[openib-general] [PATCH v2 12/14] CXGB3 Core L2 Management.
Steve Wise
swise at opengridcomputing.com
Fri Jun 23 07:30:26 PDT 2006
This code manages the hardware's neighbour table and thus hooks into the
native L2/L3 stack. Currently we're using the Netevent Notifier Mechanism
patch to detect neighbour changes. This needs more discussion on how
RNICs should be made aware of next hop changes...
ISSUE: The processing of notification of L2/L3 events should really be
in the IWCM, and an interface defined between the IWCM and IW devices to
pass pertinent events down to the device. Currently, this is all done
in the cxgb3c module since there are no other open source iwarp drivers
that need this.
---
drivers/infiniband/hw/cxgb3/t3c/l2t.c | 616 +++++++++++++++++++++++++++++++++
drivers/infiniband/hw/cxgb3/t3c/l2t.h | 147 ++++++++
2 files changed, 763 insertions(+), 0 deletions(-)
diff --git a/drivers/infiniband/hw/cxgb3/t3c/l2t.c b/drivers/infiniband/hw/cxgb3/t3c/l2t.c
new file mode 100644
index 0000000..7912950
--- /dev/null
+++ b/drivers/infiniband/hw/cxgb3/t3c/l2t.c
@@ -0,0 +1,616 @@
+/*
+ * Copyright (c) 2006 Chelsio, Inc. All rights reserved.
+ * Copyright (c) 2006 Open Grid Computing, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * - 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.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/if.h>
+#include <linux/if_vlan.h>
+#include <linux/jhash.h>
+#include <net/neighbour.h>
+#include "t3cdev.h"
+#include "defs.h"
+#include "l2t.h"
+#include "t3_cpl.h"
+#include "firmware_exports.h"
+
+/* #define L2T_DEBUG */
+
+#ifdef L2T_DEBUG
+#define dprintk(fmt, args...) do {printk(KERN_INFO fmt, ##args);} while (0)
+#else
+#define dprintk(fmt, args...) do {} while (0)
+#endif
+
+
+#define VLAN_NONE 0xfff
+
+/*
+ * Module locking notes: There is a RW lock protecting the L2 table as a
+ * whole plus a spinlock per L2T entry. Entry lookups and allocations happen
+ * under the protection of the table lock, individual entry changes happen
+ * while holding that entry's spinlock. The table lock nests outside the
+ * entry locks. Allocations of new entries take the table lock as writers so
+ * no other lookups can happen while allocating new entries. Entry updates
+ * take the table lock as readers so multiple entries can be updated in
+ * parallel. An L2T entry can be dropped by decrementing its reference count
+ * and therefore can happen in parallel with entry allocation but no entry
+ * can change state or increment its ref count during allocation as both of
+ * these perform lookups.
+ *
+ * Note: We do not take refereces to net_devices in this module because both
+ * the TOE and the sockets already hold references to the interfaces and the
+ * lifetime of an L2T entry is fully contained in the lifetime of the TOE.
+ */
+
+static inline unsigned int vlan_prio(const struct l2t_entry *e)
+{
+ return e->vlan >> 13;
+}
+
+static inline unsigned int arp_hash(u32 key, int ifindex,
+ const struct l2t_data *d)
+{
+ return jhash_2words(key, ifindex, 0) & (d->nentries - 1);
+}
+
+static inline void neigh_replace(struct l2t_entry *e, struct neighbour *n)
+{
+ dprintk("%s %d e %p e->neigh %p neigh %p\n", __FUNCTION__, __LINE__,
+ e, e->neigh, n);
+ neigh_hold(n);
+ if (e->neigh)
+ neigh_release(e->neigh);
+ e->neigh = n;
+}
+
+/*
+ * Set up an L2T entry and send any packets waiting in the arp queue. The
+ * supplied skb is used for the CPL_L2T_WRITE_REQ. Must be called with the
+ * entry locked.
