/*
 * cxgb3i_offload.c: Chelsio S3xx iscsi offloaded tcp connection management
 *
 * Copyright (C) 2003-2015 Chelsio Communications.  All rights reserved.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the LICENSE file included in this
 * release for licensing terms and conditions.
 *
 * Written by:  Dimitris Michailidis (dm@chelsio.com)
 *              Karen Xie (kxie@chelsio.com)
 */

#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <scsi/scsi_host.h>

#include "common.h"
#include "t3_cpl.h"
#include "t3cdev.h"
#include "cxgb3_defs.h"
#include "cxgb3_ctl_defs.h"
#include "cxgb3_offload.h"
#include "firmware_exports.h"
#include "cxgb3i.h"

static unsigned int dbg_level;
#include "../libcxgbi.h"

#define DRV_MODULE_NAME         "cxgb3i"
#define DRV_MODULE_DESC         "Chelsio T3 iSCSI Driver"
#define DRV_MODULE_VERSION      "2.0.1-ko"
#define DRV_MODULE_RELDATE      "Apr. 2015"

static char version[] =
        DRV_MODULE_DESC " " DRV_MODULE_NAME
        " v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";

MODULE_AUTHOR("Chelsio Communications, Inc.");
MODULE_DESCRIPTION(DRV_MODULE_DESC);
MODULE_VERSION(DRV_MODULE_VERSION);
MODULE_LICENSE("GPL");

module_param(dbg_level, uint, 0644);
MODULE_PARM_DESC(dbg_level, "debug flag (default=0)");

static int cxgb3i_rcv_win = 256 * 1024;
module_param(cxgb3i_rcv_win, int, 0644);
MODULE_PARM_DESC(cxgb3i_rcv_win, "TCP receive window in bytes (default=256KB)");

static int cxgb3i_snd_win = 128 * 1024;
module_param(cxgb3i_snd_win, int, 0644);
MODULE_PARM_DESC(cxgb3i_snd_win, "TCP send window in bytes (default=128KB)");

static int cxgb3i_rx_credit_thres = 10 * 1024;
module_param(cxgb3i_rx_credit_thres, int, 0644);
MODULE_PARM_DESC(cxgb3i_rx_credit_thres,
                 "RX credits return threshold in bytes (default=10KB)");

static unsigned int cxgb3i_max_connect = 8 * 1024;
module_param(cxgb3i_max_connect, uint, 0644);
MODULE_PARM_DESC(cxgb3i_max_connect, "Max. # of connections (default=8092)");

static unsigned int cxgb3i_sport_base = 20000;
module_param(cxgb3i_sport_base, uint, 0644);
MODULE_PARM_DESC(cxgb3i_sport_base, "starting port number (default=20000)");

static void cxgb3i_dev_open(struct t3cdev *);
static void cxgb3i_dev_close(struct t3cdev *);
static void cxgb3i_dev_event_handler(struct t3cdev *, u32, u32);

static struct cxgb3_client t3_client = {
        .name = DRV_MODULE_NAME,
        .handlers = cxgb3i_cpl_handlers,
        .add = cxgb3i_dev_open,
        .remove = cxgb3i_dev_close,
        .event_handler = cxgb3i_dev_event_handler,
};

static struct scsi_host_template cxgb3i_host_template = {
        .module         = THIS_MODULE,
        .name           = DRV_MODULE_NAME,
        .proc_name      = DRV_MODULE_NAME,
        .can_queue      = CXGB3I_SCSI_HOST_QDEPTH,
        .queuecommand   = iscsi_queuecommand,
        .change_queue_depth = scsi_change_queue_depth,
        .sg_tablesize   = SG_ALL,
        .max_sectors    = 0xFFFF,
        .cmd_per_lun    = ISCSI_DEF_CMD_PER_LUN,
        .eh_timed_out   = iscsi_eh_cmd_timed_out,
        .eh_abort_handler = iscsi_eh_abort,
        .eh_device_reset_handler = iscsi_eh_device_reset,
        .eh_target_reset_handler = iscsi_eh_recover_target,
        .target_alloc   = iscsi_target_alloc,
        .use_clustering = DISABLE_CLUSTERING,
        .this_id        = -1,
        .track_queue_depth = 1,
};

