL_DECL(_net_link);
SYSCTL_NODE(_net_link, OID_AUTO, epair, CTLFLAG_RW, 0, "epair sysctl");
#ifdef EPAIR_DEBUG
static int epair_debug = 0;
SYSCTL_INT(_net_link_epair, OID_AUTO, epair_debug, CTLFLAG_RW,
&epair_debug, 0, "if_epair(4) debugging.");
#define DPRINTF(fmt, arg...) \
if (epair_debug) \
printf("[%s:%d] " fmt, __func__, __LINE__, ##arg)
#else
#define DPRINTF(fmt, arg...)
#endif
static void epair_nh_sintr(struct mbuf *);
static struct mbuf *epair_nh_m2cpuid(struct mbuf *, uintptr_t, u_int *);
static void epair_nh_drainedcpu(u_int);
static void epair_start_locked(struct ifnet *);
static int epair_media_change(struct ifnet *);
static void epair_media_status(struct ifnet *, struct ifmediareq *);
static int epair_clone_match(struct if_clone *, const char *);
static int epair_clone_create(struct if_clone *, char *, size_t, caddr_t);
static int epair_clone_destroy(struct if_clone *, struct ifnet *);
/* Netisr realted definitions and sysctl. */
static struct netisr_handler epair_nh = {
.nh_name = EPAIRNAME,
.nh_proto = NETISR_EPAIR,
.nh_policy = NETISR_POLICY_CPU,
.nh_handler = epair_nh_sintr,
.nh_m2cpuid = epair_nh_m2cpuid,
.nh_drainedcpu = epair_nh_drainedcpu,
};
static int
sysctl_epair_netisr_maxqlen(SYSCTL_HANDLER_ARGS)
{
int error, qlimit;
netisr_getqlimit(&epair_nh, &qlimit);
error = sysctl_handle_int(oidp, &qlimit, 0, req);
if (error || !req->newptr)
return (error);
if (qlimit < 1)
return (EINVAL);
return (netisr_setqlimit(&epair_nh, qlimit));
}
SYSCTL_PROC(_net_link_epair, OID_AUTO, netisr_maxqlen, CTLTYPE_INT|CTLFLAG_RW,
0, 0, sysctl_epair_netisr_maxqlen, "I",
"Maximum if_epair(4) netisr \"hw\" queue length");
struct epair_softc {
struct ifnet *ifp; /* This ifp. */
struct ifnet *oifp; /* other ifp of pair. */
struct ifmedia media; /* Media config (fake). */
u_int refcount; /* # of mbufs in flight. */
u_int cpuid; /* CPU ID assigned upon creation. */
void (*if_qflush)(struct ifnet *);
/* Original if_qflush routine. */
};
/*
* Per-CPU list of ifps with data in the ifq that needs to be flushed
* to the netisr ``hw'' queue before we allow any further direct queuing
* to the ``hw'' queue.
*/
struct epair_ifp_drain {
STAILQ_ENTRY(epair_ifp_drain) ifp_next;
struct ifnet *ifp;
};
STAILQ_HEAD(eid_list, epair_ifp_drain);
#define EPAIR_LOCK_INIT(dpcpu) mtx_init(&(dpcpu)->if_epair_mtx, \
"if_epair", NULL, MTX_DEF)
#define EPAIR_LOCK_DESTROY(dpcpu) mtx_destroy(&(dpcpu)->if_epair_mtx)
#define EPAIR_LOCK_ASSERT(dpcpu) mtx_assert(&(dpcpu)->if_epair_mtx, \
MA_OWNED)
#define EPAIR_LOCK(dpcpu) mtx_lock(&(dpcpu)->if_epair_mtx)
#define EPAIR_UNLOCK(dpcpu) mtx_unlock(&(dpcpu)->if_epair_mtx)
#ifdef INVARIANTS
#define EPAIR_REFCOUNT_INIT(r, v) refcount_init((r), (v))
#define EPAIR_REFCOUNT_AQUIRE(r) refcount_acquire((r))
#define EPAIR_REFCOUNT_RELEASE(r) refcount_release((r))
#define EPAIR_REFCOUNT_ASSERT(a, p) KASSERT(a, p)
#else
#define EPAIR_REFCOUNT_INIT(r, v)
#define EPAIR_REFCOUNT_AQUIRE(r)
#define EPAIR_REFCOUNT_RELEASE(r)
#define EPAIR_REFCOUNT_ASSERT(a, p)
#endif
static MALLOC_DEFINE(M_EPAIR, EPAIRNAME,
"Pair of virtual cross-over connected Ethernet-like interfaces");
static struct if_clone epair_cloner = IFC_CLONE_INITIALIZER(
EPAIRNAME, NULL, IF_MAXUNIT,
NULL, epair_clone_match, epair_clone_create, epair_clone_destroy);
/*
* DPCPU area and functions.
