drivers/net/cxgb3/cxgb3_offload.c

/*
 * Copyright (c) 2006-2007 Chelsio, 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/list.h>
#include <net/neighbour.h>
#include <linux/notifier.h>
#include <asm/atomic.h>
#include <linux/proc_fs.h>
#include <linux/if_vlan.h>
#include <net/netevent.h>
#include <linux/highmem.h>
#include <linux/vmalloc.h>

#include "common.h"
#include "regs.h"
#include "cxgb3_ioctl.h"
#include "cxgb3_ctl_defs.h"
#include "cxgb3_defs.h"
#include "l2t.h"
#include "firmware_exports.h"
#include "cxgb3_offload.h"

static LIST_HEAD(client_list);
static LIST_HEAD(ofld_dev_list);
static DEFINE_MUTEX(cxgb3_db_lock);

static DEFINE_RWLOCK(adapter_list_lock);
static LIST_HEAD(adapter_list);

static const unsigned int MAX_ATIDS = 64 * 1024;
static const unsigned int ATID_BASE = 0x10000;

static inline int offload_activated(struct t3cdev *tdev)
{
	const struct adapter *adapter = tdev2adap(tdev);

	return (test_bit(OFFLOAD_DEVMAP_BIT, &adapter->open_device_map));
}

/**
 *	cxgb3_register_client - register an offload client
 *	@client: the client
 *
 *	Add the client to the client list,
 *	and call backs the client for each activated offload device
 */
void cxgb3_register_client(struct cxgb3_client *client)
{
	struct t3cdev *tdev;

	mutex_lock(&cxgb3_db_lock);
	list_add_tail(&client->client_list, &client_list);

	if (client->add) {
		list_for_each_entry(tdev, &ofld_dev_list, ofld_dev_list) {
			if (offload_activated(tdev))
				client->add(tdev);
		}
	}
	mutex_unlock(&cxgb3_db_lock);
}

EXPORT_SYMBOL(cxgb3_register_client);

/**
 *	cxgb3_unregister_client - unregister an offload client
 *	@client: the client
 *
 *	Remove the client to the client list,
 *	and call backs the client for each activated offload device.
 */
void cxgb3_unregister_client(struct cxgb3_client *client)
{
	struct t3cdev *tdev;

	mutex_lock(&cxgb3_db_lock);
	list_del(&client->client_list);

	if (client->remove) {
		list_for_each_entry(tdev, &ofld_dev_list, ofld_dev_list) {
			if (offload_activated(tdev))
				client->remove(tdev);
		}
	}
	mutex_unlock(&cxgb3_db_lock);
}

EXPORT_SYMBOL(cxgb3_unregister_client);

/**
 *	cxgb3_add_clients - activate registered clients for an offload device
 *	@tdev: the offload device
 *
 *	Call backs all registered clients once a offload device is activated
 */
void cxgb3_add_clients(struct t3cdev *tdev)
{
	struct cxgb3_client *client;

	mutex_lock(&cxgb3_db_lock);
	list_for_each_entry(client, &client_list, client_list) {
		if (client->add)
			client->add(tdev);
	}
	mutex_unlock(&cxgb3_db_lock);
}

/**
 *	cxgb3_remove_clients - deactivates registered clients
 *			       for an offload device
 *	@tdev: the offload device
 *
 *	Call backs all registered clients once a offload device is deactivated
 */
void cxgb3_remove_clients(struct t3cdev *tdev)
{
	struct cxgb3_client *client;

	mutex_lock(&cxgb3_db_lock);
	list_for_each_entry(client, &client_list, client_list) {
		if (client->remove)
			client->remove(tdev);
	}
	mutex_unlock(&cxgb3_db_lock);
}

static struct net_device *get_iff_from_mac(struct adapter *adapter,
					   const unsigned char *mac,
					   unsigned int vlan)
{
	int i;

	for_each_port(adapter, i) {
		struct vlan_group *grp;
		struct net_device *dev = adapter->port[i];
		const struct port_info *p = netdev_priv(dev);

		if (!memcmp(dev->dev_addr, mac, ETH_ALEN)) {
			if (vlan && vlan != VLAN_VID_MASK) {
				grp = p->vlan_grp;
				dev = NULL;
				if (grp)
					dev = vlan_group_get_device(grp, vlan);
			} else
				while (dev->master)
					dev = dev->master;
			return dev;
		}
	}
	return NULL;
}

static int cxgb_ulp_iscsi_ctl(struct adapter *adapter, unsigned int req,
			      void *data)
{
	int ret = 0;
	struct ulp_iscsi_info *uiip = data;

	switch (req) {
	case ULP_ISCSI_GET_PARAMS:
		uiip->pdev = adapter->pdev;
		uiip->llimit = t3_read_reg(adapter, A_ULPRX_ISCSI_LLIMIT);
		uiip->ulimit = t3_read_reg(adapter, A_ULPRX_ISCSI_ULIMIT);
		uiip->tagmask = t3_read_reg(adapter, A_ULPRX_ISCSI_TAGMASK);
		/*
		 * On tx, the iscsi pdu has to be <= tx page size and has to
		 * fit into the Tx PM FIFO.
		 */
		uiip->max_txsz = min(adapter->params.tp.tx_pg_size,
				     t3_read_reg(adapter, A_PM1_TX_CFG) >> 17);
		/* on rx, the iscsi pdu has to be < rx page size and the
		   whole pdu + cpl headers has to fit into one sge buffer */
		uiip->max_rxsz = min_t(unsigned int,
				       adapter->params.tp.rx_pg_size,
				       (adapter->sge.qs[0].fl[1].buf_size -
					sizeof(struct cpl_rx_data) * 2 -
					sizeof(struct cpl_rx_data_ddp)));
		break;
	case ULP_ISCSI_SET_PARAMS:
		t3_write_reg(adapter, A_ULPRX_ISCSI_TAGMASK, uiip->tagmask);
		break;
	default:
		ret = -EOPNOTSUPP;
	}
	return ret;
}