static struct iscsi_transport cxgb3i_iscsi_transport = {
        .owner          = THIS_MODULE,
        .name           = DRV_MODULE_NAME,
        /* owner and name should be set already */
        .caps           = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
                                | CAP_DATADGST | CAP_DIGEST_OFFLOAD |
                                CAP_PADDING_OFFLOAD | CAP_TEXT_NEGO,
        .attr_is_visible        = cxgbi_attr_is_visible,
        .get_host_param = cxgbi_get_host_param,
        .set_host_param = cxgbi_set_host_param,
        /* session management */
        .create_session = cxgbi_create_session,
        .destroy_session        = cxgbi_destroy_session,
        .get_session_param = iscsi_session_get_param,
        /* connection management */
        .create_conn    = cxgbi_create_conn,
        .bind_conn      = cxgbi_bind_conn,
        .destroy_conn   = iscsi_tcp_conn_teardown,
        .start_conn     = iscsi_conn_start,
        .stop_conn      = iscsi_conn_stop,
        .get_conn_param = iscsi_conn_get_param,
        .set_param      = cxgbi_set_conn_param,
        .get_stats      = cxgbi_get_conn_stats,
        /* pdu xmit req from user space */
        .send_pdu       = iscsi_conn_send_pdu,
        /* task */
        .init_task      = iscsi_tcp_task_init,
        .xmit_task      = iscsi_tcp_task_xmit,
        .cleanup_task   = cxgbi_cleanup_task,
        /* pdu */
        .alloc_pdu      = cxgbi_conn_alloc_pdu,
        .init_pdu       = cxgbi_conn_init_pdu,
        .xmit_pdu       = cxgbi_conn_xmit_pdu,
        .parse_pdu_itt  = cxgbi_parse_pdu_itt,
        /* TCP connect/disconnect */
        .get_ep_param   = cxgbi_get_ep_param,
        .ep_connect     = cxgbi_ep_connect,
        .ep_poll        = cxgbi_ep_poll,
        .ep_disconnect  = cxgbi_ep_disconnect,
        /* Error recovery timeout call */
        .session_recovery_timedout = iscsi_session_recovery_timedout,
};

static struct scsi_transport_template *cxgb3i_stt;

/*
 * CPL (Chelsio Protocol Language) defines a message passing interface between
 * the host driver and Chelsio asic.
 * The section below implments CPLs that related to iscsi tcp connection
 * open/close/abort and data send/receive.
 */

static int push_tx_frames(struct cxgbi_sock *csk, int req_completion);

static void send_act_open_req(struct cxgbi_sock *csk, struct sk_buff *skb,
                              const struct l2t_entry *e)
{
        unsigned int wscale = cxgbi_sock_compute_wscale(csk->rcv_win);
        struct cpl_act_open_req *req = (struct cpl_act_open_req *)skb->head;

        skb->priority = CPL_PRIORITY_SETUP;

        req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
        OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_ACT_OPEN_REQ, csk->atid));
        req->local_port = csk->saddr.sin_port;
        req->peer_port = csk->daddr.sin_port;
        req->local_ip = csk->saddr.sin_addr.s_addr;
        req->peer_ip = csk->daddr.sin_addr.s_addr;

        req->opt0h = htonl(V_KEEP_ALIVE(1) | F_TCAM_BYPASS |
                        V_WND_SCALE(wscale) | V_MSS_IDX(csk->mss_idx) |
                        V_L2T_IDX(e->idx) | V_TX_CHANNEL(e->smt_idx));
        req->opt0l = htonl(V_ULP_MODE(ULP2_MODE_ISCSI) |
                        V_RCV_BUFSIZ(csk->rcv_win >> 10));

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx,%u, %pI4:%u-%pI4:%u, %u,%u,%u.\n",
                csk, csk->state, csk->flags, csk->atid,
                &req->local_ip, ntohs(req->local_port),
                &req->peer_ip, ntohs(req->peer_port),
                csk->mss_idx, e->idx, e->smt_idx);

        l2t_send(csk->cdev->lldev, skb, csk->l2t);
}

static inline void act_open_arp_failure(struct t3cdev *dev, struct sk_buff *skb)
{
        cxgbi_sock_act_open_req_arp_failure(NULL, skb);
}