*/
struct epair_dpcpu {
struct mtx if_epair_mtx; /* Per-CPU locking. */
int epair_drv_flags; /* Per-CPU ``hw'' drv flags. */
struct eid_list epair_ifp_drain_list; /* Per-CPU list of ifps with
* data in the ifq. */
};
DPCPU_DEFINE(struct epair_dpcpu, epair_dpcpu);
static void
epair_dpcpu_init(void)
{
struct epair_dpcpu *epair_dpcpu;
struct eid_list *s;
u_int cpuid;
CPU_FOREACH(cpuid) {
epair_dpcpu = DPCPU_ID_PTR(cpuid, epair_dpcpu);
/* Initialize per-cpu lock. */
EPAIR_LOCK_INIT(epair_dpcpu);
/* Driver flags are per-cpu as are our netisr "hw" queues. */
epair_dpcpu->epair_drv_flags = 0;
/*
* Initialize per-cpu drain list.
* Manually do what STAILQ_HEAD_INITIALIZER would do.
*/
s = &epair_dpcpu->epair_ifp_drain_list;
s->stqh_first = NULL;
s->stqh_last = &s->stqh_first;
}
}
static void
epair_dpcpu_detach(void)
{
struct epair_dpcpu *epair_dpcpu;
u_int cpuid;
CPU_FOREACH(cpuid) {
epair_dpcpu = DPCPU_ID_PTR(cpuid, epair_dpcpu);
/* Destroy per-cpu lock. */
EPAIR_LOCK_DESTROY(epair_dpcpu);
}
}
/*
* Helper functions.
*/
static u_int
cpuid_from_ifp(struct ifnet *ifp)
{
struct epair_softc *sc;
if (ifp == NULL)
return (0);
sc = ifp->if_softc;
return (sc->cpuid);
}
/*
* Netisr handler functions.
*/
static void
epair_nh_sintr(struct mbuf *m)
{
struct ifnet *ifp;
struct epair_softc *sc;
ifp = m->m_pkthdr.rcvif;
(*ifp->if_input)(ifp, m);
sc = ifp->if_softc;
EPAIR_REFCOUNT_RELEASE(&sc->refcount);
EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1,
("%s: ifp=%p sc->refcount not >= 1: %d",
__func__, ifp, sc->refcount));
DPRINTF("ifp=%p refcount=%u\n", ifp, sc->refcount);
}
static struct mbuf *
epair_nh_m2cpuid(struct mbuf *m, uintptr_t source, u_int *cpuid)
{
*cpuid = cpuid_from_ifp(m->m_pkthdr.rcvif);
return (m);
}
static void
epair_nh_drainedcpu(u_int cpuid)
{
struct epair_dpcpu *epair_dpcpu;
struct epair_ifp_drain *elm, *tvar;
struct ifnet *ifp;
epair_dpcpu = DPCPU_ID_PTR(cpuid, epair_dpcpu);
EPAIR_LOCK(epair_dpcpu);
/*
* Assume our "hw" queue and possibly ifq will be emptied
* again. In case we will overflow the "hw" queue while
* draining, epair_start_locked will set IFF_DRV_OACTIVE
* again and we will stop and return.