/* Response queue used for RDMA events. */
#define ASYNC_NOTIF_RSPQ 0

static int cxgb_rdma_ctl(struct adapter *adapter, unsigned int req, void *data)
{
	int ret = 0;

	switch (req) {
	case RDMA_GET_PARAMS: {
		struct rdma_info *rdma = data;
		struct pci_dev *pdev = adapter->pdev;

		rdma->udbell_physbase = pci_resource_start(pdev, 2);
		rdma->udbell_len = pci_resource_len(pdev, 2);
		rdma->tpt_base =
			t3_read_reg(adapter, A_ULPTX_TPT_LLIMIT);
		rdma->tpt_top = t3_read_reg(adapter, A_ULPTX_TPT_ULIMIT);
		rdma->pbl_base =
			t3_read_reg(adapter, A_ULPTX_PBL_LLIMIT);
		rdma->pbl_top = t3_read_reg(adapter, A_ULPTX_PBL_ULIMIT);
		rdma->rqt_base = t3_read_reg(adapter, A_ULPRX_RQ_LLIMIT);
		rdma->rqt_top = t3_read_reg(adapter, A_ULPRX_RQ_ULIMIT);
		rdma->kdb_addr = adapter->regs + A_SG_KDOORBELL;
		rdma->pdev = pdev;
		break;
	}
	case RDMA_CQ_OP:{
		unsigned long flags;
		struct rdma_cq_op *rdma = data;

		/* may be called in any context */
		spin_lock_irqsave(&adapter->sge.reg_lock, flags);
		ret = t3_sge_cqcntxt_op(adapter, rdma->id, rdma->op,
					rdma->credits);
		spin_unlock_irqrestore(&adapter->sge.reg_lock, flags);
		break;
	}
	case RDMA_GET_MEM:{
		struct ch_mem_range *t = data;
		struct mc7 *mem;

		if ((t->addr & 7) || (t->len & 7))
			return -EINVAL;
		if (t->mem_id == MEM_CM)
			mem = &adapter->cm;
		else if (t->mem_id == MEM_PMRX)
			mem = &adapter->pmrx;
		else if (t->mem_id == MEM_PMTX)
			mem = &adapter->pmtx;
		else
			return -EINVAL;

		ret =
			t3_mc7_bd_read(mem, t->addr / 8, t->len / 8,
					(u64 *) t->buf);
		if (ret)
			return ret;
		break;
	}
	case RDMA_CQ_SETUP:{
		struct rdma_cq_setup *rdma = data;

		spin_lock_irq(&adapter->sge.reg_lock);
		ret =
			t3_sge_init_cqcntxt(adapter, rdma->id,
					rdma->base_addr, rdma->size,
					ASYNC_NOTIF_RSPQ,
					rdma->ovfl_mode, rdma->credits,
					rdma->credit_thres);
		spin_unlock_irq(&adapter->sge.reg_lock);
		break;
	}
	case RDMA_CQ_DISABLE:
		spin_lock_irq(&adapter->sge.reg_lock);
		ret = t3_sge_disable_cqcntxt(adapter, *(unsigned int *)data);
		spin_unlock_irq(&adapter->sge.reg_lock);
		break;
	case RDMA_CTRL_QP_SETUP:{
		struct rdma_ctrlqp_setup *rdma = data;

		spin_lock_irq(&adapter->sge.reg_lock);
		ret = t3_sge_init_ecntxt(adapter, FW_RI_SGEEC_START, 0,
						SGE_CNTXT_RDMA,
						ASYNC_NOTIF_RSPQ,
						rdma->base_addr, rdma->size,
						FW_RI_TID_START, 1, 0);
		spin_unlock_irq(&adapter->sge.reg_lock);
		break;
	}
	default:
		ret = -EOPNOTSUPP;
	}
	return ret;
}

static int cxgb_offload_ctl(struct t3cdev *tdev, unsigned int req, void *data)
{
	struct adapter *adapter = tdev2adap(tdev);
	struct tid_range *tid;
	struct mtutab *mtup;
	struct iff_mac *iffmacp;
	struct ddp_params *ddpp;
	struct adap_ports *ports;
	struct ofld_page_info *rx_page_info;
	struct tp_params *tp = &adapter->params.tp;
	int i;