/*
 * CPL connection close request: host ->
 *
 * Close a connection by sending a CPL_CLOSE_CON_REQ message and queue it to
 * the write queue (i.e., after any unsent txt data).
 */
static void send_close_req(struct cxgbi_sock *csk)
{
        struct sk_buff *skb = csk->cpl_close;
        struct cpl_close_con_req *req = (struct cpl_close_con_req *)skb->head;
        unsigned int tid = csk->tid;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx,%u.\n",
                csk, csk->state, csk->flags, csk->tid);

        csk->cpl_close = NULL;
        req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_OFLD_CLOSE_CON));
        req->wr.wr_lo = htonl(V_WR_TID(tid));
        OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_CLOSE_CON_REQ, tid));
        req->rsvd = htonl(csk->write_seq);

        cxgbi_sock_skb_entail(csk, skb);
        if (csk->state >= CTP_ESTABLISHED)
                push_tx_frames(csk, 1);
}

/*
 * CPL connection abort request: host ->
 *
 * Send an ABORT_REQ message. Makes sure we do not send multiple ABORT_REQs
 * for the same connection and also that we do not try to send a message
 * after the connection has closed.
 */
static void abort_arp_failure(struct t3cdev *tdev, struct sk_buff *skb)
{
        struct cpl_abort_req *req = cplhdr(skb);

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "t3dev 0x%p, tid %u, skb 0x%p.\n",
                tdev, GET_TID(req), skb);
        req->cmd = CPL_ABORT_NO_RST;
        cxgb3_ofld_send(tdev, skb);
}

static void send_abort_req(struct cxgbi_sock *csk)
{
        struct sk_buff *skb = csk->cpl_abort_req;
        struct cpl_abort_req *req;

        if (unlikely(csk->state == CTP_ABORTING || !skb))
                return;
        cxgbi_sock_set_state(csk, CTP_ABORTING);
        cxgbi_sock_set_flag(csk, CTPF_ABORT_RPL_PENDING);
        /* Purge the send queue so we don't send anything after an abort. */
        cxgbi_sock_purge_write_queue(csk);

        csk->cpl_abort_req = NULL;
        req = (struct cpl_abort_req *)skb->head;
        skb->priority = CPL_PRIORITY_DATA;
        set_arp_failure_handler(skb, abort_arp_failure);
        req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_OFLD_HOST_ABORT_CON_REQ));
        req->wr.wr_lo = htonl(V_WR_TID(csk->tid));
        OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_ABORT_REQ, csk->tid));
        req->rsvd0 = htonl(csk->snd_nxt);
        req->rsvd1 = !cxgbi_sock_flag(csk, CTPF_TX_DATA_SENT);
        req->cmd = CPL_ABORT_SEND_RST;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx,%u, snd_nxt %u, 0x%x.\n",
                csk, csk->state, csk->flags, csk->tid, csk->snd_nxt,
                req->rsvd1);

        l2t_send(csk->cdev->lldev, skb, csk->l2t);
}

/*
 * CPL connection abort reply: host ->
 *
 * Send an ABORT_RPL message in response of the ABORT_REQ received.
 */
static void send_abort_rpl(struct cxgbi_sock *csk, int rst_status)
{
        struct sk_buff *skb = csk->cpl_abort_rpl;
        struct cpl_abort_rpl *rpl = (struct cpl_abort_rpl *)skb->head;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx,%u, status %d.\n",
                csk, csk->state, csk->flags, csk->tid, rst_status);

        csk->cpl_abort_rpl = NULL;
        skb->priority = CPL_PRIORITY_DATA;
        rpl->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_OFLD_HOST_ABORT_CON_RPL));
        rpl->wr.wr_lo = htonl(V_WR_TID(csk->tid));
        OPCODE_TID(rpl) = htonl(MK_OPCODE_TID(CPL_ABORT_RPL, csk->tid));
        rpl->cmd = rst_status;
        cxgb3_ofld_send(csk->cdev->lldev, skb);
}