*/
STAILQ_FOREACH_SAFE(elm, &epair_dpcpu->epair_ifp_drain_list,
ifp_next, tvar) {
ifp = elm->ifp;
epair_dpcpu->epair_drv_flags &= ~IFF_DRV_OACTIVE;
ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
epair_start_locked(ifp);
IFQ_LOCK(&ifp->if_snd);
if (IFQ_IS_EMPTY(&ifp->if_snd)) {
struct epair_softc *sc;
STAILQ_REMOVE(&epair_dpcpu->epair_ifp_drain_list,
elm, epair_ifp_drain, ifp_next);
/* The cached ifp goes off the list. */
sc = ifp->if_softc;
EPAIR_REFCOUNT_RELEASE(&sc->refcount);
EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1,
("%s: ifp=%p sc->refcount not >= 1: %d",
__func__, ifp, sc->refcount));
free(elm, M_EPAIR);
}
IFQ_UNLOCK(&ifp->if_snd);
if ((ifp->if_drv_flags & IFF_DRV_OACTIVE) != 0) {
/* Our "hw"q overflew again. */
epair_dpcpu->epair_drv_flags |= IFF_DRV_OACTIVE;
DPRINTF("hw queue length overflow at %u\n",
epair_nh.nh_qlimit);
break;
}
}
EPAIR_UNLOCK(epair_dpcpu);
}
/*
* Network interface (`if') related functions.
*/
static void
epair_remove_ifp_from_draining(struct ifnet *ifp)
{
struct epair_dpcpu *epair_dpcpu;
struct epair_ifp_drain *elm, *tvar;
u_int cpuid;
CPU_FOREACH(cpuid) {
epair_dpcpu = DPCPU_ID_PTR(cpuid, epair_dpcpu);
EPAIR_LOCK(epair_dpcpu);
STAILQ_FOREACH_SAFE(elm, &epair_dpcpu->epair_ifp_drain_list,
ifp_next, tvar) {
if (ifp == elm->ifp) {
struct epair_softc *sc;
STAILQ_REMOVE(
&epair_dpcpu->epair_ifp_drain_list, elm,
epair_ifp_drain, ifp_next);
/* The cached ifp goes off the list. */
sc = ifp->if_softc;
EPAIR_REFCOUNT_RELEASE(&sc->refcount);
EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1,
("%s: ifp=%p sc->refcount not >= 1: %d",
__func__, ifp, sc->refcount));
free(elm, M_EPAIR);
}
}
EPAIR_UNLOCK(epair_dpcpu);
}
}
static int
epair_add_ifp_for_draining(struct ifnet *ifp)
{
struct epair_dpcpu *epair_dpcpu;
struct epair_softc *sc;
struct epair_ifp_drain *elm = NULL;
sc = ifp->if_softc;
epair_dpcpu = DPCPU_ID_PTR(sc->cpuid, epair_dpcpu);
EPAIR_LOCK_ASSERT(epair_dpcpu);
STAILQ_FOREACH(elm, &epair_dpcpu->epair_ifp_drain_list, ifp_next)
if (elm->ifp == ifp)
break;
/* If the ifp is there already, return success. */
if (elm != NULL)
return (0);
elm = malloc(sizeof(struct epair_ifp_drain), M_EPAIR, M_NOWAIT|M_ZERO);
if (elm == NULL)
return (ENOMEM);
elm->ifp = ifp;
/* Add a reference for the ifp pointer on the list. */
EPAIR_REFCOUNT_AQUIRE(&sc->refcount);
STAILQ_INSERT_TAIL(&epair_dpcpu->epair_ifp_drain_list, elm, ifp_next);
return (0);
}
static void
epair_start_locked(struct ifnet *ifp)
{
struct epair_dpcpu *epair_dpcpu;
struct mbuf *m;
struct epair_softc *sc;
struct ifnet *oifp;
int error;
DPRINTF("ifp=%p\n", ifp);
sc = ifp->if_softc;
epair_dpcpu = DPCPU_ID_PTR(sc->cpuid, epair_dpcpu);
EPAIR_LOCK_ASSERT(epair_dpcpu);
if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
return;
if ((ifp->if_flags & IFF_UP) == 0)
return;
/*
* We get patckets here from ether_output via if_handoff()
* and ned to put them into the input queue of the oifp
* and call oifp->if_input() via netisr/epair_sintr().