	switch (req) {
	case GET_MAX_OUTSTANDING_WR:
		*(unsigned int *)data = FW_WR_NUM;
		break;
	case GET_WR_LEN:
		*(unsigned int *)data = WR_FLITS;
		break;
	case GET_TX_MAX_CHUNK:
		*(unsigned int *)data = 1 << 20;	/* 1MB */
		break;
	case GET_TID_RANGE:
		tid = data;
		tid->num = t3_mc5_size(&adapter->mc5) -
		    adapter->params.mc5.nroutes -
		    adapter->params.mc5.nfilters - adapter->params.mc5.nservers;
		tid->base = 0;
		break;
	case GET_STID_RANGE:
		tid = data;
		tid->num = adapter->params.mc5.nservers;
		tid->base = t3_mc5_size(&adapter->mc5) - tid->num -
		    adapter->params.mc5.nfilters - adapter->params.mc5.nroutes;
		break;
	case GET_L2T_CAPACITY:
		*(unsigned int *)data = 2048;
		break;
	case GET_MTUS:
		mtup = data;
		mtup->size = NMTUS;
		mtup->mtus = adapter->params.mtus;
		break;
	case GET_IFF_FROM_MAC:
		iffmacp = data;
		iffmacp->dev = get_iff_from_mac(adapter, iffmacp->mac_addr,
						iffmacp->vlan_tag &
						VLAN_VID_MASK);
		break;
	case GET_DDP_PARAMS:
		ddpp = data;
		ddpp->llimit = t3_read_reg(adapter, A_ULPRX_TDDP_LLIMIT);
		ddpp->ulimit = t3_read_reg(adapter, A_ULPRX_TDDP_ULIMIT);
		ddpp->tag_mask = t3_read_reg(adapter, A_ULPRX_TDDP_TAGMASK);
		break;
	case GET_PORTS:
		ports = data;
		ports->nports = adapter->params.nports;
		for_each_port(adapter, i)
			ports->lldevs[i] = adapter->port[i];
		break;
	case ULP_ISCSI_GET_PARAMS:
	case ULP_ISCSI_SET_PARAMS:
		if (!offload_running(adapter))
			return -EAGAIN;
		return cxgb_ulp_iscsi_ctl(adapter, req, data);
	case RDMA_GET_PARAMS:
	case RDMA_CQ_OP:
	case RDMA_CQ_SETUP:
	case RDMA_CQ_DISABLE:
	case RDMA_CTRL_QP_SETUP:
	case RDMA_GET_MEM:
		if (!offload_running(adapter))
			return -EAGAIN;
		return cxgb_rdma_ctl(adapter, req, data);
	case GET_RX_PAGE_INFO:
		rx_page_info = data;
		rx_page_info->page_size = tp->rx_pg_size;
		rx_page_info->num = tp->rx_num_pgs;
		break;
	default:
		return -EOPNOTSUPP;
	}
	return 0;
}

/*
 * Dummy handler for Rx offload packets in case we get an offload packet before
 * proper processing is setup.  This complains and drops the packet as it isn't
 * normal to get offload packets at this stage.
 */
static int rx_offload_blackhole(struct t3cdev *dev, struct sk_buff **skbs,
				int n)
{
	while (n--)
		dev_kfree_skb_any(skbs[n]);
	return 0;
}

static void dummy_neigh_update(struct t3cdev *dev, struct neighbour *neigh)
{
}

void cxgb3_set_dummy_ops(struct t3cdev *dev)
{
	dev->recv = rx_offload_blackhole;
	dev->neigh_update = dummy_neigh_update;
}

/*
 * Free an active-open TID.
 */
void *cxgb3_free_atid(struct t3cdev *tdev, int atid)
{
	struct tid_info *t = &(T3C_DATA(tdev))->tid_maps;
	union active_open_entry *p = atid2entry(t, atid);
	void *ctx = p->t3c_tid.ctx;

	spin_lock_bh(&t->atid_lock);
	p->next = t->afree;
	t->afree = p;
	t->atids_in_use--;
	spin_unlock_bh(&t->atid_lock);

	return ctx;
}

EXPORT_SYMBOL(cxgb3_free_atid);

/*
 * Free a server TID and return it to the free pool.
 */
void cxgb3_free_stid(struct t3cdev *tdev, int stid)
{
	struct tid_info *t = &(T3C_DATA(tdev))->tid_maps;
	union listen_entry *p = stid2entry(t, stid);

	spin_lock_bh(&t->stid_lock);
	p->next = t->sfree;
	t->sfree = p;
	t->stids_in_use--;
	spin_unlock_bh(&t->stid_lock);
}

EXPORT_SYMBOL(cxgb3_free_stid);

void cxgb3_insert_tid(struct t3cdev *tdev, struct cxgb3_client *client,
		      void *ctx, unsigned int tid)
{
	struct tid_info *t = &(T3C_DATA(tdev))->tid_maps;

	t->tid_tab[tid].client = client;
	t->tid_tab[tid].ctx = ctx;
	atomic_inc(&t->tids_in_use);
}

EXPORT_SYMBOL(cxgb3_insert_tid);

/*
 * Populate a TID_RELEASE WR.  The skb must be already propely sized.
 */
static inline void mk_tid_release(struct sk_buff *skb, unsigned int tid)
{
	struct cpl_tid_release *req;

	skb->priority = CPL_PRIORITY_SETUP;
	req = (struct cpl_tid_release *)__skb_put(skb, sizeof(*req));
	req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_TID_RELEASE, tid));
}

static void t3_process_tid_release_list(struct work_struct *work)
{
	struct t3c_data *td = container_of(work, struct t3c_data,
					   tid_release_task);
	struct sk_buff *skb;
	struct t3cdev *tdev = td->dev;


	spin_lock_bh(&td->tid_release_lock);
	while (td->tid_release_list) {
		struct t3c_tid_entry *p = td->tid_release_list;

		td->tid_release_list = (struct t3c_tid_entry *)p->ctx;
		spin_unlock_bh(&td->tid_release_lock);

		skb = alloc_skb(sizeof(struct cpl_tid_release),
				GFP_KERNEL | __GFP_NOFAIL);
		mk_tid_release(skb, p - td->tid_maps.tid_tab);
		cxgb3_ofld_send(tdev, skb);
		p->ctx = NULL;
		spin_lock_bh(&td->tid_release_lock);
	}
	spin_unlock_bh(&td->tid_release_lock);
}

/* use ctx as a next pointer in the tid release list */
void cxgb3_queue_tid_release(struct t3cdev *tdev, unsigned int tid)
{
	struct t3c_data *td = T3C_DATA(tdev);
	struct t3c_tid_entry *p = &td->tid_maps.tid_tab[tid];

	spin_lock_bh(&td->tid_release_lock);
	p->ctx = (void *)td->tid_release_list;
	p->client = NULL;
	td->tid_release_list = p;
	if (!p->ctx)
		schedule_work(&td->tid_release_task);
	spin_unlock_bh(&td->tid_release_lock);
}

EXPORT_SYMBOL(cxgb3_queue_tid_release);

