1 /*
2  * This file is part of the Chelsio T4 Ethernet driver for Linux.
3  *
4  * Copyright (c) 2003-2014 Chelsio Communications, Inc. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  */
34 
35 #include <linux/skbuff.h>
36 #include <linux/netdevice.h>
37 #include <linux/if.h>
38 #include <linux/if_vlan.h>
39 #include <linux/jhash.h>
40 #include <linux/module.h>
41 #include <linux/debugfs.h>
42 #include <linux/seq_file.h>
43 #include <net/neighbour.h>
44 #include "cxgb4.h"
45 #include "l2t.h"
46 #include "t4_msg.h"
47 #include "t4fw_api.h"
48 #include "t4_regs.h"
49 #include "t4_values.h"
50 
51 #define VLAN_NONE 0xfff
52 
53 /* identifies sync vs async L2T_WRITE_REQs */
54 #define F_SYNC_WR    (1 << 12)
55 
56 enum {
57 	L2T_STATE_VALID,      /* entry is up to date */
58 	L2T_STATE_STALE,      /* entry may be used but needs revalidation */
59 	L2T_STATE_RESOLVING,  /* entry needs address resolution */
60 	L2T_STATE_SYNC_WRITE, /* synchronous write of entry underway */
61 
62 	/* when state is one of the below the entry is not hashed */
63 	L2T_STATE_SWITCHING,  /* entry is being used by a switching filter */
64 	L2T_STATE_UNUSED      /* entry not in use */
65 };
66 
67 struct l2t_data {
68 	rwlock_t lock;
69 	atomic_t nfree;             /* number of free entries */
70 	struct l2t_entry *rover;    /* starting point for next allocation */
71 	struct l2t_entry l2tab[L2T_SIZE];
72 };
73 
74 static inline unsigned int vlan_prio(const struct l2t_entry *e)
75 {
76 	return e->vlan >> 13;
77 }
78 
79 static inline void l2t_hold(struct l2t_data *d, struct l2t_entry *e)
80 {
81 	if (atomic_add_return(1, &e->refcnt) == 1)  /* 0 -> 1 transition */
82 		atomic_dec(&d->nfree);
83 }
84 
85 /*
86  * To avoid having to check address families we do not allow v4 and v6
87  * neighbors to be on the same hash chain.  We keep v4 entries in the first
88  * half of available hash buckets and v6 in the second.
89  */
90 enum {
91 	L2T_SZ_HALF = L2T_SIZE / 2,
92 	L2T_HASH_MASK = L2T_SZ_HALF - 1
93 };
94 
95 static inline unsigned int arp_hash(const u32 *key, int ifindex)
96 {
97 	return jhash_2words(*key, ifindex, 0) & L2T_HASH_MASK;
98 }
99 
100 static inline unsigned int ipv6_hash(const u32 *key, int ifindex)
101 {
102 	u32 xor = key[0] ^ key[1] ^ key[2] ^ key[3];
103 
104 	return L2T_SZ_HALF + (jhash_2words(xor, ifindex, 0) & L2T_HASH_MASK);
105 }
106 
107 static unsigned int addr_hash(const u32 *addr, int addr_len, int ifindex)
108 {
109 	return addr_len == 4 ? arp_hash(addr, ifindex) :
110 			       ipv6_hash(addr, ifindex);
111 }
112 
113 /*
114  * Checks if an L2T entry is for the given IP/IPv6 address.  It does not check
115  * whether the L2T entry and the address are of the same address family.
116  * Callers ensure an address is only checked against L2T entries of the same
117  * family, something made trivial by the separation of IP and IPv6 hash chains
118  * mentioned above.  Returns 0 if there's a match,
119  */
120 static int addreq(const struct l2t_entry *e, const u32 *addr)
121 {
122 	if (e->v6)
123 		return (e->addr[0] ^ addr[0]) | (e->addr[1] ^ addr[1]) |
124 		       (e->addr[2] ^ addr[2]) | (e->addr[3] ^ addr[3]);
125 	return e->addr[0] ^ addr[0];
126 }
127 
128 static void neigh_replace(struct l2t_entry *e, struct neighbour *n)
129 {
130 	neigh_hold(n);
131 	if (e->neigh)
132 		neigh_release(e->neigh);
133 	e->neigh = n;
134 }
135 
136 /*
137  * Write an L2T entry.  Must be called with the entry locked.
