kern/drivers/dev/ether.c - upstream - Git at Google

 #include <vfs.h>
 #include <kfs.h>
 #include <slab.h>
 #include <kmalloc.h>
 #include <kref.h>
 #include <string.h>
 #include <stdio.h>
 #include <assert.h>
 #include <error.h>
 #include <cpio.h>
 #include <pmap.h>
 #include <smp.h>
 #include <etherif.h>

 static struct ether *etherxx[Maxether];

 struct chan *etherattach(char *spec)
 {
 	ERRSTACK(2);
 	uint32_t ctlrno;
 	char *p;
 	struct chan *chan;

 	ctlrno = 0;
 	/* 'spec' is the special, i.e. l0, l1, etc. */
 	if (spec && *spec) {
 		ctlrno = strtoul(spec, &p, 0);
 		if ((ctlrno == 0 && p == spec) || *p || (ctlrno >= Maxether))
 			error(Ebadarg);
 	}
 	if (etherxx[ctlrno] == 0)
 		error(Enodev);

 	chan = devattach('l', spec);
 	if (waserror()) {
 		chanfree(chan);
 		nexterror();
 	}
 	chan->devno = ctlrno;
 	if (etherxx[ctlrno]->attach)
 		etherxx[ctlrno]->attach(etherxx[ctlrno]);

 	return chan;
 }

 static struct walkqid *etherwalk(struct chan *chan, struct chan *nchan,
 								 char **name, int nname)
 {
 	return netifwalk(&etherxx[chan->devno]->netif, chan, nchan, name, nname);
 }

 static long
 etherstat(struct chan *chan, uint8_t * dp, long n)
 {
 	return netifstat(&etherxx[chan->devno]->netif, chan, dp, n);
 }

 static struct chan *etheropen(struct chan *chan, int omode)
 {
 	return netifopen(&etherxx[chan->devno]->netif, chan, omode);
 }

 static void
 ethercreate(struct chan *u1, char *u2, int u3, int u4)
 {
 }

 static void etherclose(struct chan *chan)
 {
 	netifclose(&etherxx[chan->devno]->netif, chan);
 }

 static long
 etherread(struct chan *chan, void *buf, long n, int64_t off)
 {
 	struct ether *ether;
 	uint32_t offset = off;

 	ether = etherxx[chan->devno];
 	if ((chan->qid.type & QTDIR) == 0 && ether->ifstat) {
 		/*
 		 * With some controllers it is necessary to reach
 		 * into the chip to extract statistics.
 		 */
 		if (NETTYPE(chan->qid.path) == Nifstatqid)
 			return ether->ifstat(ether, buf, n, offset);
 		else if (NETTYPE(chan->qid.path) == Nstatqid)
 			ether->ifstat(ether, buf, 0, offset);
 	}

 	return netifread(&ether->netif, chan, buf, n, offset);
 }

 static struct block *etherbread(struct chan *chan, long n, int64_t offset)
 {
 	return netifbread(&etherxx[chan->devno]->netif, chan, n, offset);
 }

 static long
 etherwstat(struct chan *chan, uint8_t * dp, long n)
 {
 	return netifwstat(&etherxx[chan->devno]->netif, chan, dp, n);
 }

 #if 0
 part of plan 9 packet dump infrastructure.wrap output packets back to input
 	static void etherrtrace(Netfile * f, struct etherpkt *pkt, int len)
 {
 	int i, n;
 	struct block *bp;

 	if (qwindow(f->iq) <= 0)
 		return;
 	if (len > 58)
 		n = 58;
 	else
 		n = len;
 	bp = iallocb(64);
 	if (bp == NULL)
 		return;
 	memmove(bp->wp, pkt->d, n);
 	i = TK2MS(sys->ticks);
 	bp->wp[58] = len >> 8;
 	bp->wp[59] = len;
 	bp->wp[60] = i >> 24;
 	bp->wp[61] = i >> 16;
 	bp->wp[62] = i >> 8;
 	bp->wp[63] = i;
 	bp->wp += 64;
 	qpass(f->iq, bp);
 }
 #endif

 struct block *etheriq(struct ether *ether, struct block *bp, int fromwire)
 {
 	struct etherpkt *pkt;
 	uint16_t type;
 	int len, multi, tome, fromme;
 	struct netfile **ep, *f, **fp, *fx;
 	struct block *xbp;