/*
 * Remove a tid from the TID table.  A client may defer processing its last
 * CPL message if it is locked at the time it arrives, and while the message
 * sits in the client's backlog the TID may be reused for another connection.
 * To handle this we atomically switch the TID association if it still points
 * to the original client context.
 */
void cxgb3_remove_tid(struct t3cdev *tdev, void *ctx, unsigned int tid)
{
	struct tid_info *t = &(T3C_DATA(tdev))->tid_maps;

	BUG_ON(tid >= t->ntids);
	if (tdev->type == T3A)
		(void)cmpxchg(&t->tid_tab[tid].ctx, ctx, NULL);
	else {
		struct sk_buff *skb;

		skb = alloc_skb(sizeof(struct cpl_tid_release), GFP_ATOMIC);
		if (likely(skb)) {
			mk_tid_release(skb, tid);
			cxgb3_ofld_send(tdev, skb);
			t->tid_tab[tid].ctx = NULL;
		} else
			cxgb3_queue_tid_release(tdev, tid);
	}
	atomic_dec(&t->tids_in_use);
}

EXPORT_SYMBOL(cxgb3_remove_tid);

int cxgb3_alloc_atid(struct t3cdev *tdev, struct cxgb3_client *client,
		     void *ctx)
{
	int atid = -1;
	struct tid_info *t = &(T3C_DATA(tdev))->tid_maps;

	spin_lock_bh(&t->atid_lock);
	if (t->afree &&
	    t->atids_in_use + atomic_read(&t->tids_in_use) + MC5_MIN_TIDS <=
	    t->ntids) {
		union active_open_entry *p = t->afree;

		atid = (p - t->atid_tab) + t->atid_base;
		t->afree = p->next;
		p->t3c_tid.ctx = ctx;
		p->t3c_tid.client = client;
		t->atids_in_use++;
	}
	spin_unlock_bh(&t->atid_lock);
	return atid;
}

EXPORT_SYMBOL(cxgb3_alloc_atid);

int cxgb3_alloc_stid(struct t3cdev *tdev, struct cxgb3_client *client,
		     void *ctx)
{
	int stid = -1;
	struct tid_info *t = &(T3C_DATA(tdev))->tid_maps;

	spin_lock_bh(&t->stid_lock);
	if (t->sfree) {
		union listen_entry *p = t->sfree;

		stid = (p - t->stid_tab) + t->stid_base;
		t->sfree = p->next;
		p->t3c_tid.ctx = ctx;
		p->t3c_tid.client = client;
		t->stids_in_use++;
	}
	spin_unlock_bh(&t->stid_lock);
	return stid;
}

EXPORT_SYMBOL(cxgb3_alloc_stid);

/* Get the t3cdev associated with a net_device */
struct t3cdev *dev2t3cdev(struct net_device *dev)
{
	const struct port_info *pi = netdev_priv(dev);

	return (struct t3cdev *)pi->adapter;
}

EXPORT_SYMBOL(dev2t3cdev);

static int do_smt_write_rpl(struct t3cdev *dev, struct sk_buff *skb)
{
	struct cpl_smt_write_rpl *rpl = cplhdr(skb);

	if (rpl->status != CPL_ERR_NONE)
		printk(KERN_ERR
		       "Unexpected SMT_WRITE_RPL status %u for entry %u\n",
		       rpl->status, GET_TID(rpl));

	return CPL_RET_BUF_DONE;
}

static int do_l2t_write_rpl(struct t3cdev *dev, struct sk_buff *skb)
{
	struct cpl_l2t_write_rpl *rpl = cplhdr(skb);

	if (rpl->status != CPL_ERR_NONE)
		printk(KERN_ERR
		       "Unexpected L2T_WRITE_RPL status %u for entry %u\n",
		       rpl->status, GET_TID(rpl));

	return CPL_RET_BUF_DONE;
}

static int do_rte_write_rpl(struct t3cdev *dev, struct sk_buff *skb)
{
	struct cpl_rte_write_rpl *rpl = cplhdr(skb);

	if (rpl->status != CPL_ERR_NONE)
		printk(KERN_ERR
		       "Unexpected RTE_WRITE_RPL status %u for entry %u\n",
		       rpl->status, GET_TID(rpl));

	return CPL_RET_BUF_DONE;
}

static int do_act_open_rpl(struct t3cdev *dev, struct sk_buff *skb)
{
	struct cpl_act_open_rpl *rpl = cplhdr(skb);
	unsigned int atid = G_TID(ntohl(rpl->atid));
	struct t3c_tid_entry *t3c_tid;

	t3c_tid = lookup_atid(&(T3C_DATA(dev))->tid_maps, atid);
	if (t3c_tid && t3c_tid->ctx && t3c_tid->client &&
	    t3c_tid->client->handlers &&
	    t3c_tid->client->handlers[CPL_ACT_OPEN_RPL]) {
		return t3c_tid->client->handlers[CPL_ACT_OPEN_RPL] (dev, skb,
								    t3c_tid->
								    ctx);
	} else {
		printk(KERN_ERR "%s: received clientless CPL command 0x%x\n",
		       dev->name, CPL_ACT_OPEN_RPL);
		return CPL_RET_BUF_DONE | CPL_RET_BAD_MSG;
	}
}

static int do_stid_rpl(struct t3cdev *dev, struct sk_buff *skb)
{
	union opcode_tid *p = cplhdr(skb);
	unsigned int stid = G_TID(ntohl(p->opcode_tid));
	struct t3c_tid_entry *t3c_tid;