*/
oifp = sc->oifp;
sc = oifp->if_softc;
for (;;) {
IFQ_DEQUEUE(&ifp->if_snd, m);
if (m == NULL)
break;
BPF_MTAP(ifp, m);
/*
* In case the outgoing interface is not usable,
* drop the packet.
*/
if ((oifp->if_drv_flags & IFF_DRV_RUNNING) == 0 ||
(oifp->if_flags & IFF_UP) ==0) {
ifp->if_oerrors++;
m_freem(m);
continue;
}
DPRINTF("packet %s -> %s\n", ifp->if_xname, oifp->if_xname);
/*
* Add a reference so the interface cannot go while the
* packet is in transit as we rely on rcvif to stay valid.
*/
EPAIR_REFCOUNT_AQUIRE(&sc->refcount);
m->m_pkthdr.rcvif = oifp;
CURVNET_SET_QUIET(oifp->if_vnet);
error = netisr_queue(NETISR_EPAIR, m);
CURVNET_RESTORE();
if (!error) {
ifp->if_opackets++;
/* Someone else received the packet. */
oifp->if_ipackets++;
} else {
/* The packet was freed already. */
epair_dpcpu->epair_drv_flags |= IFF_DRV_OACTIVE;
ifp->if_drv_flags |= IFF_DRV_OACTIVE;
(void) epair_add_ifp_for_draining(ifp);
ifp->if_oerrors++;
EPAIR_REFCOUNT_RELEASE(&sc->refcount);
EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1,
("%s: ifp=%p sc->refcount not >= 1: %d",
__func__, oifp, sc->refcount));
}
}
}
static void
epair_start(struct ifnet *ifp)
{
struct epair_dpcpu *epair_dpcpu;
epair_dpcpu = DPCPU_ID_PTR(cpuid_from_ifp(ifp), epair_dpcpu);
EPAIR_LOCK(epair_dpcpu);
epair_start_locked(ifp);
EPAIR_UNLOCK(epair_dpcpu);
}
static int
epair_transmit_locked(struct ifnet *ifp, struct mbuf *m)
{
struct epair_dpcpu *epair_dpcpu;
struct epair_softc *sc;
struct ifnet *oifp;
int error, len;
short mflags;
DPRINTF("ifp=%p m=%p\n", ifp, m);
sc = ifp->if_softc;
epair_dpcpu = DPCPU_ID_PTR(sc->cpuid, epair_dpcpu);
EPAIR_LOCK_ASSERT(epair_dpcpu);
if (m == NULL)
return (0);
/*
* We are not going to use the interface en/dequeue mechanism
* on the TX side. We are called from ether_output_frame()
* and will put the packet into the incoming queue of the
* other interface of our pair via the netsir.
*/
if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
m_freem(m);
return (ENXIO);
}
if ((ifp->if_flags & IFF_UP) == 0) {
m_freem(m);
return (ENETDOWN);
}
BPF_MTAP(ifp, m);
/*
* In case the outgoing interface is not usable,
* drop the packet.