 	ether->netif.inpackets++;

 	pkt = (struct etherpkt *)bp->rp;
 	len = BLEN(bp);
 	type = (pkt->type[0] << 8) | pkt->type[1];
 	fx = 0;
 	ep = &ether->netif.f[Ntypes];

 	multi = pkt->d[0] & 1;
 	/* check for valid multicast addresses */
 	if (multi && memcmp(pkt->d, ether->netif.bcast, sizeof(pkt->d)) != 0
 		&& ether->netif.prom == 0) {
 		if (!activemulti(&ether->netif, pkt->d, sizeof(pkt->d))) {
 			if (fromwire) {
 				freeb(bp);
 				bp = 0;
 			}
 			return bp;
 		}
 	}

 	/* is it for me? */
 	tome = memcmp(pkt->d, ether->ea, sizeof(pkt->d)) == 0;
 	fromme = memcmp(pkt->s, ether->ea, sizeof(pkt->s)) == 0;

 	/*
 	 * Multiplex the packet to all the connections which want it.
 	 * If the packet is not to be used subsequently (fromwire != 0),
 	 * attempt to simply pass it into one of the connections, thereby
 	 * saving a copy of the data (usual case hopefully).
 	 */
 	for (fp = ether->netif.f; fp < ep; fp++) {
 		if ((f = *fp))
 			if (f->type == type || f->type < 0)
 				if (tome || multi || f->prom || f->bridge & 2) {
 					/* Don't want to hear bridged packets */
 					if (f->bridge && !fromwire && !fromme)
 						continue;
 					if (!f->headersonly) {
 						if (fromwire && fx == 0)
 							fx = f;
 						else if ((xbp = iallocb(len))) {
 							memmove(xbp->wp, pkt, len);
 							xbp->wp += len;
 							if (qpass(f->iq, xbp) < 0)
 								ether->netif.soverflows++;
 						} else
 							ether->netif.soverflows++;
 					} else;	//etherrtrace(f, pkt, len);
 				}
 	}

 	if (fx) {
 		if (qpass(fx->iq, bp) < 0)
 			ether->netif.soverflows++;
 		return 0;
 	}
 	if (fromwire) {
 		freeb(bp);
 		return 0;
 	}

 	return bp;
 }

 static int
 etheroq(struct ether *ether, struct block *bp)
 {
 	int len, loopback;
 	struct etherpkt *pkt;
 	int8_t irq_state = 0;

 	ether->netif.outpackets++;

 	/*
 	 * Check if the packet has to be placed back onto the input queue,
 	 * i.e. if it's a loopback or broadcast packet or the interface is
 	 * in promiscuous mode.
 	 * If it's a loopback packet indicate to etheriq that the data isn't
 	 * needed and return, etheriq will pass-on or free the block.
 	 * To enable bridging to work, only packets that were originated
 	 * by this interface are fed back.
 	 */
 	pkt = (struct etherpkt *)bp->rp;
 	len = BLEN(bp);
 	loopback = memcmp(pkt->d, ether->ea, sizeof(pkt->d)) == 0;
 	if (loopback || memcmp(pkt->d, ether->netif.bcast, sizeof(pkt->d)) == 0
 		|| ether->netif.prom) {
 		disable_irqsave(&irq_state);
 		etheriq(ether, bp, 0);
 		enable_irqsave(&irq_state);
 	}

 	if (!loopback) {
 		qbwrite(ether->netif.oq, bp);
 		if (ether->transmit != NULL)
 			ether->transmit(ether);
 	} else
 		freeb(bp);

 	return len;
 }

 static long
 etherwrite(struct chan *chan, void *buf, long n, int64_t unused)
 {
 	ERRSTACK(2);
 	struct ether *ether;
 	struct block *bp;
 	int nn, onoff;
 	struct cmdbuf *cb;

 	ether = etherxx[chan->devno];
 	if (NETTYPE(chan->qid.path) != Ndataqid) {
 		nn = netifwrite(&ether->netif, chan, buf, n);
 		if (nn >= 0)
 			return nn;
 		cb = parsecmd(buf, n);
 		if (cb->f[0] && strcmp(cb->f[0], "nonblocking") == 0) {
 			if (cb->nf <= 1)
 				onoff = 1;
 			else
 				onoff = atoi(cb->f[1]);
 			qnoblock(ether->netif.oq, onoff);
 			kfree(cb);
 			return n;
 		}
 		kfree(cb);
 		if (ether->ctl != NULL)
 			return ether->ctl(ether, buf, n);