	t3c_tid = lookup_stid(&(T3C_DATA(dev))->tid_maps, stid);
	if (t3c_tid && t3c_tid->ctx && t3c_tid->client->handlers &&
	    t3c_tid->client->handlers[p->opcode]) {
		return t3c_tid->client->handlers[p->opcode] (dev, skb,
							     t3c_tid->ctx);
	} else {
		printk(KERN_ERR "%s: received clientless CPL command 0x%x\n",
		       dev->name, p->opcode);
		return CPL_RET_BUF_DONE | CPL_RET_BAD_MSG;
	}
}

static int do_hwtid_rpl(struct t3cdev *dev, struct sk_buff *skb)
{
	union opcode_tid *p = cplhdr(skb);
	unsigned int hwtid = G_TID(ntohl(p->opcode_tid));
	struct t3c_tid_entry *t3c_tid;

	t3c_tid = lookup_tid(&(T3C_DATA(dev))->tid_maps, hwtid);
	if (t3c_tid && t3c_tid->ctx && t3c_tid->client->handlers &&
	    t3c_tid->client->handlers[p->opcode]) {
		return t3c_tid->client->handlers[p->opcode]
		    (dev, skb, t3c_tid->ctx);
	} else {
		printk(KERN_ERR "%s: received clientless CPL command 0x%x\n",
		       dev->name, p->opcode);
		return CPL_RET_BUF_DONE | CPL_RET_BAD_MSG;
	}
}

static int do_cr(struct t3cdev *dev, struct sk_buff *skb)
{
	struct cpl_pass_accept_req *req = cplhdr(skb);
	unsigned int stid = G_PASS_OPEN_TID(ntohl(req->tos_tid));
	struct tid_info *t = &(T3C_DATA(dev))->tid_maps;
	struct t3c_tid_entry *t3c_tid;
	unsigned int tid = GET_TID(req);

	if (unlikely(tid >= t->ntids)) {
		printk("%s: passive open TID %u too large\n",
		       dev->name, tid);
		t3_fatal_err(tdev2adap(dev));
		return CPL_RET_BUF_DONE;
	}

	t3c_tid = lookup_stid(t, stid);
	if (t3c_tid && t3c_tid->ctx && t3c_tid->client->handlers &&
	    t3c_tid->client->handlers[CPL_PASS_ACCEPT_REQ]) {
		return t3c_tid->client->handlers[CPL_PASS_ACCEPT_REQ]
		    (dev, skb, t3c_tid->ctx);
	} else {
		printk(KERN_ERR "%s: received clientless CPL command 0x%x\n",
		       dev->name, CPL_PASS_ACCEPT_REQ);
		return CPL_RET_BUF_DONE | CPL_RET_BAD_MSG;
	}
}

/*
 * Returns an sk_buff for a reply CPL message of size len.  If the input
 * sk_buff has no other users it is trimmed and reused, otherwise a new buffer
 * is allocated.  The input skb must be of size at least len.  Note that this
 * operation does not destroy the original skb data even if it decides to reuse
 * the buffer.
 */
static struct sk_buff *cxgb3_get_cpl_reply_skb(struct sk_buff *skb, size_t len,
					       gfp_t gfp)
{
	if (likely(!skb_cloned(skb))) {
		BUG_ON(skb->len < len);
		__skb_trim(skb, len);
		skb_get(skb);
	} else {
		skb = alloc_skb(len, gfp);
		if (skb)
			__skb_put(skb, len);
	}
	return skb;
}

static int do_abort_req_rss(struct t3cdev *dev, struct sk_buff *skb)
{
	union opcode_tid *p = cplhdr(skb);
	unsigned int hwtid = G_TID(ntohl(p->opcode_tid));
	struct t3c_tid_entry *t3c_tid;

	t3c_tid = lookup_tid(&(T3C_DATA(dev))->tid_maps, hwtid);
	if (t3c_tid && t3c_tid->ctx && t3c_tid->client->handlers &&
	    t3c_tid->client->handlers[p->opcode]) {
		return t3c_tid->client->handlers[p->opcode]
		    (dev, skb, t3c_tid->ctx);
	} else {
		struct cpl_abort_req_rss *req = cplhdr(skb);
		struct cpl_abort_rpl *rpl;
		struct sk_buff *reply_skb;
		unsigned int tid = GET_TID(req);
		u8 cmd = req->status;

		if (req->status == CPL_ERR_RTX_NEG_ADVICE ||
		    req->status == CPL_ERR_PERSIST_NEG_ADVICE)
			goto out;

		reply_skb = cxgb3_get_cpl_reply_skb(skb,
						    sizeof(struct
							   cpl_abort_rpl),
						    GFP_ATOMIC);

		if (!reply_skb) {
			printk("do_abort_req_rss: couldn't get skb!\n");
			goto out;
		}
		reply_skb->priority = CPL_PRIORITY_DATA;
		__skb_put(reply_skb, sizeof(struct cpl_abort_rpl));
		rpl = cplhdr(reply_skb);
		rpl->wr.wr_hi =
		    htonl(V_WR_OP(FW_WROPCODE_OFLD_HOST_ABORT_CON_RPL));
		rpl->wr.wr_lo = htonl(V_WR_TID(tid));
		OPCODE_TID(rpl) = htonl(MK_OPCODE_TID(CPL_ABORT_RPL, tid));
		rpl->cmd = cmd;
		cxgb3_ofld_send(dev, reply_skb);
out:
		return CPL_RET_BUF_DONE;
	}
}

static int do_act_establish(struct t3cdev *dev, struct sk_buff *skb)
{
	struct cpl_act_establish *req = cplhdr(skb);
	unsigned int atid = G_PASS_OPEN_TID(ntohl(req->tos_tid));
	struct tid_info *t = &(T3C_DATA(dev))->tid_maps;
	struct t3c_tid_entry *t3c_tid;
	unsigned int tid = GET_TID(req);

	if (unlikely(tid >= t->ntids)) {
		printk("%s: active establish TID %u too large\n",
		       dev->name, tid);
		t3_fatal_err(tdev2adap(dev));
		return CPL_RET_BUF_DONE;
	}