+ */
+static int setup_l2e_send_pending(struct t3cdev *dev, struct sk_buff *skb,
+ struct l2t_entry *e)
+{
+ struct cpl_l2t_write_req *req;
+
+ if (!skb) {
+ skb = alloc_skb(sizeof(*req), GFP_ATOMIC);
+ if (!skb)
+ return -ENOMEM;
+ }
+
+ dprintk("%s %d e %p neigh %p\n", __FUNCTION__, __LINE__, e,
+ e->neigh);
+ req = (struct cpl_l2t_write_req *)__skb_put(skb, sizeof(*req));
+ req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
+ OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ, e->idx));
+ req->params = htonl(V_L2T_W_IDX(e->idx) | V_L2T_W_IFF(e->smt_idx) |
+ V_L2T_W_VLAN(e->vlan & VLAN_VID_MASK) |
+ V_L2T_W_PRIO(vlan_prio(e)));
+ memcpy(e->dmac, e->neigh->ha, sizeof(e->dmac));
+ memcpy(req->dst_mac, e->dmac, sizeof(req->dst_mac));
+ dprintk("%s updating HW idx %d with %02x:%02x:%02x:%02x:%02x:%02x\n",
+ __FUNCTION__, e->idx,
+ req->dst_mac[0],
+ req->dst_mac[1],
+ req->dst_mac[2],
+ req->dst_mac[3],
+ req->dst_mac[4],
+ req->dst_mac[5]);
+ skb->priority = CPL_PRIORITY_CONTROL;
+ t3c_send(dev, skb);
+ while (e->arpq_head) {
+ skb = e->arpq_head;
+ e->arpq_head = skb->next;
+ skb->next = NULL;
+ t3c_send(dev, skb);
+ }
+ e->arpq_tail = NULL;
+ e->state = L2T_STATE_VALID;
+
+ return 0;
+}
+
+/*
+ * Add a packet to the an L2T entry's queue of packets awaiting resolution.
+ * Must be called with the entry's lock held.
+ */
+static inline void arpq_enqueue(struct l2t_entry *e, struct sk_buff *skb)
+{
+ dprintk("%s %d e %p neigh %p\n", __FUNCTION__, __LINE__, e, e->neigh);
+ skb->next = NULL;
+ if (e->arpq_head)
+ e->arpq_tail->next = skb;
+ else
+ e->arpq_head = skb;
+ e->arpq_tail = skb;
+}
+
+int t3_l2t_send_slow(struct t3cdev *dev, struct sk_buff *skb,
+ struct l2t_entry *e)
+{
+again:
+ switch (e->state) {
+ case L2T_STATE_STALE: /* entry is stale, kick off revalidation */
+ dprintk("%s %d STALE - e %p neigh %p\n", __FUNCTION__,
+ __LINE__, e, e->neigh);
+ neigh_event_send(e->neigh, NULL);
+ spin_lock_bh(&e->lock);
+ if (e->state == L2T_STATE_STALE)
+ e->state = L2T_STATE_VALID;
+ spin_unlock_bh(&e->lock);
+ case L2T_STATE_VALID: /* fast-path, send the packet on */
+ return t3c_send(dev, skb);
+ case L2T_STATE_RESOLVING:
+ spin_lock_bh(&e->lock);
+ if (e->state != L2T_STATE_RESOLVING) { // ARP already completed
+ spin_unlock_bh(&e->lock);
+ goto again;
+ }
+ dprintk("%s %d RESOLVING - e %p neigh %p\n", __FUNCTION__,
+ __LINE__, e, e->neigh);
+ arpq_enqueue(e, skb);
+ spin_unlock_bh(&e->lock);
+
+ /*
+ * Only the first packet added to the arpq should kick off
+ * resolution. However, because the alloc_skb below can fail,
+ * we allow each packet added to the arpq to retry resolution
+ * as a way of recovering from transient memory exhaustion.
+ * A better way would be to use a work request to retry L2T
+ * entries when there's no memory.