138  * The write may be synchronous or asynchronous.
139  */
140 static int write_l2e(struct adapter *adap, struct l2t_entry *e, int sync)
141 {
142 	struct sk_buff *skb;
143 	struct cpl_l2t_write_req *req;
144 
145 	skb = alloc_skb(sizeof(*req), GFP_ATOMIC);
146 	if (!skb)
147 		return -ENOMEM;
148 
149 	req = (struct cpl_l2t_write_req *)__skb_put(skb, sizeof(*req));
150 	INIT_TP_WR(req, 0);
151 
152 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ,
153 					e->idx | (sync ? F_SYNC_WR : 0) |
154 					TID_QID_V(adap->sge.fw_evtq.abs_id)));
155 	req->params = htons(L2T_W_PORT_V(e->lport) | L2T_W_NOREPLY_V(!sync));
156 	req->l2t_idx = htons(e->idx);
157 	req->vlan = htons(e->vlan);
158 	if (e->neigh && !(e->neigh->dev->flags & IFF_LOOPBACK))
159 		memcpy(e->dmac, e->neigh->ha, sizeof(e->dmac));
160 	memcpy(req->dst_mac, e->dmac, sizeof(req->dst_mac));
161 
162 	set_wr_txq(skb, CPL_PRIORITY_CONTROL, 0);
163 	t4_ofld_send(adap, skb);
164 
165 	if (sync && e->state != L2T_STATE_SWITCHING)
166 		e->state = L2T_STATE_SYNC_WRITE;
167 	return 0;
168 }
169 
170 /*
171  * Send packets waiting in an L2T entry's ARP queue.  Must be called with the
172  * entry locked.
173  */
174 static void send_pending(struct adapter *adap, struct l2t_entry *e)
175 {
176 	while (e->arpq_head) {
177 		struct sk_buff *skb = e->arpq_head;
178 
179 		e->arpq_head = skb->next;
180 		skb->next = NULL;
181 		t4_ofld_send(adap, skb);
182 	}
183 	e->arpq_tail = NULL;
184 }
185 
186 /*
187  * Process a CPL_L2T_WRITE_RPL.  Wake up the ARP queue if it completes a
188  * synchronous L2T_WRITE.  Note that the TID in the reply is really the L2T
189  * index it refers to.
190  */
191 void do_l2t_write_rpl(struct adapter *adap, const struct cpl_l2t_write_rpl *rpl)
192 {
193 	unsigned int tid = GET_TID(rpl);
194 	unsigned int idx = tid & (L2T_SIZE - 1);
195 
196 	if (unlikely(rpl->status != CPL_ERR_NONE)) {
197 		dev_err(adap->pdev_dev,
198 			"Unexpected L2T_WRITE_RPL status %u for entry %u\n",
199 			rpl->status, idx);
200 		return;
201 	}
202 
203 	if (tid & F_SYNC_WR) {
204 		struct l2t_entry *e = &adap->l2t->l2tab[idx];
205 
206 		spin_lock(&e->lock);
207 		if (e->state != L2T_STATE_SWITCHING) {
208 			send_pending(adap, e);
209 			e->state = (e->neigh->nud_state & NUD_STALE) ?
210 					L2T_STATE_STALE : L2T_STATE_VALID;
211 		}
212 		spin_unlock(&e->lock);
213 	}
214 }
215 
216 /*
217  * Add a packet to an L2T entry's queue of packets awaiting resolution.
218  * Must be called with the entry's lock held.