	t3c_tid = lookup_atid(t, atid);
	if (t3c_tid && t3c_tid->ctx && t3c_tid->client->handlers &&
	    t3c_tid->client->handlers[CPL_ACT_ESTABLISH]) {
		return t3c_tid->client->handlers[CPL_ACT_ESTABLISH]
		    (dev, skb, t3c_tid->ctx);
	} else {
		printk(KERN_ERR "%s: received clientless CPL command 0x%x\n",
		       dev->name, CPL_ACT_ESTABLISH);
		return CPL_RET_BUF_DONE | CPL_RET_BAD_MSG;
	}
}

static int do_trace(struct t3cdev *dev, struct sk_buff *skb)
{
	struct cpl_trace_pkt *p = cplhdr(skb);

	skb->protocol = htons(0xffff);
	skb->dev = dev->lldev;
	skb_pull(skb, sizeof(*p));
	skb_reset_mac_header(skb);
	netif_receive_skb(skb);
	return 0;
}

/*
 * That skb would better have come from process_responses() where we abuse
 * ->priority and ->csum to carry our data.  NB: if we get to per-arch
 * ->csum, the things might get really interesting here.
 */

static inline u32 get_hwtid(struct sk_buff *skb)
{
	return ntohl((__force __be32)skb->priority) >> 8 & 0xfffff;
}

static inline u32 get_opcode(struct sk_buff *skb)
{
	return G_OPCODE(ntohl((__force __be32)skb->csum));
}

static int do_term(struct t3cdev *dev, struct sk_buff *skb)
{
	unsigned int hwtid = get_hwtid(skb);
	unsigned int opcode = get_opcode(skb);
	struct t3c_tid_entry *t3c_tid;

	t3c_tid = lookup_tid(&(T3C_DATA(dev))->tid_maps, hwtid);
	if (t3c_tid && t3c_tid->ctx && t3c_tid->client->handlers &&
	    t3c_tid->client->handlers[opcode]) {
		return t3c_tid->client->handlers[opcode] (dev, skb,
							  t3c_tid->ctx);
	} else {
		printk(KERN_ERR "%s: received clientless CPL command 0x%x\n",
		       dev->name, opcode);
		return CPL_RET_BUF_DONE | CPL_RET_BAD_MSG;
	}
}

static int nb_callback(struct notifier_block *self, unsigned long event,
		       void *ctx)
{
	switch (event) {
	case (NETEVENT_NEIGH_UPDATE):{
		cxgb_neigh_update((struct neighbour *)ctx);
		break;
	}
	case (NETEVENT_PMTU_UPDATE):
		break;
	case (NETEVENT_REDIRECT):{
		struct netevent_redirect *nr = ctx;
		cxgb_redirect(nr->old, nr->new);
		cxgb_neigh_update(nr->new->neighbour);
		break;
	}
	default:
		break;
	}
	return 0;
}

static struct notifier_block nb = {
	.notifier_call = nb_callback
};

/*
 * Process a received packet with an unknown/unexpected CPL opcode.
 */
static int do_bad_cpl(struct t3cdev *dev, struct sk_buff *skb)
{
	printk(KERN_ERR "%s: received bad CPL command 0x%x\n", dev->name,
	       *skb->data);
	return CPL_RET_BUF_DONE | CPL_RET_BAD_MSG;
}

/*
 * Handlers for each CPL opcode
 */
static cpl_handler_func cpl_handlers[NUM_CPL_CMDS];

/*
 * Add a new handler to the CPL dispatch table.  A NULL handler may be supplied
 * to unregister an existing handler.
 */
void t3_register_cpl_handler(unsigned int opcode, cpl_handler_func h)
{
	if (opcode < NUM_CPL_CMDS)
		cpl_handlers[opcode] = h ? h : do_bad_cpl;
	else
		printk(KERN_ERR "T3C: handler registration for "
		       "opcode %x failed\n", opcode);
}

EXPORT_SYMBOL(t3_register_cpl_handler);

/*
 * T3CDEV's receive method.
 */
int process_rx(struct t3cdev *dev, struct sk_buff **skbs, int n)
{
	while (n--) {
		struct sk_buff *skb = *skbs++;
		unsigned int opcode = get_opcode(skb);
		int ret = cpl_handlers[opcode] (dev, skb);

#if VALIDATE_TID
		if (ret & CPL_RET_UNKNOWN_TID) {
			union opcode_tid *p = cplhdr(skb);

			printk(KERN_ERR "%s: CPL message (opcode %u) had "
			       "unknown TID %u\n", dev->name, opcode,
			       G_TID(ntohl(p->opcode_tid)));
		}
#endif
		if (ret & CPL_RET_BUF_DONE)
			kfree_skb(skb);
	}
	return 0;
}

/*
 * Sends an sk_buff to a T3C driver after dealing with any active network taps.
 */
int cxgb3_ofld_send(struct t3cdev *dev, struct sk_buff *skb)
{
	int r;

	local_bh_disable();
	r = dev->send(dev, skb);
	local_bh_enable();
	return r;
}

EXPORT_SYMBOL(cxgb3_ofld_send);

static int is_offloading(struct net_device *dev)
{
	struct adapter *adapter;
	int i;

	read_lock_bh(&adapter_list_lock);
	list_for_each_entry(adapter, &adapter_list, adapter_list) {
		for_each_port(adapter, i) {
			if (dev == adapter->port[i]) {
				read_unlock_bh(&adapter_list_lock);
				return 1;
			}
		}
	}
	read_unlock_bh(&adapter_list_lock);
	return 0;
}

void cxgb_neigh_update(struct neighbour *neigh)
{
	struct net_device *dev = neigh->dev;

	if (dev && (is_offloading(dev))) {
		struct t3cdev *tdev = dev2t3cdev(dev);

