is_vmalloc_addr(): Check if an address is within the vmalloc boundaries

[linux-2.6/cjktty.git] / 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;
}

static int do_term(struct t3cdev *dev, struct sk_buff *skb)
{
        unsigned int hwtid = ntohl(skb->priority) >> 8 & 0xfffff;
        unsigned int opcode = G_OPCODE(ntohl(skb->csum));
        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 = G_OPCODE(ntohl(skb->csum));
                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);
}