219  */
220 static inline void arpq_enqueue(struct l2t_entry *e, struct sk_buff *skb)
221 {
222 	skb->next = NULL;
223 	if (e->arpq_head)
224 		e->arpq_tail->next = skb;
225 	else
226 		e->arpq_head = skb;
227 	e->arpq_tail = skb;
228 }
229 
230 int cxgb4_l2t_send(struct net_device *dev, struct sk_buff *skb,
231 		   struct l2t_entry *e)
232 {
233 	struct adapter *adap = netdev2adap(dev);
234 
235 again:
236 	switch (e->state) {
237 	case L2T_STATE_STALE:     /* entry is stale, kick off revalidation */
238 		neigh_event_send(e->neigh, NULL);
239 		spin_lock_bh(&e->lock);
240 		if (e->state == L2T_STATE_STALE)
241 			e->state = L2T_STATE_VALID;
242 		spin_unlock_bh(&e->lock);
243 	case L2T_STATE_VALID:     /* fast-path, send the packet on */
244 		return t4_ofld_send(adap, skb);
245 	case L2T_STATE_RESOLVING:
246 	case L2T_STATE_SYNC_WRITE:
247 		spin_lock_bh(&e->lock);
248 		if (e->state != L2T_STATE_SYNC_WRITE &&
249 		    e->state != L2T_STATE_RESOLVING) {
250 			spin_unlock_bh(&e->lock);
251 			goto again;
252 		}
253 		arpq_enqueue(e, skb);
254 		spin_unlock_bh(&e->lock);
255 
256 		if (e->state == L2T_STATE_RESOLVING &&
257 		    !neigh_event_send(e->neigh, NULL)) {
258 			spin_lock_bh(&e->lock);
259 			if (e->state == L2T_STATE_RESOLVING && e->arpq_head)
260 				write_l2e(adap, e, 1);
261 			spin_unlock_bh(&e->lock);
262 		}
263 	}
264 	return 0;
265 }
266 EXPORT_SYMBOL(cxgb4_l2t_send);
267 
268 /*
269  * Allocate a free L2T entry.  Must be called with l2t_data.lock held.
270  */
271 static struct l2t_entry *alloc_l2e(struct l2t_data *d)
272 {
273 	struct l2t_entry *end, *e, **p;
274 
275 	if (!atomic_read(&d->nfree))
276 		return NULL;
277 
278 	/* there's definitely a free entry */
279 	for (e = d->rover, end = &d->l2tab[L2T_SIZE]; e != end; ++e)
280 		if (atomic_read(&e->refcnt) == 0)
281 			goto found;
282 
283 	for (e = d->l2tab; atomic_read(&e->refcnt); ++e)
284 		;
285 found:
286 	d->rover = e + 1;
287 	atomic_dec(&d->nfree);
288 
289 	/*
290 	 * The entry we found may be an inactive entry that is
291 	 * presently in the hash table.  We need to remove it.
292 	 */
293 	if (e->state < L2T_STATE_SWITCHING)
294 		for (p = &d->l2tab[e->hash].first; *p; p = &(*p)->next)
295 			if (*p == e) {
296 				*p = e->next;
297 				e->next = NULL;
298 				break;
299 			}
300 
301 	e->state = L2T_STATE_UNUSED;
302 	return e;
303 }
304 
305 /*
306  * Called when an L2T entry has no more users.
307  */
308 static void t4_l2e_free(struct l2t_entry *e)
309 {
310 	struct l2t_data *d;
311 
312 	spin_lock_bh(&e->lock);
313 	if (atomic_read(&e->refcnt) == 0) {  /* hasn't been recycled */
314 		if (e->neigh) {
315 			neigh_release(e->neigh);
316 			e->neigh = NULL;
317 		}
318 		while (e->arpq_head) {
319 			struct sk_buff *skb = e->arpq_head;
320 
321 			e->arpq_head = skb->next;
322 			kfree_skb(skb);
323 		}
324 		e->arpq_tail = NULL;
325 	}
326 	spin_unlock_bh(&e->lock);
327 
328 	d = container_of(e, struct l2t_data, l2tab[e->idx]);
329 	atomic_inc(&d->nfree);
330 }
331 
332 void cxgb4_l2t_release(struct l2t_entry *e)
333 {
334 	if (atomic_dec_and_test(&e->refcnt))
335 		t4_l2e_free(e);
336 }
337 EXPORT_SYMBOL(cxgb4_l2t_release);
338 
339 /*
340  * Update an L2T entry that was previously used for the same next hop as neigh.
341  * Must be called with softirqs disabled.