 		error(Ebadctl);
 	}

 	if (n > ether->netif.mtu)
 		error(Etoobig);
 	if (n < ether->netif.minmtu)
 		error(Etoosmall);

 	bp = allocb(n);
 	if (waserror()) {
 		freeb(bp);
 		nexterror();
 	}
 	memmove(bp->rp, buf, n);
 	if ((ether->netif.f[NETID(chan->qid.path)]->bridge & 2) == 0)
 		memmove(bp->rp + Eaddrlen, ether->ea, Eaddrlen);

 	bp->wp += n;

 	return etheroq(ether, bp);
 }

 static long
 etherbwrite(struct chan *chan, struct block *bp, int64_t unused)
 {
 	ERRSTACK(1);
 	struct ether *ether;
 	long n;

 	n = BLEN(bp);
 	if (NETTYPE(chan->qid.path) != Ndataqid) {
 		if (waserror()) {
 			freeb(bp);
 			nexterror();
 		}
 		n = etherwrite(chan, bp->rp, n, 0);
 		freeb(bp);
 		return n;
 	}
 	ether = etherxx[chan->devno];

 	if (n > ether->netif.mtu) {
 		freeb(bp);
 		error(Etoobig);
 	}
 	if (n < ether->netif.minmtu) {
 		freeb(bp);
 		error(Etoosmall);
 	}

 	return etheroq(ether, bp);
 }

 static struct {
 	char *type;
 	int (*reset) (struct ether *);
 } cards[Maxether + 1];

 void addethercard(char *t, int (*r) (struct ether *))
 {
 	static int ncard;

 	if (ncard == Maxether)
 		panic("too many ether cards");
 	cards[ncard].type = t;
 	cards[ncard].reset = r;
 	ncard++;
 }

 static struct ether *etherprobe(int cardno, int ctlrno)
 {
 	int i, j;
 	struct ether *ether;
 	char buf[128], name[32];

 	ether = kzmalloc(sizeof(struct ether), 0);
 	memset(ether, 0, sizeof(struct ether));
 	ether->ctlrno = ctlrno;
 	ether->netif.mbps = 10;
 	ether->netif.minmtu = ETHERMINTU;
 	ether->netif.mtu = ETHERMAXTU;
 	ether->netif.maxmtu = ETHERMAXTU;
 	qlock_init(&ether->netif.qlock);

 	if (cardno >= Maxether || cards[cardno].type == NULL) {
 		kfree(ether);
 		return NULL;
 	}
 	if (cards[cardno].reset(ether) < 0) {
 		kfree(ether);
 		return NULL;
 	}

 	/*
 	 * IRQ2 doesn't really exist, it's used to gang the interrupt
 	 * controllers together. A device set to IRQ2 will appear on
 	 * the second interrupt controller as IRQ9.
 	 */
 	if (ether->irq == 2)
 		ether->irq = 9;
 	snprintf(name, sizeof(name), "ether%d", ctlrno);

 	/*
 	 * If ether->irq is <0, it is a hack to indicate no interrupt
 	 * used by ethersink.
 	 */
 	if (ether->irq >= 0)
 		register_dev_irq(ether->irq, ether->interrupt, ether);

 	i = snprintf(buf, sizeof(buf), "#l%d: %s: %dMbps port %#p irq %d tu %d",
 				 ctlrno, cards[cardno].type, ether->netif.mbps, ether->port,
 				 ether->irq, ether->netif.mtu);
 #if 0
 	if (ether->mem)
 		i += sprint(buf + i, " addr %#p", ether->mem);

 	if (ether->size)
 		i += sprint(buf + i, " size 0x%luX", ether->size);
 #endif
 	i += snprintf(buf + i, sizeof(buf) - i,
 				  ": %2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux", ether->ea[0],
 				  ether->ea[1], ether->ea[2], ether->ea[3], ether->ea[4],
 				  ether->ea[5]);
 	snprintf(buf + i, sizeof(buf) - i, "\n");
 	printd(buf);