*/
oifp = sc->oifp;
if ((oifp->if_drv_flags & IFF_DRV_RUNNING) == 0 ||
(oifp->if_flags & IFF_UP) ==0) {
ifp->if_oerrors++;
m_freem(m);
return (0);
}
len = m->m_pkthdr.len;
mflags = m->m_flags;
DPRINTF("packet %s -> %s\n", ifp->if_xname, oifp->if_xname);
#ifdef ALTQ
/* Support ALTQ via the clasic if_start() path. */
IF_LOCK(&ifp->if_snd);
if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
ALTQ_ENQUEUE(&ifp->if_snd, m, NULL, error);
if (error)
ifp->if_snd.ifq_drops++;
IF_UNLOCK(&ifp->if_snd);
if (!error) {
ifp->if_obytes += len;
if (mflags & (M_BCAST|M_MCAST))
ifp->if_omcasts++;
if ((ifp->if_drv_flags & IFF_DRV_OACTIVE) == 0)
epair_start_locked(ifp);
else
(void)epair_add_ifp_for_draining(ifp);
}
return (error);
}
IF_UNLOCK(&ifp->if_snd);
#endif
if ((epair_dpcpu->epair_drv_flags & IFF_DRV_OACTIVE) != 0) {
/*
* Our hardware queue is full, try to fall back
* queuing to the ifq but do not call ifp->if_start.
* Either we are lucky or the packet is gone.
*/
IFQ_ENQUEUE(&ifp->if_snd, m, error);
if (!error)
(void)epair_add_ifp_for_draining(ifp);
return (error);
}
sc = oifp->if_softc;
/*
* Add a reference so the interface cannot go while the
* packet is in transit as we rely on rcvif to stay valid.
*/
EPAIR_REFCOUNT_AQUIRE(&sc->refcount);
m->m_pkthdr.rcvif = oifp;
CURVNET_SET_QUIET(oifp->if_vnet);
error = netisr_queue(NETISR_EPAIR, m);
CURVNET_RESTORE();
if (!error) {
ifp->if_opackets++;
/*
* IFQ_HANDOFF_ADJ/ip_handoff() update statistics,
* but as we bypass all this we have to duplicate
* the logic another time.
*/
ifp->if_obytes += len;
if (mflags & (M_BCAST|M_MCAST))
ifp->if_omcasts++;
/* Someone else received the packet. */
oifp->if_ipackets++;
} else {
/* The packet was freed already. */
epair_dpcpu->epair_drv_flags |= IFF_DRV_OACTIVE;
ifp->if_drv_flags |= IFF_DRV_OACTIVE;
ifp->if_oerrors++;
EPAIR_REFCOUNT_RELEASE(&sc->refcount);
EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1,
("%s: ifp=%p sc->refcount not >= 1: %d",
__func__, oifp, sc->refcount));
}
return (error);
}
static int
epair_transmit(struct ifnet *ifp, struct mbuf *m)
{
struct epair_dpcpu *epair_dpcpu;
int error;
epair_dpcpu = DPCPU_ID_PTR(cpuid_from_ifp(ifp), epair_dpcpu);
EPAIR_LOCK(epair_dpcpu);
error = epair_transmit_locked(ifp, m);
EPAIR_UNLOCK(epair_dpcpu);
return (error);
}
static void
epair_qflush(struct ifnet *ifp)
{
struct epair_softc *sc;
sc = ifp->if_softc;
KASSERT(sc != NULL, ("%s: ifp=%p, epair_softc gone? sc=%p\n",
__func__, ifp, sc));
/*
* Remove this ifp from all backpointer lists. The interface will not
* usable for flushing anyway nor should it have anything to flush
* after if_qflush().