+ */
+ if (!neigh_event_send(e->neigh, NULL)) {
+ skb = alloc_skb(sizeof(struct cpl_l2t_write_req),
+ GFP_ATOMIC);
+ if (!skb)
+ break;
+
+ spin_lock_bh(&e->lock);
+ if (e->arpq_head)
+ setup_l2e_send_pending(dev, skb, e);
+ else /* we lost the race */
+ __kfree_skb(skb);
+ spin_unlock_bh(&e->lock);
+ }
+ }
+ return 0;
+}
+EXPORT_SYMBOL(t3_l2t_send_slow);
+
+void t3_l2t_send_event(struct t3cdev *dev, struct l2t_entry *e)
+{
+ dprintk("%s l2t %p neigh %p nud_state %x\n", __FUNCTION__, e,
+ e->neigh, e->neigh->nud_state);
+
+again:
+ switch (e->state) {
+ case L2T_STATE_STALE: /* entry is stale, kick off revalidation */
+ dprintk("%s %d STALE - e %p neigh %p\n", __FUNCTION__,
+ __LINE__, e, e->neigh);
+ neigh_event_send(e->neigh, NULL);
+ spin_lock_bh(&e->lock);
+ if (e->state == L2T_STATE_STALE) {
+ e->state = L2T_STATE_VALID;
+ dprintk("%s STALE->VALID!\n", __FUNCTION__);
+ }
+ spin_unlock_bh(&e->lock);
+ return;
+ case L2T_STATE_VALID: /* fast-path, send the packet on */
+ dprintk("%s %d VALID - e %p neigh %p\n", __FUNCTION__,
+ __LINE__, e, e->neigh);
+ return;
+ case L2T_STATE_RESOLVING:
+ spin_lock_bh(&e->lock);
+ if (e->state != L2T_STATE_RESOLVING) { // ARP already completed
+ spin_unlock_bh(&e->lock);
+ goto again;
+ }
+ dprintk("%s %d RESOLVING - e %p neigh %p\n", __FUNCTION__,
+ __LINE__, e, e->neigh);
+ spin_unlock_bh(&e->lock);
+
+ /*
+ * Only the first packet added to the arpq should kick off
+ * resolution. However, because the alloc_skb below can fail,
+ * we allow each packet added to the arpq to retry resolution
+ * as a way of recovering from transient memory exhaustion.
+ * A better way would be to use a work request to retry L2T
+ * entries when there's no memory.
+ */
+ neigh_event_send(e->neigh, NULL);
+ }
+ return;
+}
+EXPORT_SYMBOL(t3_l2t_send_event);
+
+/*
+ * Allocate a free L2T entry. Must be called with l2t_data.lock held.
+ */
+static struct l2t_entry *alloc_l2e(struct l2t_data *d)
+{
+ struct l2t_entry *end, *e, **p;
+
+ if (!atomic_read(&d->nfree))
+ return NULL;
+
+ /* there's definitely a free entry */
+ for (e = d->rover, end = &d->l2tab[d->nentries]; e != end; ++e)
+ if (atomic_read(&e->refcnt) == 0)
+ goto found;
+
+ for (e = &d->l2tab[1]; atomic_read(&e->refcnt); ++e) ;
+found:
+ d->rover = e + 1;
+ atomic_dec(&d->nfree);
+
+ /*
+ * The entry we found may be an inactive entry that is
+ * presently in the hash table. We need to remove it.
+ */
+ if (e->state != L2T_STATE_UNUSED) {
+ int hash = arp_hash(e->addr, e->ifindex, d);
+
+ for (p = &d->l2tab[hash].first; *p; p = &(*p)->next)
+ if (*p == e) {
+ *p = e->next;
+ break;
+ }
+ e->state = L2T_STATE_UNUSED;
+ }
+ dprintk("%s %d e %p neigh %p\n", __FUNCTION__, __LINE__, e, e->neigh);
+ return e;
+}
+
+/*
+ * Called when an L2T entry has no more users. The entry is left in the hash
+ * table since it is likely to be reused but we also bump nfree to indicate
+ * that the entry can be reallocated for a different neighbor. We also drop
+ * the existing neighbor reference in case the neighbor is going away and is
+ * waiting on our reference.
+ *
+ * Because entries can be reallocated to other neighbors once their ref count
+ * drops to 0 we need to take the entry's lock to avoid races with a new
+ * incarnation.