 	j = ether->netif.mbps;
 	if (j > 1000)
 		j *= 10;
 	for (i = 0; j >= 100; i++)
 		j /= 10;
 	i = (128 << i) * 1024;
 	netifinit(&ether->netif, name, Ntypes, i);
 	if (ether->netif.oq == 0)
 		ether->netif.oq = qopen(i, Qmsg, 0, 0);
 	if (ether->netif.oq == 0)
 		panic("etherreset %s", name);
 	ether->netif.alen = Eaddrlen;
 	memmove(ether->netif.addr, ether->ea, Eaddrlen);
 	memset(ether->netif.bcast, 0xFF, Eaddrlen);

 	return ether;
 }

 static
 void etherreset(void)
 {
 	struct ether *ether;
 	int cardno, ctlrno;

 	cardno = ctlrno = 0;
 	while (cards[cardno].type != NULL && ctlrno < Maxether) {
 		if (etherxx[ctlrno] != NULL) {
 			ctlrno++;
 			continue;
 		}
 		if ((ether = etherprobe(cardno, ctlrno)) == NULL) {
 			cardno++;
 			continue;
 		}
 		etherxx[ctlrno] = ether;
 		ctlrno++;
 	}
 }

 static void ethershutdown(void)
 {
 	char name[32];
 	int i;
 	struct ether *ether;

 	for (i = 0; i < Maxether; i++) {
 		ether = etherxx[i];
 		if (ether == NULL)
 			continue;
 		if (ether->shutdown == NULL) {
 			printd("#l%d: no shutdown function\n", i);
 			continue;
 		}
 		snprintf(name, sizeof(name), "ether%d", i);
 		if (ether->irq >= 0) {
 			//  intrdisable(ether->irq, ether->interrupt, ether, ether->tbdf, name);
 		}
 		(*ether->shutdown) (ether);
 	}
 }

 #define ROLYPOLY 0xedb88320

 /* really slow 32 bit crc for ethers */
 uint32_t ethercrc(uint8_t * p, int len)
 {
 	int i, j;
 	uint32_t crc, b;

 	crc = 0xffffffff;
 	for (i = 0; i < len; i++) {
 		b = *p++;
 		for (j = 0; j < 8; j++) {
 			crc = (crc >> 1) ^ (((crc ^ b) & 1) ? ROLYPOLY : 0);
 			b >>= 1;
 		}
 	}
 	return crc;
 }

 struct dev etherdevtab = {
 	'l',
 	"ether",

 	etherreset,
 	devinit,
 	ethershutdown,
 	etherattach,
 	etherwalk,
 	etherstat,
 	etheropen,
 	ethercreate,
 	etherclose,
 	etherread,
 	etherbread,
 	etherwrite,
 	etherbwrite,
 	devremove,
 	etherwstat,
 	devpower,
 	devconfig,
 	devchaninfo,
 };
	#include <vfs.h>
	#include <kfs.h>
	#include <slab.h>
	#include <kmalloc.h>
	#include <kref.h>
	#include <string.h>
	#include <stdio.h>
	#include <assert.h>
	#include <error.h>
	#include <cpio.h>
	#include <pmap.h>
	#include <smp.h>
	#include <etherif.h>

	static struct ether *etherxx[Maxether];

	struct chan etherattach(char spec)
	{
	ERRSTACK(2);
	uint32_t ctlrno;
	char *p;
	struct chan *chan;

	ctlrno = 0;
	/* 'spec' is the special, i.e. l0, l1, etc. */
	if (spec && *spec) {
	ctlrno = strtoul(spec, &p, 0);
	if ((ctlrno == 0 && p == spec) \|\| *p \|\| (ctlrno >= Maxether))
	error(Ebadarg);
	}
	if (etherxx[ctlrno] == 0)
	error(Enodev);

	chan = devattach('l', spec);
	if (waserror()) {
	chanfree(chan);
	nexterror();
	}
	chan->devno = ctlrno;
	if (etherxx[ctlrno]->attach)
	etherxx[ctlrno]->attach(etherxx[ctlrno]);

	return chan;
	}

	static struct walkqid etherwalk(struct chan chan, struct chan *nchan,
	char **name, int nname)
	{
	return netifwalk(&etherxx[chan->devno]->netif, chan, nchan, name, nname);
	}

	static long
	etherstat(struct chan chan, uint8_t dp, long n)
	{
	return netifstat(&etherxx[chan->devno]->netif, chan, dp, n);
	}