*/
epair_remove_ifp_from_draining(ifp);
if (sc->if_qflush)
sc->if_qflush(ifp);
}
static int
epair_media_change(struct ifnet *ifp __unused)
{
/* Do nothing. */
return (0);
}
static void
epair_media_status(struct ifnet *ifp __unused, struct ifmediareq *imr)
{
imr->ifm_status = IFM_AVALID | IFM_ACTIVE;
imr->ifm_active = IFM_ETHER | IFM_10G_T | IFM_FDX;
}
static int
epair_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
struct epair_softc *sc;
struct ifreq *ifr;
int error;
ifr = (struct ifreq *)data;
switch (cmd) {
case SIOCSIFFLAGS:
case SIOCADDMULTI:
case SIOCDELMULTI:
error = 0;
break;
case SIOCSIFMEDIA:
case SIOCGIFMEDIA:
sc = ifp->if_softc;
error = ifmedia_ioctl(ifp, ifr, &sc->media, cmd);
break;
case SIOCSIFMTU:
/* We basically allow all kinds of MTUs. */
ifp->if_mtu = ifr->ifr_mtu;
error = 0;
break;
default:
/* Let the common ethernet handler process this. */
error = ether_ioctl(ifp, cmd, data);
break;
}
return (error);
}
static void
epair_init(void *dummy __unused)
{
}
/*
* Interface cloning functions.
* We use our private ones so that we can create/destroy our secondary
* device along with the primary one.
*/
static int
epair_clone_match(struct if_clone *ifc, const char *name)
{
const char *cp;
DPRINTF("name='%s'\n", name);
/*
* Our base name is epair.
* Our interfaces will be named epair<n>[ab].
* So accept anything of the following list:
* - epair
* - epair<n>
* but not the epair<n>[ab] versions.
*/
if (strncmp(EPAIRNAME, name, sizeof(EPAIRNAME)-1) != 0)
return (0);
for (cp = name + sizeof(EPAIRNAME) - 1; *cp != '\0'; cp++) {
if (*cp < '0' || *cp > '9')
return (0);
}
return (1);
}
static int
epair_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
{
struct epair_softc *sca, *scb;
struct ifnet *ifp;
char *dp;
int error, unit, wildcard;
uint8_t eaddr[ETHER_ADDR_LEN]; /* 00:00:00:00:00:00 */
/*
* We are abusing params to create our second interface.
* Actually we already created it and called if_clone_createif()
* for it to do the official insertion procedure the moment we knew
* it cannot fail anymore. So just do attach it here.
*/
if (params) {
scb = (struct epair_softc *)params;
ifp = scb->ifp;
/* Assign a hopefully unique, locally administered etheraddr. */
eaddr[0] = 0x02;
eaddr[3] = (ifp->if_index >> 8) & 0xff;
eaddr[4] = ifp->if_index & 0xff;
eaddr[5] = 0x0b;
ether_ifattach(ifp, eaddr);
/* Correctly set the name for the cloner list. */
strlcpy(name, scb->ifp->if_xname, len);
return (0);
}
/* Try to see if a special unit was requested. */
error = ifc_name2unit(name, &unit);
if (error != 0)
return (error);
wildcard = (unit < 0);
error = ifc_alloc_unit(ifc, &unit);
if (error != 0)
return (error);
/*
* If no unit had been given, we need to adjust the ifName.
* Also make sure there is space for our extra [ab] suffix.
*/
for (dp = name; *dp != '\0'; dp++);
if (wildcard) {
error = snprintf(dp, len - (dp - name), "%d", unit);
if (error > len - (dp - name) - 1) {
/* ifName too long. */
ifc_free_unit(ifc, unit);
return (ENOSPC);
}
dp += error;
}
if (len - (dp - name) - 1 < 1) {
/* No space left for our [ab] suffix. */
ifc_free_unit(ifc, unit);
return (ENOSPC);
}
*dp = 'a';
/* Must not change dp so we can replace 'a' by 'b' later. */
*(dp+1) = '\0';
/* Allocate memory for both [ab] interfaces */
sca = malloc(sizeof(struct epair_softc), M_EPAIR, M_WAITOK | M_ZERO);
EPAIR_REFCOUNT_INIT(&sca->refcount, 1);
sca->ifp = if_alloc(IFT_ETHER);
if (sca->ifp == NULL) {
free(sca, M_EPAIR);
ifc_free_unit(ifc, unit);
return (ENOSPC);
}
scb = malloc(sizeof(struct epair_softc), M_EPAIR, M_WAITOK | M_ZERO);
EPAIR_REFCOUNT_INIT(&scb->refcount, 1);
scb->ifp = if_alloc(IFT_ETHER);
if (scb->ifp == NULL) {
free(scb, M_EPAIR);
if_free(sca->ifp);
free(sca, M_EPAIR);
ifc_free_unit(ifc, unit);
return (ENOSPC);
}
/*
* Cross-reference the interfaces so we will be able to free both.