+ */
+void t3_l2e_free(struct l2t_data *d, struct l2t_entry *e)
+{
+ spin_lock_bh(&e->lock);
+ if (atomic_read(&e->refcnt) == 0) { /* hasn't been recycled */
+ dprintk("%s %d e %p neigh %p\n", __FUNCTION__, __LINE__,
+ e, e->neigh);
+ if (e->neigh) {
+ neigh_release(e->neigh);
+ e->neigh = NULL;
+ }
+ /*
+ * Don't need to worry about the arpq, an L2T entry can't be
+ * released if any packets are waiting for resolution as we
+ * need to be able to communicate with the TOE to close a
+ * connection.
+ */
+ }
+ spin_unlock_bh(&e->lock);
+ atomic_inc(&d->nfree);
+}
+EXPORT_SYMBOL(t3_l2e_free);
+
+/*
+ * Update an L2T entry that was previously used for the same next hop as neigh.
+ * Must be called with softirqs disabled.
+ */
+static inline void reuse_entry(struct l2t_entry *e, struct neighbour *neigh)
+{
+ unsigned int nud_state;
+
+ spin_lock(&e->lock); /* avoid race with t3_l2t_free */
+ dprintk("%s %d e %p neigh %p\n", __FUNCTION__, __LINE__, e, neigh);
+
+ if (neigh != e->neigh)
+ neigh_replace(e, neigh);
+ nud_state = neigh->nud_state;
+ if (memcmp(e->dmac, neigh->ha, sizeof(e->dmac)) ||
+ !(nud_state & NUD_VALID))
+ e->state = L2T_STATE_RESOLVING;
+ else if (nud_state & NUD_CONNECTED)
+ e->state = L2T_STATE_VALID;
+ else
+ e->state = L2T_STATE_STALE;
+ spin_unlock(&e->lock);
+}
+
+struct l2t_entry *t3_l2t_get(struct t3cdev *dev, struct neighbour *neigh,
+ unsigned int smt_idx)
+{
+ struct l2t_entry *e;
+ struct l2t_data *d = L2DATA(dev);
+ u32 addr = *(u32 *) neigh->primary_key;
+ int ifidx = neigh->dev->ifindex;
+ int hash = arp_hash(addr, ifidx, d);
+
+ write_lock_bh(&d->lock);
+ for (e = d->l2tab[hash].first; e; e = e->next)
+ if (e->addr == addr && e->ifindex == ifidx &&
+ e->smt_idx == smt_idx) {
+ l2t_hold(d, e);
+ if (atomic_read(&e->refcnt) == 1)
+ reuse_entry(e, neigh);
+ goto done;
+ }
+
+ /* Need to allocate a new entry */
+ e = alloc_l2e(d);
+ if (e) {
+ spin_lock(&e->lock); /* avoid race with t3_l2t_free */
+ e->next = d->l2tab[hash].first;
+ d->l2tab[hash].first = e;
+ e->state = L2T_STATE_RESOLVING;
+ e->addr = addr;
+ e->ifindex = ifidx;
+ e->smt_idx = smt_idx;
+ atomic_set(&e->refcnt, 1);
+ neigh_replace(e, neigh);
+ if (neigh->dev->priv_flags & IFF_802_1Q_VLAN)
+ e->vlan = VLAN_DEV_INFO(neigh->dev)->vlan_id;
+ else
+ e->vlan = VLAN_NONE;
+ spin_unlock(&e->lock);
+ }
+done:
+ dprintk("%s %d e %p neigh %p\n", __FUNCTION__, __LINE__, e, neigh);
+ write_unlock_bh(&d->lock);
+ return e;
+}
+EXPORT_SYMBOL(t3_l2t_get);
+
+/*
+ * Called when address resolution fails for an L2T entry to handle packets
+ * on the arpq head. If a packet specifies a failure handler it is invoked,
+ * otherwise the packets is sent to the TOE.
+ *
+ * XXX: maybe we should abandon the latter behavior and just require a failure
+ * handler.