	static struct chan etheropen(struct chan chan, int omode)
	{
	return netifopen(&etherxx[chan->devno]->netif, chan, omode);
	}

	static void
	ethercreate(struct chan u1, char u2, int u3, int u4)
	{
	}

	static void etherclose(struct chan *chan)
	{
	netifclose(&etherxx[chan->devno]->netif, chan);
	}

	static long
	etherread(struct chan chan, void buf, long n, int64_t off)
	{
	struct ether *ether;
	uint32_t offset = off;

	ether = etherxx[chan->devno];
	if ((chan->qid.type & QTDIR) == 0 && ether->ifstat) {
	/*
	* With some controllers it is necessary to reach
	* into the chip to extract statistics.
	*/
	if (NETTYPE(chan->qid.path) == Nifstatqid)
	return ether->ifstat(ether, buf, n, offset);
	else if (NETTYPE(chan->qid.path) == Nstatqid)
	ether->ifstat(ether, buf, 0, offset);
	}

	return netifread(&ether->netif, chan, buf, n, offset);
	}

	static struct block etherbread(struct chan chan, long n, int64_t offset)
	{
	return netifbread(&etherxx[chan->devno]->netif, chan, n, offset);
	}

	static long
	etherwstat(struct chan chan, uint8_t dp, long n)
	{
	return netifwstat(&etherxx[chan->devno]->netif, chan, dp, n);
	}

	#if 0
	part of plan 9 packet dump infrastructure.wrap output packets back to input
	static void etherrtrace(Netfile * f, struct etherpkt *pkt, int len)
	{
	int i, n;
	struct block *bp;

	if (qwindow(f->iq) <= 0)
	return;
	if (len > 58)
	n = 58;
	else
	n = len;
	bp = iallocb(64);
	if (bp == NULL)
	return;
	memmove(bp->wp, pkt->d, n);
	i = TK2MS(sys->ticks);
	bp->wp[58] = len >> 8;
	bp->wp[59] = len;
	bp->wp[60] = i >> 24;
	bp->wp[61] = i >> 16;
	bp->wp[62] = i >> 8;
	bp->wp[63] = i;
	bp->wp += 64;
	qpass(f->iq, bp);
	}
	#endif

	struct block etheriq(struct ether ether, struct block *bp, int fromwire)
	{
	struct etherpkt *pkt;
	uint16_t type;
	int len, multi, tome, fromme;
	struct netfile *ep, f, *fp, fx;
	struct block *xbp;

	ether->netif.inpackets++;

	pkt = (struct etherpkt *)bp->rp;
	len = BLEN(bp);
	type = (pkt->type[0] << 8) \| pkt->type[1];
	fx = 0;
	ep = &ether->netif.f[Ntypes];

	multi = pkt->d[0] & 1;
	/* check for valid multicast addresses */
	if (multi && memcmp(pkt->d, ether->netif.bcast, sizeof(pkt->d)) != 0
	&& ether->netif.prom == 0) {
	if (!activemulti(&ether->netif, pkt->d, sizeof(pkt->d))) {
	if (fromwire) {
	freeb(bp);
	bp = 0;
	}
	return bp;
	}
	}

	/* is it for me? */
	tome = memcmp(pkt->d, ether->ea, sizeof(pkt->d)) == 0;
	fromme = memcmp(pkt->s, ether->ea, sizeof(pkt->s)) == 0;

	/*
	* Multiplex the packet to all the connections which want it.
	* If the packet is not to be used subsequently (fromwire != 0),
	* attempt to simply pass it into one of the connections, thereby
	* saving a copy of the data (usual case hopefully).
	*/
	for (fp = ether->netif.f; fp < ep; fp++) {
	if ((f = *fp))
	if (f->type == type \|\| f->type < 0)
	if (tome \|\| multi \|\| f->prom \|\| f->bridge & 2) {
	/* Don't want to hear bridged packets */
	if (f->bridge && !fromwire && !fromme)
	continue;
	if (!f->headersonly) {
	if (fromwire && fx == 0)
	fx = f;
	else if ((xbp = iallocb(len))) {
	memmove(xbp->wp, pkt, len);
	xbp->wp += len;
	if (qpass(f->iq, xbp) < 0)
	ether->netif.soverflows++;
	} else
	ether->netif.soverflows++;
	} else; //etherrtrace(f, pkt, len);
	}
	}

	if (fx) {
	if (qpass(fx->iq, bp) < 0)
	ether->netif.soverflows++;
	return 0;
	}
	if (fromwire) {
	freeb(bp);
	return 0;
	}

	return bp;
	}

	static int
	etheroq(struct ether ether, struct block bp)
	{
	int len, loopback;
	struct etherpkt *pkt;
	int8_t irq_state = 0;

	ether->netif.outpackets++;