342  */
343 static void reuse_entry(struct l2t_entry *e, struct neighbour *neigh)
344 {
345 	unsigned int nud_state;
346 
347 	spin_lock(&e->lock);                /* avoid race with t4_l2t_free */
348 	if (neigh != e->neigh)
349 		neigh_replace(e, neigh);
350 	nud_state = neigh->nud_state;
351 	if (memcmp(e->dmac, neigh->ha, sizeof(e->dmac)) ||
352 	    !(nud_state & NUD_VALID))
353 		e->state = L2T_STATE_RESOLVING;
354 	else if (nud_state & NUD_CONNECTED)
355 		e->state = L2T_STATE_VALID;
356 	else
357 		e->state = L2T_STATE_STALE;
358 	spin_unlock(&e->lock);
359 }
360 
361 struct l2t_entry *cxgb4_l2t_get(struct l2t_data *d, struct neighbour *neigh,
362 				const struct net_device *physdev,
363 				unsigned int priority)
364 {
365 	u8 lport;
366 	u16 vlan;
367 	struct l2t_entry *e;
368 	int addr_len = neigh->tbl->key_len;
369 	u32 *addr = (u32 *)neigh->primary_key;
370 	int ifidx = neigh->dev->ifindex;
371 	int hash = addr_hash(addr, addr_len, ifidx);
372 
373 	if (neigh->dev->flags & IFF_LOOPBACK)
374 		lport = netdev2pinfo(physdev)->tx_chan + 4;
375 	else
376 		lport = netdev2pinfo(physdev)->lport;
377 
378 	if (neigh->dev->priv_flags & IFF_802_1Q_VLAN)
379 		vlan = vlan_dev_vlan_id(neigh->dev);
380 	else
381 		vlan = VLAN_NONE;
382 
383 	write_lock_bh(&d->lock);
384 	for (e = d->l2tab[hash].first; e; e = e->next)
385 		if (!addreq(e, addr) && e->ifindex == ifidx &&
386 		    e->vlan == vlan && e->lport == lport) {
387 			l2t_hold(d, e);
388 			if (atomic_read(&e->refcnt) == 1)
389 				reuse_entry(e, neigh);
390 			goto done;
391 		}
392 
393 	/* Need to allocate a new entry */
394 	e = alloc_l2e(d);
395 	if (e) {
396 		spin_lock(&e->lock);          /* avoid race with t4_l2t_free */
397 		e->state = L2T_STATE_RESOLVING;
398 		if (neigh->dev->flags & IFF_LOOPBACK)
399 			memcpy(e->dmac, physdev->dev_addr, sizeof(e->dmac));
400 		memcpy(e->addr, addr, addr_len);
401 		e->ifindex = ifidx;
402 		e->hash = hash;
403 		e->lport = lport;
404 		e->v6 = addr_len == 16;
405 		atomic_set(&e->refcnt, 1);
406 		neigh_replace(e, neigh);
407 		e->vlan = vlan;
408 		e->next = d->l2tab[hash].first;
409 		d->l2tab[hash].first = e;
410 		spin_unlock(&e->lock);
411 	}
412 done:
413 	write_unlock_bh(&d->lock);
414 	return e;
415 }
416 EXPORT_SYMBOL(cxgb4_l2t_get);
417 
418 u64 cxgb4_select_ntuple(struct net_device *dev,
419 			const struct l2t_entry *l2t)
420 {
421 	struct adapter *adap = netdev2adap(dev);
422 	struct tp_params *tp = &adap->params.tp;
423 	u64 ntuple = 0;
424 
425 	/* Initialize each of the fields which we care about which are present
426 	 * in the Compressed Filter Tuple.
427 	 */
428 	if (tp->vlan_shift >= 0 && l2t->vlan != VLAN_NONE)
429 		ntuple |= (u64)(FT_VLAN_VLD_F | l2t->vlan) << tp->vlan_shift;
430 
431 	if (tp->port_shift >= 0)
432 		ntuple |= (u64)l2t->lport << tp->port_shift;
433 
434 	if (tp->protocol_shift >= 0)
435 		ntuple |= (u64)IPPROTO_TCP << tp->protocol_shift;
436 
437 	if (tp->vnic_shift >= 0) {
438 		u32 viid = cxgb4_port_viid(dev);
439 		u32 vf = FW_VIID_VIN_G(viid);
440 		u32 pf = FW_VIID_PFN_G(viid);
441 		u32 vld = FW_VIID_VIVLD_G(viid);
442 
443 		ntuple |= (u64)(FT_VNID_ID_VF_V(vf) |
444 				FT_VNID_ID_PF_V(pf) |
445 				FT_VNID_ID_VLD_V(vld)) << tp->vnic_shift;
446 	}
447 
448 	return ntuple;
449 }
450 EXPORT_SYMBOL(cxgb4_select_ntuple);
451 
452 /*
453  * Called when address resolution fails for an L2T entry to handle packets
454  * on the arpq head.  If a packet specifies a failure handler it is invoked,
455  * otherwise the packet is sent to the device.