/*
 * CPL connection rx data ack: host ->
 * Send RX credits through an RX_DATA_ACK CPL message. Returns the number of
 * credits sent.
 */
static u32 send_rx_credits(struct cxgbi_sock *csk, u32 credits)
{
        struct sk_buff *skb;
        struct cpl_rx_data_ack *req;
        u32 dack = F_RX_DACK_CHANGE | V_RX_DACK_MODE(1);

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_PDU_RX,
                "csk 0x%p,%u,0x%lx,%u, credit %u, dack %u.\n",
                csk, csk->state, csk->flags, csk->tid, credits, dack);

        skb = alloc_wr(sizeof(*req), 0, GFP_ATOMIC);
        if (!skb) {
                pr_info("csk 0x%p, credit %u, OOM.\n", csk, credits);
                return 0;
        }
        req = (struct cpl_rx_data_ack *)skb->head;
        req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
        OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_RX_DATA_ACK, csk->tid));
        req->credit_dack = htonl(F_RX_DACK_CHANGE | V_RX_DACK_MODE(1) |
                                V_RX_CREDITS(credits));
        skb->priority = CPL_PRIORITY_ACK;
        cxgb3_ofld_send(csk->cdev->lldev, skb);
        return credits;
}

/*
 * CPL connection tx data: host ->
 *
 * Send iscsi PDU via TX_DATA CPL message. Returns the number of
 * credits sent.
 * Each TX_DATA consumes work request credit (wrs), so we need to keep track of
 * how many we've used so far and how many are pending (i.e., yet ack'ed by T3).
 */

static unsigned int wrlen __read_mostly;
static unsigned int skb_wrs[SKB_WR_LIST_SIZE] __read_mostly;

static void init_wr_tab(unsigned int wr_len)
{
        int i;

        if (skb_wrs[1])         /* already initialized */
                return;
        for (i = 1; i < SKB_WR_LIST_SIZE; i++) {
                int sgl_len = (3 * i) / 2 + (i & 1);

                sgl_len += 3;
                skb_wrs[i] = (sgl_len <= wr_len
                              ? 1 : 1 + (sgl_len - 2) / (wr_len - 1));
        }
        wrlen = wr_len * 8;
}

static inline void make_tx_data_wr(struct cxgbi_sock *csk, struct sk_buff *skb,
                                   int len, int req_completion)
{
        struct tx_data_wr *req;
        struct l2t_entry *l2t = csk->l2t;

        skb_reset_transport_header(skb);
        req = __skb_push(skb, sizeof(*req));
        req->wr_hi = htonl(V_WR_OP(FW_WROPCODE_OFLD_TX_DATA) |
                        (req_completion ? F_WR_COMPL : 0));
        req->wr_lo = htonl(V_WR_TID(csk->tid));
        /* len includes the length of any HW ULP additions */
        req->len = htonl(len);
        /* V_TX_ULP_SUBMODE sets both the mode and submode */
        req->flags = htonl(V_TX_ULP_SUBMODE(cxgbi_skcb_ulp_mode(skb)) |
                           V_TX_SHOVE((skb_peek(&csk->write_queue) ? 0 : 1)));
        req->sndseq = htonl(csk->snd_nxt);
        req->param = htonl(V_TX_PORT(l2t->smt_idx));

        if (!cxgbi_sock_flag(csk, CTPF_TX_DATA_SENT)) {
                req->flags |= htonl(V_TX_ACK_PAGES(2) | F_TX_INIT |
                                    V_TX_CPU_IDX(csk->rss_qid));
                /* sendbuffer is in units of 32KB. */
                req->param |= htonl(V_TX_SNDBUF(csk->snd_win >> 15));
                cxgbi_sock_set_flag(csk, CTPF_TX_DATA_SENT);
        }
}