	/*
	* Check if the packet has to be placed back onto the input queue,
	* i.e. if it's a loopback or broadcast packet or the interface is
	* in promiscuous mode.
	* If it's a loopback packet indicate to etheriq that the data isn't
	* needed and return, etheriq will pass-on or free the block.
	* To enable bridging to work, only packets that were originated
	* by this interface are fed back.
	*/
	pkt = (struct etherpkt *)bp->rp;
	len = BLEN(bp);
	loopback = memcmp(pkt->d, ether->ea, sizeof(pkt->d)) == 0;
	if (loopback \|\| memcmp(pkt->d, ether->netif.bcast, sizeof(pkt->d)) == 0
	\|\| ether->netif.prom) {
	disable_irqsave(&irq_state);
	etheriq(ether, bp, 0);
	enable_irqsave(&irq_state);
	}

	if (!loopback) {
	qbwrite(ether->netif.oq, bp);
	if (ether->transmit != NULL)
	ether->transmit(ether);
	} else
	freeb(bp);

	return len;
	}

	static long
	etherwrite(struct chan chan, void buf, long n, int64_t unused)
	{
	ERRSTACK(2);
	struct ether *ether;
	struct block *bp;
	int nn, onoff;
	struct cmdbuf *cb;

	ether = etherxx[chan->devno];
	if (NETTYPE(chan->qid.path) != Ndataqid) {
	nn = netifwrite(&ether->netif, chan, buf, n);
	if (nn >= 0)
	return nn;
	cb = parsecmd(buf, n);
	if (cb->f[0] && strcmp(cb->f[0], "nonblocking") == 0) {
	if (cb->nf <= 1)
	onoff = 1;
	else
	onoff = atoi(cb->f[1]);
	qnoblock(ether->netif.oq, onoff);
	kfree(cb);
	return n;
	}
	kfree(cb);
	if (ether->ctl != NULL)
	return ether->ctl(ether, buf, n);

	error(Ebadctl);
	}

	if (n > ether->netif.mtu)
	error(Etoobig);
	if (n < ether->netif.minmtu)
	error(Etoosmall);

	bp = allocb(n);
	if (waserror()) {
	freeb(bp);
	nexterror();
	}
	memmove(bp->rp, buf, n);
	if ((ether->netif.f[NETID(chan->qid.path)]->bridge & 2) == 0)
	memmove(bp->rp + Eaddrlen, ether->ea, Eaddrlen);

	bp->wp += n;

	return etheroq(ether, bp);
	}

	static long
	etherbwrite(struct chan chan, struct block bp, int64_t unused)
	{
	ERRSTACK(1);
	struct ether *ether;
	long n;

	n = BLEN(bp);
	if (NETTYPE(chan->qid.path) != Ndataqid) {
	if (waserror()) {
	freeb(bp);
	nexterror();
	}
	n = etherwrite(chan, bp->rp, n, 0);
	freeb(bp);
	return n;
	}
	ether = etherxx[chan->devno];

	if (n > ether->netif.mtu) {
	freeb(bp);
	error(Etoobig);
	}
	if (n < ether->netif.minmtu) {
	freeb(bp);
	error(Etoosmall);
	}

	return etheroq(ether, bp);
	}

	static struct {
	char *type;
	int (reset) (struct ether );
	} cards[Maxether + 1];

	void addethercard(char t, int (r) (struct ether *))
	{
	static int ncard;

	if (ncard == Maxether)
	panic("too many ether cards");
	cards[ncard].type = t;
	cards[ncard].reset = r;
	ncard++;
	}

	static struct ether *etherprobe(int cardno, int ctlrno)
	{
	int i, j;
	struct ether *ether;
	char buf[128], name[32];

	ether = kzmalloc(sizeof(struct ether), 0);
	memset(ether, 0, sizeof(struct ether));
	ether->ctlrno = ctlrno;
	ether->netif.mbps = 10;
	ether->netif.minmtu = ETHERMINTU;
	ether->netif.mtu = ETHERMAXTU;
	ether->netif.maxmtu = ETHERMAXTU;
	qlock_init(&ether->netif.qlock);

	if (cardno >= Maxether \|\| cards[cardno].type == NULL) {
	kfree(ether);
	return NULL;
	}
	if (cards[cardno].reset(ether) < 0) {
	kfree(ether);
	return NULL;
	}