456  */
457 static void handle_failed_resolution(struct adapter *adap, struct sk_buff *arpq)
458 {
459 	while (arpq) {
460 		struct sk_buff *skb = arpq;
461 		const struct l2t_skb_cb *cb = L2T_SKB_CB(skb);
462 
463 		arpq = skb->next;
464 		skb->next = NULL;
465 		if (cb->arp_err_handler)
466 			cb->arp_err_handler(cb->handle, skb);
467 		else
468 			t4_ofld_send(adap, skb);
469 	}
470 }
471 
472 /*
473  * Called when the host's neighbor layer makes a change to some entry that is
474  * loaded into the HW L2 table.
475  */
476 void t4_l2t_update(struct adapter *adap, struct neighbour *neigh)
477 {
478 	struct l2t_entry *e;
479 	struct sk_buff *arpq = NULL;
480 	struct l2t_data *d = adap->l2t;
481 	int addr_len = neigh->tbl->key_len;
482 	u32 *addr = (u32 *) neigh->primary_key;
483 	int ifidx = neigh->dev->ifindex;
484 	int hash = addr_hash(addr, addr_len, ifidx);
485 
486 	read_lock_bh(&d->lock);
487 	for (e = d->l2tab[hash].first; e; e = e->next)
488 		if (!addreq(e, addr) && e->ifindex == ifidx) {
489 			spin_lock(&e->lock);
490 			if (atomic_read(&e->refcnt))
491 				goto found;
492 			spin_unlock(&e->lock);
493 			break;
494 		}
495 	read_unlock_bh(&d->lock);
496 	return;
497 
498  found:
499 	read_unlock(&d->lock);
500 
501 	if (neigh != e->neigh)
502 		neigh_replace(e, neigh);
503 
504 	if (e->state == L2T_STATE_RESOLVING) {
505 		if (neigh->nud_state & NUD_FAILED) {
506 			arpq = e->arpq_head;
507 			e->arpq_head = e->arpq_tail = NULL;
508 		} else if ((neigh->nud_state & (NUD_CONNECTED | NUD_STALE)) &&
509 			   e->arpq_head) {
510 			write_l2e(adap, e, 1);
511 		}
512 	} else {
513 		e->state = neigh->nud_state & NUD_CONNECTED ?
514 			L2T_STATE_VALID : L2T_STATE_STALE;
515 		if (memcmp(e->dmac, neigh->ha, sizeof(e->dmac)))
516 			write_l2e(adap, e, 0);
517 	}
518 
519 	spin_unlock_bh(&e->lock);
520 
521 	if (arpq)
522 		handle_failed_resolution(adap, arpq);
523 }
524 
525 /* Allocate an L2T entry for use by a switching rule.  Such need to be
526  * explicitly freed and while busy they are not on any hash chain, so normal
527  * address resolution updates do not see them.
528  */
529 struct l2t_entry *t4_l2t_alloc_switching(struct l2t_data *d)
530 {
531 	struct l2t_entry *e;
532 
533 	write_lock_bh(&d->lock);
534 	e = alloc_l2e(d);
535 	if (e) {
536 		spin_lock(&e->lock);          /* avoid race with t4_l2t_free */
537 		e->state = L2T_STATE_SWITCHING;
538 		atomic_set(&e->refcnt, 1);
539 		spin_unlock(&e->lock);
540 	}
541 	write_unlock_bh(&d->lock);
542 	return e;
543 }
544 
545 /* Sets/updates the contents of a switching L2T entry that has been allocated
546  * with an earlier call to @t4_l2t_alloc_switching.
