2  * Copyright (c) 2003-2008 Chelsio, Inc. All rights reserved.
14  *      - Redistributions of source code must retain the above
18  *      - Redistributions in binary form must reproduce the above
50  * Module locking notes:  There is a RW lock protecting the L2 table as a
52  * under the protection of the table lock, individual entry changes happen
53  * while holding that entry's spinlock.  The table lock nests outside the
54  * entry locks.  Allocations of new entries take the table lock as writers so
56  * take the table lock as readers so multiple entries can be updated in
59  * can change state or increment its ref count during allocation as both of
65 	return e->vlan >> 13;  in vlan_prio()
71 	return jhash_2words(key, ifindex, 0) & (d->nentries - 1);  in arp_hash()
77 	if (e->neigh)  in neigh_replace()
78 		neigh_release(e->neigh);  in neigh_replace()
79 	e->neigh = n;  in neigh_replace()
96 			return -ENOMEM;  in setup_l2e_send_pending()
100 	req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));  in setup_l2e_send_pending()
101 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ, e->idx));  in setup_l2e_send_pending()
102 	req->params = htonl(V_L2T_W_IDX(e->idx) | V_L2T_W_IFF(e->smt_idx) |  in setup_l2e_send_pending()
103 			    V_L2T_W_VLAN(e->vlan & VLAN_VID_MASK) |  in setup_l2e_send_pending()
105 	memcpy(e->dmac, e->neigh->ha, sizeof(e->dmac));  in setup_l2e_send_pending()
106 	memcpy(req->dst_mac, e->dmac, sizeof(req->dst_mac));  in setup_l2e_send_pending()
107 	skb->priority = CPL_PRIORITY_CONTROL;  in setup_l2e_send_pending()
110 	skb_queue_walk_safe(&e->arpq, skb, tmp) {  in setup_l2e_send_pending()
111 		__skb_unlink(skb, &e->arpq);  in setup_l2e_send_pending()
114 	e->state = L2T_STATE_VALID;  in setup_l2e_send_pending()
121  * Must be called with the entry's lock held.
125 	__skb_queue_tail(&e->arpq, skb);  in arpq_enqueue()
132 	switch (e->state) {  in t3_l2t_send_slow()
134 		neigh_event_send(e->neigh, NULL);  in t3_l2t_send_slow()
135 		spin_lock_bh(&e->lock);  in t3_l2t_send_slow()
136 		if (e->state == L2T_STATE_STALE)  in t3_l2t_send_slow()
137 			e->state = L2T_STATE_VALID;  in t3_l2t_send_slow()
138 		spin_unlock_bh(&e->lock);  in t3_l2t_send_slow()
140 	case L2T_STATE_VALID:	/* fast-path, send the packet on */  in t3_l2t_send_slow()
143 		spin_lock_bh(&e->lock);  in t3_l2t_send_slow()
144 		if (e->state != L2T_STATE_RESOLVING) {  in t3_l2t_send_slow()
146 			spin_unlock_bh(&e->lock);  in t3_l2t_send_slow()
150 		spin_unlock_bh(&e->lock);  in t3_l2t_send_slow()
160 		if (!neigh_event_send(e->neigh, NULL)) {  in t3_l2t_send_slow()
166 			spin_lock_bh(&e->lock);  in t3_l2t_send_slow()
167 			if (!skb_queue_empty(&e->arpq))  in t3_l2t_send_slow()
171 			spin_unlock_bh(&e->lock);  in t3_l2t_send_slow()
182 	switch (e->state) {  in t3_l2t_send_event()
184 		neigh_event_send(e->neigh, NULL);  in t3_l2t_send_event()
185 		spin_lock_bh(&e->lock);  in t3_l2t_send_event()
186 		if (e->state == L2T_STATE_STALE) {  in t3_l2t_send_event()
187 			e->state = L2T_STATE_VALID;  in t3_l2t_send_event()
189 		spin_unlock_bh(&e->lock);  in t3_l2t_send_event()
191 	case L2T_STATE_VALID:	/* fast-path, send the packet on */  in t3_l2t_send_event()
194 		spin_lock_bh(&e->lock);  in t3_l2t_send_event()
195 		if (e->state != L2T_STATE_RESOLVING) {  in t3_l2t_send_event()
197 			spin_unlock_bh(&e->lock);  in t3_l2t_send_event()
200 		spin_unlock_bh(&e->lock);  in t3_l2t_send_event()
210 		neigh_event_send(e->neigh, NULL);  in t3_l2t_send_event()
217  * Allocate a free L2T entry.  Must be called with l2t_data.lock held.