*/
sca->oifp = scb->ifp;
scb->oifp = sca->ifp;
/*
* Calculate the cpuid for netisr queueing based on the
* ifIndex of the interfaces. As long as we cannot configure
* this or use cpuset information easily we cannot guarantee
* cache locality but we can at least allow parallelism.
*/
sca->cpuid =
netisr_get_cpuid(sca->ifp->if_index % netisr_get_cpucount());
scb->cpuid =
netisr_get_cpuid(scb->ifp->if_index % netisr_get_cpucount());
/* Finish initialization of interface <n>a. */
ifp = sca->ifp;
ifp->if_softc = sca;
strlcpy(ifp->if_xname, name, IFNAMSIZ);
ifp->if_dname = ifc->ifc_name;
ifp->if_dunit = unit;
ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
ifp->if_capabilities = IFCAP_VLAN_MTU;
ifp->if_capenable = IFCAP_VLAN_MTU;
ifp->if_start = epair_start;
ifp->if_ioctl = epair_ioctl;
ifp->if_init = epair_init;
ifp->if_snd.ifq_maxlen = ifqmaxlen;
/* Assign a hopefully unique, locally administered etheraddr. */
eaddr[0] = 0x02;
eaddr[3] = (ifp->if_index >> 8) & 0xff;
eaddr[4] = ifp->if_index & 0xff;
eaddr[5] = 0x0a;
ether_ifattach(ifp, eaddr);
sca->if_qflush = ifp->if_qflush;
ifp->if_qflush = epair_qflush;
ifp->if_transmit = epair_transmit;
ifp->if_baudrate = IF_Gbps(10UL); /* arbitrary maximum */
/* Swap the name and finish initialization of interface <n>b. */
*dp = 'b';
ifp = scb->ifp;
ifp->if_softc = scb;
strlcpy(ifp->if_xname, name, IFNAMSIZ);
ifp->if_dname = ifc->ifc_name;
ifp->if_dunit = unit;
ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
ifp->if_capabilities = IFCAP_VLAN_MTU;
ifp->if_capenable = IFCAP_VLAN_MTU;
ifp->if_start = epair_start;
ifp->if_ioctl = epair_ioctl;
ifp->if_init = epair_init;
ifp->if_snd.ifq_maxlen = ifqmaxlen;
/* We need to play some tricks here for the second interface. */
strlcpy(name, EPAIRNAME, len);
error = if_clone_create(name, len, (caddr_t)scb);
if (error)
panic("%s: if_clone_createif() for our 2nd iface failed: %d",
__func__, error);
scb->if_qflush = ifp->if_qflush;
ifp->if_qflush = epair_qflush;
ifp->if_transmit = epair_transmit;
ifp->if_baudrate = IF_Gbps(10UL); /* arbitrary maximum */
/*
* Restore name to <n>a as the ifp for this will go into the
* cloner list for the initial call.