+ */
+static void handle_failed_resolution(struct t3cdev *dev, struct sk_buff *arpq)
+{
+ while (arpq) {
+ struct sk_buff *skb = arpq;
+ struct l2t_skb_cb *cb = L2T_SKB_CB(skb);
+
+ arpq = skb->next;
+ skb->next = NULL;
+ if (cb->arp_failure_handler)
+ cb->arp_failure_handler(dev, skb);
+ else
+ t3c_send(dev, skb);
+ }
+}
+
+/*
+ * Called when the host's ARP layer makes a change to some entry that is
+ * loaded into the HW L2 table.
+ */
+void t3_l2t_update(struct t3cdev *dev, struct neighbour *neigh, int flags, struct net_device *lldev)
+{
+ struct l2t_entry *e;
+ struct sk_buff *arpq = NULL;
+ struct l2t_data *d = L2DATA(dev);
+ u32 addr = *(u32 *) neigh->primary_key;
+ int ifidx = neigh->dev->ifindex;
+ int hash = arp_hash(addr, ifidx, d);
+
+ read_lock_bh(&d->lock);
+ for (e = d->l2tab[hash].first; e; e = e->next)
+ if (e->addr == addr && e->ifindex == ifidx) {
+ spin_lock(&e->lock);
+ goto found;
+ }
+ read_unlock_bh(&d->lock);
+ return;
+
+found:
+ dprintk("%s l2t %p neigh %p nud_state %x\n", __FUNCTION__, e,
+ e->neigh, e->neigh ? e->neigh->nud_state : -1);
+ read_unlock(&d->lock);
+ if (atomic_read(&e->refcnt)) {
+ if (neigh != e->neigh)
+ neigh_replace(e, neigh);
+
+ if (e->state == L2T_STATE_RESOLVING) {
+ dprintk("%s %d RESOLVING - e %p neigh %p\n",
+ __FUNCTION__, __LINE__, e, e->neigh);
+ if (neigh->nud_state & NUD_FAILED) {
+ arpq = e->arpq_head;
+ e->arpq_head = e->arpq_tail = NULL;
+ } else if (neigh_is_connected(neigh))
+ setup_l2e_send_pending(dev, NULL, e);
+ } else {
+ e->state = neigh_is_connected(neigh) ?
+ L2T_STATE_VALID : L2T_STATE_STALE;
+ dprintk("%s %d state -> %d - e %p neigh %p\n",
+ __FUNCTION__, __LINE__, e->state,
+ e, e->neigh);
+ if (memcmp(e->dmac, neigh->ha, 6))
+ setup_l2e_send_pending(dev, NULL, e);
+ }
+ }
+ spin_unlock_bh(&e->lock);
+
+ if (arpq)
+ handle_failed_resolution(dev, arpq);
+}
+
+struct l2t_data *t3_init_l2t(unsigned int l2t_capacity)
+{
+ struct l2t_data *d;
+ int i, size = sizeof(*d) + l2t_capacity * sizeof(struct l2t_entry);
+
+ d = t3_alloc_mem(size);
+ if (!d)
+ return NULL;
+
+ d->nentries = l2t_capacity;
+ d->rover = &d->l2tab[1]; /* entry 0 is not used */
+ atomic_set(&d->nfree, l2t_capacity - 1);
+ rwlock_init(&d->lock);
+
+ for (i = 0; i < l2t_capacity; ++i) {
+ d->l2tab[i].idx = i;
+ d->l2tab[i].state = L2T_STATE_UNUSED;
+ spin_lock_init(&d->l2tab[i].lock);
+ atomic_set(&d->l2tab[i].refcnt, 0);
+ }
+ return d;
+}
+
+void t3_free_l2t(struct l2t_data *d)
+{
+ t3_free_mem(d);
+}
+
+#ifdef CONFIG_PROC_FS
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+static inline void *l2t_get_idx(struct seq_file *seq, loff_t pos)
+{
+ struct l2t_data *d = seq->private;
+
+ return pos >= d->nentries ? NULL : &d->l2tab[pos];
+}
+
+static void *l2t_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ return *pos ? l2t_get_idx(seq, *pos) : SEQ_START_TOKEN;
+}
+
+static void *l2t_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ v = l2t_get_idx(seq, *pos + 1);
+ if (v)
+ ++*pos;
+ return v;
+}
+
+static void l2t_seq_stop(struct seq_file *seq, void *v)
+{
+}
+
+static char l2e_state(const struct l2t_entry *e)
+{
+ switch (e->state) {
+ case L2T_STATE_VALID: return 'V'; /* valid, fast-path entry */