223 	if (!atomic_read(&d->nfree))  in alloc_l2e()
227 	for (e = d->rover, end = &d->l2tab[d->nentries]; e != end; ++e)  in alloc_l2e()
228 		if (atomic_read(&e->refcnt) == 0)  in alloc_l2e()
231 	for (e = &d->l2tab[1]; atomic_read(&e->refcnt); ++e) ;  in alloc_l2e()
233 	d->rover = e + 1;  in alloc_l2e()
234 	atomic_dec(&d->nfree);  in alloc_l2e()
240 	if (e->state != L2T_STATE_UNUSED) {  in alloc_l2e()
241 		int hash = arp_hash(e->addr, e->ifindex, d);  in alloc_l2e()
243 		for (p = &d->l2tab[hash].first; *p; p = &(*p)->next)  in alloc_l2e()
245 				*p = e->next;  in alloc_l2e()
248 		e->state = L2T_STATE_UNUSED;  in alloc_l2e()
261  * drops to 0 we need to take the entry's lock to avoid races with a new
266 	spin_lock_bh(&e->lock);  in t3_l2e_free()
267 	if (atomic_read(&e->refcnt) == 0) {	/* hasn't been recycled */  in t3_l2e_free()
268 		if (e->neigh) {  in t3_l2e_free()
269 			neigh_release(e->neigh);  in t3_l2e_free()
270 			e->neigh = NULL;  in t3_l2e_free()
273 	spin_unlock_bh(&e->lock);  in t3_l2e_free()
274 	atomic_inc(&d->nfree);  in t3_l2e_free()
287 	spin_lock(&e->lock);	/* avoid race with t3_l2t_free */  in reuse_entry()
289 	if (neigh != e->neigh)  in reuse_entry()
291 	nud_state = neigh->nud_state;  in reuse_entry()
292 	if (memcmp(e->dmac, neigh->ha, sizeof(e->dmac)) ||  in reuse_entry()
294 		e->state = L2T_STATE_RESOLVING;  in reuse_entry()
296 		e->state = L2T_STATE_VALID;  in reuse_entry()
298 		e->state = L2T_STATE_STALE;  in reuse_entry()
299 	spin_unlock(&e->lock);  in reuse_entry()
319 	addr = *(u32 *) neigh->primary_key;  in t3_l2t_get()
320 	ifidx = neigh->dev->ifindex;  in t3_l2t_get()
323 		dev = neigh->dev;  in t3_l2t_get()
325 	smt_idx = p->port_id;  in t3_l2t_get()
333 	write_lock_bh(&d->lock);  in t3_l2t_get()
334 	for (e = d->l2tab[hash].first; e; e = e->next)  in t3_l2t_get()
335 		if (e->addr == addr && e->ifindex == ifidx &&  in t3_l2t_get()
336 		    e->smt_idx == smt_idx) {  in t3_l2t_get()
338 			if (atomic_read(&e->refcnt) == 1)  in t3_l2t_get()
346 		spin_lock(&e->lock);	/* avoid race with t3_l2t_free */  in t3_l2t_get()
347 		e->next = d->l2tab[hash].first;  in t3_l2t_get()
348 		d->l2tab[hash].first = e;  in t3_l2t_get()
349 		e->state = L2T_STATE_RESOLVING;  in t3_l2t_get()
350 		e->addr = addr;  in t3_l2t_get()
351 		e->ifindex = ifidx;  in t3_l2t_get()
352 		e->smt_idx = smt_idx;  in t3_l2t_get()
353 		atomic_set(&e->refcnt, 1);  in t3_l2t_get()
355 		if (is_vlan_dev(neigh->dev))  in t3_l2t_get()
356 			e->vlan = vlan_dev_vlan_id(neigh->dev);  in t3_l2t_get()
358 			e->vlan = VLAN_NONE;  in t3_l2t_get()
359 		spin_unlock(&e->lock);  in t3_l2t_get()
362 	write_unlock_bh(&d->lock);  in t3_l2t_get()
388 		if (cb->arp_failure_handler)  in handle_failed_resolution()
389 			cb->arp_failure_handler(dev, skb);  in handle_failed_resolution()
404 	u32 addr = *(u32 *) neigh->primary_key;  in t3_l2t_update()
405 	int ifidx = neigh->dev->ifindex;  in t3_l2t_update()
408 	read_lock_bh(&d->lock);  in t3_l2t_update()
409 	for (e = d->l2tab[hash].first; e; e = e->next)  in t3_l2t_update()
410 		if (e->addr == addr && e->ifindex == ifidx) {  in t3_l2t_update()
411 			spin_lock(&e->lock);  in t3_l2t_update()
414 	read_unlock_bh(&d->lock);  in t3_l2t_update()
420 	read_unlock(&d->lock);  in t3_l2t_update()
421 	if (atomic_read(&e->refcnt)) {  in t3_l2t_update()
422 		if (neigh != e->neigh)  in t3_l2t_update()
425 		if (e->state == L2T_STATE_RESOLVING) {  in t3_l2t_update()
426 			if (neigh->nud_state & NUD_FAILED) {  in t3_l2t_update()
427 				skb_queue_splice_init(&e->arpq, &arpq);  in t3_l2t_update()
428 			} else if (neigh->nud_state & (NUD_CONNECTED|NUD_STALE))  in t3_l2t_update()
431 			e->state = neigh->nud_state & NUD_CONNECTED ?  in t3_l2t_update()
433 			if (!ether_addr_equal(e->dmac, neigh->ha))  in t3_l2t_update()
437 	spin_unlock_bh(&e->lock);  in t3_l2t_update()
452 	d->nentries = l2t_capacity;  in t3_init_l2t()
453 	d->rover = &d->l2tab[1];	/* entry 0 is not used */  in t3_init_l2t()
454 	atomic_set(&d->nfree, l2t_capacity - 1);  in t3_init_l2t()
455 	rwlock_init(&d->lock);  in t3_init_l2t()
458 		d->l2tab[i].idx = i;  in t3_init_l2t()
459 		d->l2tab[i].state = L2T_STATE_UNUSED;  in t3_init_l2t()
460 		__skb_queue_head_init(&d->l2tab[i].arpq);  in t3_init_l2t()
461 		spin_lock_init(&d->l2tab[i].lock);  in t3_init_l2t()
462 		atomic_set(&d->l2tab[i].refcnt, 0);  in t3_init_l2t()