		BUG_ON(!tdev);
		t3_l2t_update(tdev, neigh);
	}
}

static void set_l2t_ix(struct t3cdev *tdev, u32 tid, struct l2t_entry *e)
{
	struct sk_buff *skb;
	struct cpl_set_tcb_field *req;

	skb = alloc_skb(sizeof(*req), GFP_ATOMIC);
	if (!skb) {
		printk(KERN_ERR "%s: cannot allocate skb!\n", __FUNCTION__);
		return;
	}
	skb->priority = CPL_PRIORITY_CONTROL;
	req = (struct cpl_set_tcb_field *)skb_put(skb, sizeof(*req));
	req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_SET_TCB_FIELD, tid));
	req->reply = 0;
	req->cpu_idx = 0;
	req->word = htons(W_TCB_L2T_IX);
	req->mask = cpu_to_be64(V_TCB_L2T_IX(M_TCB_L2T_IX));
	req->val = cpu_to_be64(V_TCB_L2T_IX(e->idx));
	tdev->send(tdev, skb);
}

void cxgb_redirect(struct dst_entry *old, struct dst_entry *new)
{
	struct net_device *olddev, *newdev;
	struct tid_info *ti;
	struct t3cdev *tdev;
	u32 tid;
	int update_tcb;
	struct l2t_entry *e;
	struct t3c_tid_entry *te;

	olddev = old->neighbour->dev;
	newdev = new->neighbour->dev;
	if (!is_offloading(olddev))
		return;
	if (!is_offloading(newdev)) {
		printk(KERN_WARNING "%s: Redirect to non-offload "
		       "device ignored.\n", __FUNCTION__);
		return;
	}
	tdev = dev2t3cdev(olddev);
	BUG_ON(!tdev);
	if (tdev != dev2t3cdev(newdev)) {
		printk(KERN_WARNING "%s: Redirect to different "
		       "offload device ignored.\n", __FUNCTION__);
		return;
	}

	/* Add new L2T entry */
	e = t3_l2t_get(tdev, new->neighbour, newdev);
	if (!e) {
		printk(KERN_ERR "%s: couldn't allocate new l2t entry!\n",
		       __FUNCTION__);
		return;
	}

	/* Walk tid table and notify clients of dst change. */
	ti = &(T3C_DATA(tdev))->tid_maps;
	for (tid = 0; tid < ti->ntids; tid++) {
		te = lookup_tid(ti, tid);
		BUG_ON(!te);
		if (te && te->ctx && te->client && te->client->redirect) {
			update_tcb = te->client->redirect(te->ctx, old, new, e);
			if (update_tcb) {
				l2t_hold(L2DATA(tdev), e);
				set_l2t_ix(tdev, tid, e);
			}
		}
	}
	l2t_release(L2DATA(tdev), e);
}

/*
 * Allocate a chunk of memory using kmalloc or, if that fails, vmalloc.
 * The allocated memory is cleared.
 */
void *cxgb_alloc_mem(unsigned long size)
{
	void *p = kmalloc(size, GFP_KERNEL);

	if (!p)
		p = vmalloc(size);
	if (p)
		memset(p, 0, size);
	return p;
}

/*
 * Free memory allocated through t3_alloc_mem().
 */
void cxgb_free_mem(void *addr)
{
	if (is_vmalloc_addr(addr))
		vfree(addr);
	else
		kfree(addr);
}

/*
 * Allocate and initialize the TID tables.  Returns 0 on success.
 */
static int init_tid_tabs(struct tid_info *t, unsigned int ntids,
			 unsigned int natids, unsigned int nstids,
			 unsigned int atid_base, unsigned int stid_base)
{
	unsigned long size = ntids * sizeof(*t->tid_tab) +
	    natids * sizeof(*t->atid_tab) + nstids * sizeof(*t->stid_tab);

	t->tid_tab = cxgb_alloc_mem(size);
	if (!t->tid_tab)
		return -ENOMEM;

	t->stid_tab = (union listen_entry *)&t->tid_tab[ntids];
	t->atid_tab = (union active_open_entry *)&t->stid_tab[nstids];
	t->ntids = ntids;
	t->nstids = nstids;
	t->stid_base = stid_base;
	t->sfree = NULL;
	t->natids = natids;
	t->atid_base = atid_base;
	t->afree = NULL;
	t->stids_in_use = t->atids_in_use = 0;
	atomic_set(&t->tids_in_use, 0);
	spin_lock_init(&t->stid_lock);
	spin_lock_init(&t->atid_lock);

	/*
	 * Setup the free lists for stid_tab and atid_tab.
	 */
	if (nstids) {
		while (--nstids)
			t->stid_tab[nstids - 1].next = &t->stid_tab[nstids];
		t->sfree = t->stid_tab;
	}
	if (natids) {
		while (--natids)
			t->atid_tab[natids - 1].next = &t->atid_tab[natids];
		t->afree = t->atid_tab;
	}
	return 0;
}

static void free_tid_maps(struct tid_info *t)
{
	cxgb_free_mem(t->tid_tab);
}

static inline void add_adapter(struct adapter *adap)
{
	write_lock_bh(&adapter_list_lock);
	list_add_tail(&adap->adapter_list, &adapter_list);
	write_unlock_bh(&adapter_list_lock);
}

static inline void remove_adapter(struct adapter *adap)
{
	write_lock_bh(&adapter_list_lock);
	list_del(&adap->adapter_list);
	write_unlock_bh(&adapter_list_lock);
}

int cxgb3_offload_activate(struct adapter *adapter)
{
	struct t3cdev *dev = &adapter->tdev;
	int natids, err;
	struct t3c_data *t;
	struct tid_range stid_range, tid_range;
	struct mtutab mtutab;
	unsigned int l2t_capacity;