/**
 * push_tx_frames -- start transmit
 * @c3cn: the offloaded connection
 * @req_completion: request wr_ack or not
 *
 * Prepends TX_DATA_WR or CPL_CLOSE_CON_REQ headers to buffers waiting in a
 * connection's send queue and sends them on to T3.  Must be called with the
 * connection's lock held.  Returns the amount of send buffer space that was
 * freed as a result of sending queued data to T3.
 */

static void arp_failure_skb_discard(struct t3cdev *dev, struct sk_buff *skb)
{
        kfree_skb(skb);
}

static int push_tx_frames(struct cxgbi_sock *csk, int req_completion)
{
        int total_size = 0;
        struct sk_buff *skb;

        if (unlikely(csk->state < CTP_ESTABLISHED ||
                csk->state == CTP_CLOSE_WAIT_1 || csk->state >= CTP_ABORTING)) {
                        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_PDU_TX,
                                "csk 0x%p,%u,0x%lx,%u, in closing state.\n",
                                csk, csk->state, csk->flags, csk->tid);
                return 0;
        }

        while (csk->wr_cred && (skb = skb_peek(&csk->write_queue)) != NULL) {
                int len = skb->len;     /* length before skb_push */
                int frags = skb_shinfo(skb)->nr_frags + (len != skb->data_len);
                int wrs_needed = skb_wrs[frags];

                if (wrs_needed > 1 && len + sizeof(struct tx_data_wr) <= wrlen)
                        wrs_needed = 1;

                WARN_ON(frags >= SKB_WR_LIST_SIZE || wrs_needed < 1);

                if (csk->wr_cred < wrs_needed) {
                        log_debug(1 << CXGBI_DBG_PDU_TX,
                                "csk 0x%p, skb len %u/%u, frag %u, wr %d<%u.\n",
                                csk, skb->len, skb->data_len, frags,
                                wrs_needed, csk->wr_cred);
                        break;
                }

                __skb_unlink(skb, &csk->write_queue);
                skb->priority = CPL_PRIORITY_DATA;
                skb->csum = wrs_needed; /* remember this until the WR_ACK */
                csk->wr_cred -= wrs_needed;
                csk->wr_una_cred += wrs_needed;
                cxgbi_sock_enqueue_wr(csk, skb);

                log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_PDU_TX,
                        "csk 0x%p, enqueue, skb len %u/%u, frag %u, wr %d, "
                        "left %u, unack %u.\n",
                        csk, skb->len, skb->data_len, frags, skb->csum,
                        csk->wr_cred, csk->wr_una_cred);

                if (likely(cxgbi_skcb_test_flag(skb, SKCBF_TX_NEED_HDR))) {
                        if ((req_completion &&
                                csk->wr_una_cred == wrs_needed) ||
                             csk->wr_una_cred >= csk->wr_max_cred / 2) {
                                req_completion = 1;
                                csk->wr_una_cred = 0;
                        }
                        len += cxgbi_ulp_extra_len(cxgbi_skcb_ulp_mode(skb));
                        make_tx_data_wr(csk, skb, len, req_completion);
                        csk->snd_nxt += len;
                        cxgbi_skcb_clear_flag(skb, SKCBF_TX_NEED_HDR);
                }
                total_size += skb->truesize;
                log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_PDU_TX,
                        "csk 0x%p, tid 0x%x, send skb 0x%p.\n",
                        csk, csk->tid, skb);
                set_arp_failure_handler(skb, arp_failure_skb_discard);
                l2t_send(csk->cdev->lldev, skb, csk->l2t);
        }
        return total_size;
}

/*
 * Process a CPL_ACT_ESTABLISH message: -> host
 * Updates connection state from an active establish CPL message.  Runs with
 * the connection lock held.
 */

static inline void free_atid(struct cxgbi_sock *csk)
{
        if (cxgbi_sock_flag(csk, CTPF_HAS_ATID)) {
                cxgb3_free_atid(csk->cdev->lldev, csk->atid);
                cxgbi_sock_clear_flag(csk, CTPF_HAS_ATID);
                cxgbi_sock_put(csk);
        }
}

static int do_act_establish(struct t3cdev *tdev, struct sk_buff *skb, void *ctx)
{
        struct cxgbi_sock *csk = ctx;
        struct cpl_act_establish *req = cplhdr(skb);
        unsigned int tid = GET_TID(req);
        unsigned int atid = G_PASS_OPEN_TID(ntohl(req->tos_tid));
        u32 rcv_isn = ntohl(req->rcv_isn);      /* real RCV_ISN + 1 */