*/
strlcpy(name, sca->ifp->if_xname, len);
DPRINTF("name='%s/%db' created sca=%p scb=%p\n", name, unit, sca, scb);
/* Initialise pseudo media types. */
ifmedia_init(&sca->media, 0, epair_media_change, epair_media_status);
ifmedia_add(&sca->media, IFM_ETHER | IFM_10G_T, 0, NULL);
ifmedia_set(&sca->media, IFM_ETHER | IFM_10G_T);
ifmedia_init(&scb->media, 0, epair_media_change, epair_media_status);
ifmedia_add(&scb->media, IFM_ETHER | IFM_10G_T, 0, NULL);
ifmedia_set(&scb->media, IFM_ETHER | IFM_10G_T);
/* Tell the world, that we are ready to rock. */
sca->ifp->if_drv_flags |= IFF_DRV_RUNNING;
scb->ifp->if_drv_flags |= IFF_DRV_RUNNING;
if_link_state_change(sca->ifp, LINK_STATE_UP);
if_link_state_change(scb->ifp, LINK_STATE_UP);
return (0);
}
static int
epair_clone_destroy(struct if_clone *ifc, struct ifnet *ifp)
{
struct ifnet *oifp;
struct epair_softc *sca, *scb;
int unit, error;
DPRINTF("ifp=%p\n", ifp);
/*
* In case we called into if_clone_destroyif() ourselves
* again to remove the second interface, the softc will be
* NULL. In that case so not do anything but return success.
*/
if (ifp->if_softc == NULL)
return (0);
unit = ifp->if_dunit;
sca = ifp->if_softc;
oifp = sca->oifp;
scb = oifp->if_softc;
DPRINTF("ifp=%p oifp=%p\n", ifp, oifp);
if_link_state_change(ifp, LINK_STATE_DOWN);
if_link_state_change(oifp, LINK_STATE_DOWN);
ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
oifp->if_drv_flags &= ~IFF_DRV_RUNNING;
ether_ifdetach(oifp);
ether_ifdetach(ifp);
/*
* Wait for all packets to be dispatched to if_input.
* The numbers can only go down as the interfaces are
* detached so there is no need to use atomics.
*/
DPRINTF("sca refcnt=%u scb refcnt=%u\n", sca->refcount, scb->refcount);
EPAIR_REFCOUNT_ASSERT(sca->refcount == 1 && scb->refcount == 1,
("%s: ifp=%p sca->refcount!=1: %d || ifp=%p scb->refcount!=1: %d",
__func__, ifp, sca->refcount, oifp, scb->refcount));
/*
* Get rid of our second half.
*/
oifp->if_softc = NULL;
error = if_clone_destroyif(ifc, oifp);
if (error)
panic("%s: if_clone_destroyif() for our 2nd iface failed: %d",
__func__, error);
/*
* Finish cleaning up. Free them and release the unit.
* As the other of the two interfaces my reside in a different vnet,
* we need to switch before freeing them.
*/
CURVNET_SET_QUIET(oifp->if_vnet);
if_free(oifp);
CURVNET_RESTORE();
if_free(ifp);
ifmedia_removeall(&sca->media);
ifmedia_removeall(&scb->media);
free(scb, M_EPAIR);
free(sca, M_EPAIR);
ifc_free_unit(ifc, unit);
return (0);
}
static int
epair_modevent(module_t mod, int type, void *data)
{
int qlimit;
switch (type) {
case MOD_LOAD:
/* For now limit us to one global mutex and one inq. */
epair_dpcpu_init();
epair_nh.nh_qlimit = 42 * ifqmaxlen; /* 42 shall be the number. */
if (TUNABLE_INT_FETCH("net.link.epair.netisr_maxqlen", &qlimit))
epair_nh.nh_qlimit = qlimit;
netisr_register(&epair_nh);
if_clone_attach(&epair_cloner);
if (bootverbose)
printf("%s initialized.\n", EPAIRNAME);
break;
case MOD_UNLOAD:
if_clone_detach(&epair_cloner);
netisr_unregister(&epair_nh);
epair_dpcpu_detach();
if (bootverbose)
printf("%s unloaded.\n", EPAIRNAME);
break;
default:
return (EOPNOTSUPP);
}
return (0);
}
static moduledata_t epair_mod = {
"if_epair",
epair_modevent,
0
};
DECLARE_MODULE(if_epair, epair_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
MODULE_VERSION(if_epair, 1);