	t = kcalloc(1, sizeof(*t), GFP_KERNEL);
	if (!t)
		return -ENOMEM;

	err = -EOPNOTSUPP;
	if (dev->ctl(dev, GET_TX_MAX_CHUNK, &t->tx_max_chunk) < 0 ||
	    dev->ctl(dev, GET_MAX_OUTSTANDING_WR, &t->max_wrs) < 0 ||
	    dev->ctl(dev, GET_L2T_CAPACITY, &l2t_capacity) < 0 ||
	    dev->ctl(dev, GET_MTUS, &mtutab) < 0 ||
	    dev->ctl(dev, GET_TID_RANGE, &tid_range) < 0 ||
	    dev->ctl(dev, GET_STID_RANGE, &stid_range) < 0)
		goto out_free;

	err = -ENOMEM;
	L2DATA(dev) = t3_init_l2t(l2t_capacity);
	if (!L2DATA(dev))
		goto out_free;

	natids = min(tid_range.num / 2, MAX_ATIDS);
	err = init_tid_tabs(&t->tid_maps, tid_range.num, natids,
			    stid_range.num, ATID_BASE, stid_range.base);
	if (err)
		goto out_free_l2t;

	t->mtus = mtutab.mtus;
	t->nmtus = mtutab.size;

	INIT_WORK(&t->tid_release_task, t3_process_tid_release_list);
	spin_lock_init(&t->tid_release_lock);
	INIT_LIST_HEAD(&t->list_node);
	t->dev = dev;

	T3C_DATA(dev) = t;
	dev->recv = process_rx;
	dev->neigh_update = t3_l2t_update;

	/* Register netevent handler once */
	if (list_empty(&adapter_list))
		register_netevent_notifier(&nb);

	add_adapter(adapter);
	return 0;

out_free_l2t:
	t3_free_l2t(L2DATA(dev));
	L2DATA(dev) = NULL;
out_free:
	kfree(t);
	return err;
}

void cxgb3_offload_deactivate(struct adapter *adapter)
{
	struct t3cdev *tdev = &adapter->tdev;
	struct t3c_data *t = T3C_DATA(tdev);

	remove_adapter(adapter);
	if (list_empty(&adapter_list))
		unregister_netevent_notifier(&nb);

	free_tid_maps(&t->tid_maps);
	T3C_DATA(tdev) = NULL;
	t3_free_l2t(L2DATA(tdev));
	L2DATA(tdev) = NULL;
	kfree(t);
}

static inline void register_tdev(struct t3cdev *tdev)
{
	static int unit;

	mutex_lock(&cxgb3_db_lock);
	snprintf(tdev->name, sizeof(tdev->name), "ofld_dev%d", unit++);
	list_add_tail(&tdev->ofld_dev_list, &ofld_dev_list);
	mutex_unlock(&cxgb3_db_lock);
}

static inline void unregister_tdev(struct t3cdev *tdev)
{
	mutex_lock(&cxgb3_db_lock);
	list_del(&tdev->ofld_dev_list);
	mutex_unlock(&cxgb3_db_lock);
}

void __devinit cxgb3_adapter_ofld(struct adapter *adapter)
{
	struct t3cdev *tdev = &adapter->tdev;

	INIT_LIST_HEAD(&tdev->ofld_dev_list);

	cxgb3_set_dummy_ops(tdev);
	tdev->send = t3_offload_tx;
	tdev->ctl = cxgb_offload_ctl;
	tdev->type = adapter->params.rev == 0 ? T3A : T3B;

	register_tdev(tdev);
}

void __devexit cxgb3_adapter_unofld(struct adapter *adapter)
{
	struct t3cdev *tdev = &adapter->tdev;

	tdev->recv = NULL;
	tdev->neigh_update = NULL;

	unregister_tdev(tdev);
}

void __init cxgb3_offload_init(void)
{
	int i;

	for (i = 0; i < NUM_CPL_CMDS; ++i)
		cpl_handlers[i] = do_bad_cpl;

	t3_register_cpl_handler(CPL_SMT_WRITE_RPL, do_smt_write_rpl);
	t3_register_cpl_handler(CPL_L2T_WRITE_RPL, do_l2t_write_rpl);
	t3_register_cpl_handler(CPL_RTE_WRITE_RPL, do_rte_write_rpl);
	t3_register_cpl_handler(CPL_PASS_OPEN_RPL, do_stid_rpl);
	t3_register_cpl_handler(CPL_CLOSE_LISTSRV_RPL, do_stid_rpl);
	t3_register_cpl_handler(CPL_PASS_ACCEPT_REQ, do_cr);
	t3_register_cpl_handler(CPL_PASS_ESTABLISH, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_ABORT_RPL_RSS, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_ABORT_RPL, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_RX_URG_NOTIFY, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_RX_DATA, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_TX_DATA_ACK, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_TX_DMA_ACK, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_ACT_OPEN_RPL, do_act_open_rpl);
	t3_register_cpl_handler(CPL_PEER_CLOSE, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_CLOSE_CON_RPL, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_ABORT_REQ_RSS, do_abort_req_rss);
	t3_register_cpl_handler(CPL_ACT_ESTABLISH, do_act_establish);
	t3_register_cpl_handler(CPL_SET_TCB_RPL, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_GET_TCB_RPL, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_RDMA_TERMINATE, do_term);
	t3_register_cpl_handler(CPL_RDMA_EC_STATUS, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_TRACE_PKT, do_trace);
	t3_register_cpl_handler(CPL_RX_DATA_DDP, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_RX_DDP_COMPLETE, do_hwtid_rpl);
	t3_register_cpl_handler(CPL_ISCSI_HDR, do_hwtid_rpl);
}