	/*
	* IRQ2 doesn't really exist, it's used to gang the interrupt
	* controllers together. A device set to IRQ2 will appear on
	* the second interrupt controller as IRQ9.
	*/
	if (ether->irq == 2)
	ether->irq = 9;
	snprintf(name, sizeof(name), "ether%d", ctlrno);

	/*
	* If ether->irq is <0, it is a hack to indicate no interrupt
	* used by ethersink.
	*/
	if (ether->irq >= 0)
	register_dev_irq(ether->irq, ether->interrupt, ether);

	i = snprintf(buf, sizeof(buf), "#l%d: %s: %dMbps port %#p irq %d tu %d",
	ctlrno, cards[cardno].type, ether->netif.mbps, ether->port,
	ether->irq, ether->netif.mtu);
	#if 0
	if (ether->mem)
	i += sprint(buf + i, " addr %#p", ether->mem);

	if (ether->size)
	i += sprint(buf + i, " size 0x%luX", ether->size);
	#endif
	i += snprintf(buf + i, sizeof(buf) - i,
	": %2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux", ether->ea[0],
	ether->ea[1], ether->ea[2], ether->ea[3], ether->ea[4],
	ether->ea[5]);
	snprintf(buf + i, sizeof(buf) - i, "\n");
	printd(buf);

	j = ether->netif.mbps;
	if (j > 1000)
	j *= 10;
	for (i = 0; j >= 100; i++)
	j /= 10;
	i = (128 << i) * 1024;
	netifinit(&ether->netif, name, Ntypes, i);
	if (ether->netif.oq == 0)
	ether->netif.oq = qopen(i, Qmsg, 0, 0);
	if (ether->netif.oq == 0)
	panic("etherreset %s", name);
	ether->netif.alen = Eaddrlen;
	memmove(ether->netif.addr, ether->ea, Eaddrlen);
	memset(ether->netif.bcast, 0xFF, Eaddrlen);

	return ether;
	}

	static
	void etherreset(void)
	{
	struct ether *ether;
	int cardno, ctlrno;

	cardno = ctlrno = 0;
	while (cards[cardno].type != NULL && ctlrno < Maxether) {
	if (etherxx[ctlrno] != NULL) {
	ctlrno++;
	continue;
	}
	if ((ether = etherprobe(cardno, ctlrno)) == NULL) {
	cardno++;
	continue;
	}
	etherxx[ctlrno] = ether;
	ctlrno++;
	}
	}

	static void ethershutdown(void)
	{
	char name[32];
	int i;
	struct ether *ether;

	for (i = 0; i < Maxether; i++) {
	ether = etherxx[i];
	if (ether == NULL)
	continue;
	if (ether->shutdown == NULL) {
	printd("#l%d: no shutdown function\n", i);
	continue;
	}
	snprintf(name, sizeof(name), "ether%d", i);
	if (ether->irq >= 0) {
	// intrdisable(ether->irq, ether->interrupt, ether, ether->tbdf, name);
	}
	(*ether->shutdown) (ether);
	}
	}

	#define ROLYPOLY 0xedb88320

	/* really slow 32 bit crc for ethers */
	uint32_t ethercrc(uint8_t * p, int len)
	{
	int i, j;
	uint32_t crc, b;

	crc = 0xffffffff;
	for (i = 0; i < len; i++) {
	b = *p++;
	for (j = 0; j < 8; j++) {
	crc = (crc >> 1) ^ (((crc ^ b) & 1) ? ROLYPOLY : 0);
	b >>= 1;
	}
	}
	return crc;
	}

	struct dev etherdevtab = {
	'l',
	"ether",

	etherreset,
	devinit,
	ethershutdown,
	etherattach,
	etherwalk,
	etherstat,
	etheropen,
	ethercreate,
	etherclose,
	etherread,
	etherbread,
	etherwrite,
	etherbwrite,
	devremove,
	etherwstat,
	devpower,
	devconfig,
	devchaninfo,
	};