+ case L2T_STATE_STALE: return 'S'; /* needs revalidation, but usable */
+ case L2T_STATE_RESOLVING:
+ return e->arpq_head ? 'A' : 'R';
+ default:
+ return 'U';
+ }
+}
+
+static int l2t_seq_show(struct seq_file *seq, void *v)
+{
+ if (v == SEQ_START_TOKEN)
+ seq_puts(seq, "Index IP address Ethernet address VLAN "
+ "Prio State Users SMTIDX Port\n");
+ else {
+ char ip[20];
+ struct l2t_entry *e = v;
+
+ spin_lock_bh(&e->lock);
+ sprintf(ip, "%u.%u.%u.%u", NIPQUAD(e->addr));
+ seq_printf(seq, "%-5u %-15s %02x:%02x:%02x:%02x:%02x:%02x %4d"
+ " %3u %c %7u %4u %s\n",
+ e->idx, ip, e->dmac[0], e->dmac[1], e->dmac[2],
+ e->dmac[3], e->dmac[4], e->dmac[5],
+ e->vlan & VLAN_VID_MASK, vlan_prio(e),
+ l2e_state(e), atomic_read(&e->refcnt), e->smt_idx,
+ e->neigh ? e->neigh->dev->name : "");
+ spin_unlock_bh(&e->lock);
+ }
+ return 0;
+}
+
+static struct seq_operations l2t_seq_ops = {
+ .start = l2t_seq_start,
+ .next = l2t_seq_next,
+ .stop = l2t_seq_stop,
+ .show = l2t_seq_show
+};
+
+static int l2t_seq_open(struct inode *inode, struct file *file)
+{
+ int rc = seq_open(file, &l2t_seq_ops);
+
+ if (!rc) {
+ struct proc_dir_entry *dp = PDE(inode);
+ struct seq_file *seq = file->private_data;
+
+ seq->private = dp->data;
+ }
+ return rc;
+}
+
+static struct file_operations l2t_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = l2t_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+/*
+ * Create the proc entries for the L2 table under dir.
+ */
+int t3_l2t_proc_setup(struct proc_dir_entry *dir, struct l2t_data *d)
+{
+ struct proc_dir_entry *p;
+
+ if (!dir)
+ return -EINVAL;
+
+ p = create_proc_entry("l2t", S_IRUGO, dir);
+ if (!p)
+ return -ENOMEM;
+
+ p->proc_fops = &l2t_seq_fops;
+ p->data = d;
+ return 0;
+}
+
+void t3_l2t_proc_free(struct proc_dir_entry *dir)
+{
+ if (dir)
+ remove_proc_entry("l2t", dir);
+}
+#endif
diff --git a/drivers/infiniband/hw/cxgb3/t3c/l2t.h b/drivers/infiniband/hw/cxgb3/t3c/l2t.h
new file mode 100644
index 0000000..48a247f
--- /dev/null
+++ b/drivers/infiniband/hw/cxgb3/t3c/l2t.h
@@ -0,0 +1,147 @@
+/*
+ * Copyright (c) 2006 Chelsio, Inc. All rights reserved.
+ * Copyright (c) 2006 Open Grid Computing, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * - 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.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#ifndef _CHELSIO_L2T_H
+#define _CHELSIO_L2T_H
+
+#include <linux/config.h>
+#include <linux/spinlock.h>
+#include "t3cdev.h"
+#include <asm/atomic.h>
+
+enum {
+ L2T_STATE_VALID, /* entry is up to date */
+ L2T_STATE_STALE, /* entry may be used but needs revalidation */
+ L2T_STATE_RESOLVING, /* entry needs address resolution */
+ L2T_STATE_UNUSED /* entry not in use */
+};
+
+struct neighbour;
+struct sk_buff;
+
+/*
+ * Each L2T entry plays multiple roles. First of all, it keeps state for the
+ * corresponding entry of the HW L2 table and maintains a queue of offload
+ * packets awaiting address resolution. Second, it is a node of a hash table
+ * chain, where the nodes of the chain are linked together through their next
+ * pointer. Finally, each node is a bucket of a hash table, pointing to the
+ * first element in its chain through its first pointer.