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "atid 0x%x,tid 0x%x, csk 0x%p,%u,0x%lx, isn %u.\n",
                atid, atid, csk, csk->state, csk->flags, rcv_isn);

        cxgbi_sock_get(csk);
        cxgbi_sock_set_flag(csk, CTPF_HAS_TID);
        csk->tid = tid;
        cxgb3_insert_tid(csk->cdev->lldev, &t3_client, csk, tid);

        free_atid(csk);

        csk->rss_qid = G_QNUM(ntohs(skb->csum));

        spin_lock_bh(&csk->lock);
        if (csk->retry_timer.function) {
                del_timer(&csk->retry_timer);
                csk->retry_timer.function = NULL;
        }

        if (unlikely(csk->state != CTP_ACTIVE_OPEN))
                pr_info("csk 0x%p,%u,0x%lx,%u, got EST.\n",
                        csk, csk->state, csk->flags, csk->tid);

        csk->copied_seq = csk->rcv_wup = csk->rcv_nxt = rcv_isn;
        if (csk->rcv_win > (M_RCV_BUFSIZ << 10))
                csk->rcv_wup -= csk->rcv_win - (M_RCV_BUFSIZ << 10);

        cxgbi_sock_established(csk, ntohl(req->snd_isn), ntohs(req->tcp_opt));

        if (unlikely(cxgbi_sock_flag(csk, CTPF_ACTIVE_CLOSE_NEEDED)))
                /* upper layer has requested closing */
                send_abort_req(csk);
        else {
                if (skb_queue_len(&csk->write_queue))
                        push_tx_frames(csk, 1);
                cxgbi_conn_tx_open(csk);
        }

        spin_unlock_bh(&csk->lock);
        __kfree_skb(skb);
        return 0;
}

/*
 * Process a CPL_ACT_OPEN_RPL message: -> host
 * Handle active open failures.
 */
static int act_open_rpl_status_to_errno(int status)
{
        switch (status) {
        case CPL_ERR_CONN_RESET:
                return -ECONNREFUSED;
        case CPL_ERR_ARP_MISS:
                return -EHOSTUNREACH;
        case CPL_ERR_CONN_TIMEDOUT:
                return -ETIMEDOUT;
        case CPL_ERR_TCAM_FULL:
                return -ENOMEM;
        case CPL_ERR_CONN_EXIST:
                return -EADDRINUSE;
        default:
                return -EIO;
        }
}

static void act_open_retry_timer(struct timer_list *t)
{
        struct cxgbi_sock *csk = from_timer(csk, t, retry_timer);
        struct sk_buff *skb;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx,%u.\n",
                csk, csk->state, csk->flags, csk->tid);

        cxgbi_sock_get(csk);
        spin_lock_bh(&csk->lock);
        skb = alloc_wr(sizeof(struct cpl_act_open_req), 0, GFP_ATOMIC);
        if (!skb)
                cxgbi_sock_fail_act_open(csk, -ENOMEM);
        else {
                skb->sk = (struct sock *)csk;
                set_arp_failure_handler(skb, act_open_arp_failure);
                send_act_open_req(csk, skb, csk->l2t);
        }
        spin_unlock_bh(&csk->lock);
        cxgbi_sock_put(csk);
}

static int do_act_open_rpl(struct t3cdev *tdev, struct sk_buff *skb, void *ctx)
{
        struct cxgbi_sock *csk = ctx;
        struct cpl_act_open_rpl *rpl = cplhdr(skb);

        pr_info("csk 0x%p,%u,0x%lx,%u, status %u, %pI4:%u-%pI4:%u.\n",
                csk, csk->state, csk->flags, csk->atid, rpl->status,
                &csk->saddr.sin_addr.s_addr, ntohs(csk->saddr.sin_port),
                &csk->daddr.sin_addr.s_addr, ntohs(csk->daddr.sin_port));