547  */
548 int t4_l2t_set_switching(struct adapter *adap, struct l2t_entry *e, u16 vlan,
549 		u8 port, u8 *eth_addr)
550 {
551 	e->vlan = vlan;
552 	e->lport = port;
553 	memcpy(e->dmac, eth_addr, ETH_ALEN);
554 	return write_l2e(adap, e, 0);
555 }
556 
557 struct l2t_data *t4_init_l2t(void)
558 {
559 	int i;
560 	struct l2t_data *d;
561 
562 	d = t4_alloc_mem(sizeof(*d));
563 	if (!d)
564 		return NULL;
565 
566 	d->rover = d->l2tab;
567 	atomic_set(&d->nfree, L2T_SIZE);
568 	rwlock_init(&d->lock);
569 
570 	for (i = 0; i < L2T_SIZE; ++i) {
571 		d->l2tab[i].idx = i;
572 		d->l2tab[i].state = L2T_STATE_UNUSED;
573 		spin_lock_init(&d->l2tab[i].lock);
574 		atomic_set(&d->l2tab[i].refcnt, 0);
575 	}
576 	return d;
577 }
578 
579 static inline void *l2t_get_idx(struct seq_file *seq, loff_t pos)
580 {
581 	struct l2t_entry *l2tab = seq->private;
582 
583 	return pos >= L2T_SIZE ? NULL : &l2tab[pos];
584 }
585 
586 static void *l2t_seq_start(struct seq_file *seq, loff_t *pos)
587 {
588 	return *pos ? l2t_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
589 }
590 
591 static void *l2t_seq_next(struct seq_file *seq, void *v, loff_t *pos)
592 {
593 	v = l2t_get_idx(seq, *pos);
594 	if (v)
595 		++*pos;
596 	return v;
597 }
598 
599 static void l2t_seq_stop(struct seq_file *seq, void *v)
600 {
601 }
602 
603 static char l2e_state(const struct l2t_entry *e)
604 {
605 	switch (e->state) {
606 	case L2T_STATE_VALID: return 'V';
607 	case L2T_STATE_STALE: return 'S';
608 	case L2T_STATE_SYNC_WRITE: return 'W';
609 	case L2T_STATE_RESOLVING: return e->arpq_head ? 'A' : 'R';
610 	case L2T_STATE_SWITCHING: return 'X';
611 	default:
612 		return 'U';
613 	}
614 }
615 
616 static int l2t_seq_show(struct seq_file *seq, void *v)
617 {
618 	if (v == SEQ_START_TOKEN)
619 		seq_puts(seq, " Idx IP address                "
620 			 "Ethernet address  VLAN/P LP State Users Port\n");
621 	else {
622 		char ip[60];
623 		struct l2t_entry *e = v;
624 
625 		spin_lock_bh(&e->lock);
626 		if (e->state == L2T_STATE_SWITCHING)
627 			ip[0] = '\0';
628 		else
629 			sprintf(ip, e->v6 ? "%pI6c" : "%pI4", e->addr);
630 		seq_printf(seq, "%4u %-25s %17pM %4d %u %2u   %c   %5u %s\n",
631 			   e->idx, ip, e->dmac,
632 			   e->vlan & VLAN_VID_MASK, vlan_prio(e), e->lport,
633 			   l2e_state(e), atomic_read(&e->refcnt),
634 			   e->neigh ? e->neigh->dev->name : "");
635 		spin_unlock_bh(&e->lock);
636 	}
637 	return 0;
638 }
639 
640 static const struct seq_operations l2t_seq_ops = {
641 	.start = l2t_seq_start,
642 	.next = l2t_seq_next,
643 	.stop = l2t_seq_stop,
644 	.show = l2t_seq_show
645 };
646 
647 static int l2t_seq_open(struct inode *inode, struct file *file)
648 {
649 	int rc = seq_open(file, &l2t_seq_ops);
650 
651 	if (!rc) {
652 		struct adapter *adap = inode->i_private;
653 		struct seq_file *seq = file->private_data;
654 
655 		seq->private = adap->l2t->l2tab;
656 	}
657 	return rc;
658 }
659 
660 const struct file_operations t4_l2t_fops = {
661 	.owner = THIS_MODULE,
662 	.open = l2t_seq_open,
663 	.read = seq_read,
664 	.llseek = seq_lseek,
665 	.release = seq_release,
666 };
667