+ */
+struct l2t_entry {
+ u16 state; /* entry state */
+ u16 idx; /* entry index */
+ u32 addr; /* dest IP address */
+ int ifindex; /* neighbor's net_device's ifindex */
+ u16 smt_idx; /* SMT index */
+ u16 vlan; /* VLAN TCI (id: bits 0-11, prio: 13-15 */
+ struct neighbour *neigh; /* associated neighbour */
+ struct l2t_entry *first; /* start of hash chain */
+ struct l2t_entry *next; /* next l2t_entry on chain */
+ struct sk_buff *arpq_head; /* queue of packets awaiting resolution */
+ struct sk_buff *arpq_tail;
+ spinlock_t lock;
+ atomic_t refcnt; /* entry reference count */
+ u8 dmac[6]; /* neighbour's MAC address */
+};
+
+struct l2t_data {
+ unsigned int nentries; /* number of entries */
+ struct l2t_entry *rover; /* starting point for next allocation */
+ atomic_t nfree; /* number of free entries */
+ rwlock_t lock;
+ struct l2t_entry l2tab[0];
+};
+
+typedef void (*arp_failure_handler_func)(struct t3cdev *dev,
+ struct sk_buff *skb);
+
+/*
+ * Callback stored in an skb to handle address resolution failure.
+ */
+struct l2t_skb_cb {
+ arp_failure_handler_func arp_failure_handler;
+};
+
+#define L2T_SKB_CB(skb) ((struct l2t_skb_cb *)(skb)->cb)
+
+static inline void set_arp_failure_handler(struct sk_buff *skb,
+ arp_failure_handler_func hnd)
+{
+ L2T_SKB_CB(skb)->arp_failure_handler = hnd;
+}
+
+/*
+ * Getting to the L2 data from a toe device.
+ */
+#define L2DATA(dev) ((dev)->l2opt)
+
+void t3_l2e_free(struct l2t_data *d, struct l2t_entry *e);
+void t3_l2t_update(struct t3cdev *dev, struct neighbour *neigh, int flags, struct net_device *lldev);
+struct l2t_entry *t3_l2t_get(struct t3cdev *dev, struct neighbour *neigh,
+ unsigned int smt_idx);
+int t3_l2t_send_slow(struct t3cdev *dev, struct sk_buff *skb,
+ struct l2t_entry *e);
+void t3_l2t_send_event(struct t3cdev *dev, struct l2t_entry *e);
+struct l2t_data *t3_init_l2t(unsigned int l2t_capacity);
+void t3_free_l2t(struct l2t_data *d);
+
+#ifdef CONFIG_PROC_FS
+int t3_l2t_proc_setup(struct proc_dir_entry *dir, struct l2t_data *d);
+void t3_l2t_proc_free(struct proc_dir_entry *dir);
+#else
+#define l2t_proc_setup(dir, d) 0
+#define l2t_proc_free(dir)
+#endif
+
+int t3c_send(struct t3cdev *dev, struct sk_buff *skb);
+
+static inline int l2t_send(struct t3cdev *dev, struct sk_buff *skb,
+ struct l2t_entry *e)
+{
+ if (likely(e->state == L2T_STATE_VALID))
+ return t3c_send(dev, skb);
+ return t3_l2t_send_slow(dev, skb, e);
+}
+
+static inline void l2t_release(struct l2t_data *d, struct l2t_entry *e)
+{
+ if (atomic_dec_and_test(&e->refcnt))
+ t3_l2e_free(d, e);
+}
+
+static inline void l2t_hold(struct l2t_data *d, struct l2t_entry *e)
+{
+ if (atomic_add_return(1, &e->refcnt) == 1) /* 0 -> 1 transition */
+ atomic_dec(&d->nfree);
+}
+
+#endif
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