        if (rpl->status != CPL_ERR_TCAM_FULL &&
            rpl->status != CPL_ERR_CONN_EXIST &&
            rpl->status != CPL_ERR_ARP_MISS)
                cxgb3_queue_tid_release(tdev, GET_TID(rpl));

        cxgbi_sock_get(csk);
        spin_lock_bh(&csk->lock);
        if (rpl->status == CPL_ERR_CONN_EXIST &&
            csk->retry_timer.function != act_open_retry_timer) {
                csk->retry_timer.function = act_open_retry_timer;
                mod_timer(&csk->retry_timer, jiffies + HZ / 2);
        } else
                cxgbi_sock_fail_act_open(csk,
                                act_open_rpl_status_to_errno(rpl->status));

        spin_unlock_bh(&csk->lock);
        cxgbi_sock_put(csk);
        __kfree_skb(skb);
        return 0;
}

/*
 * Process PEER_CLOSE CPL messages: -> host
 * Handle peer FIN.
 */
static int do_peer_close(struct t3cdev *cdev, struct sk_buff *skb, void *ctx)
{
        struct cxgbi_sock *csk = ctx;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx,%u.\n",
                csk, csk->state, csk->flags, csk->tid);

        cxgbi_sock_rcv_peer_close(csk);
        __kfree_skb(skb);
        return 0;
}

/*
 * Process CLOSE_CONN_RPL CPL message: -> host
 * Process a peer ACK to our FIN.
 */
static int do_close_con_rpl(struct t3cdev *cdev, struct sk_buff *skb,
                            void *ctx)
{
        struct cxgbi_sock *csk = ctx;
        struct cpl_close_con_rpl *rpl = cplhdr(skb);

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx,%u, snxt %u.\n",
                csk, csk->state, csk->flags, csk->tid, ntohl(rpl->snd_nxt));

        cxgbi_sock_rcv_close_conn_rpl(csk, ntohl(rpl->snd_nxt));
        __kfree_skb(skb);
        return 0;
}

/*
 * Process ABORT_REQ_RSS CPL message: -> host
 * Process abort requests.  If we are waiting for an ABORT_RPL we ignore this
 * request except that we need to reply to it.
 */

static int abort_status_to_errno(struct cxgbi_sock *csk, int abort_reason,
                                 int *need_rst)
{
        switch (abort_reason) {
        case CPL_ERR_BAD_SYN: /* fall through */
        case CPL_ERR_CONN_RESET:
                return csk->state > CTP_ESTABLISHED ? -EPIPE : -ECONNRESET;
        case CPL_ERR_XMIT_TIMEDOUT:
        case CPL_ERR_PERSIST_TIMEDOUT:
        case CPL_ERR_FINWAIT2_TIMEDOUT:
        case CPL_ERR_KEEPALIVE_TIMEDOUT:
                return -ETIMEDOUT;
        default:
                return -EIO;
        }
}

static int do_abort_req(struct t3cdev *cdev, struct sk_buff *skb, void *ctx)
{
        const struct cpl_abort_req_rss *req = cplhdr(skb);
        struct cxgbi_sock *csk = ctx;
        int rst_status = CPL_ABORT_NO_RST;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx,%u.\n",
                csk, csk->state, csk->flags, csk->tid);

        if (req->status == CPL_ERR_RTX_NEG_ADVICE ||
            req->status == CPL_ERR_PERSIST_NEG_ADVICE) {
                goto done;
        }

        cxgbi_sock_get(csk);
        spin_lock_bh(&csk->lock);

        if (!cxgbi_sock_flag(csk, CTPF_ABORT_REQ_RCVD)) {
                cxgbi_sock_set_flag(csk, CTPF_ABORT_REQ_RCVD);
                cxgbi_sock_set_state(csk, CTP_ABORTING);
                goto out;
        }

        cxgbi_sock_clear_flag(csk, CTPF_ABORT_REQ_RCVD);
        send_abort_rpl(csk, rst_status);

        if (!cxgbi_sock_flag(csk, CTPF_ABORT_RPL_PENDING)) {
                csk->err = abort_status_to_errno(csk, req->status, &rst_status);
                cxgbi_sock_closed(csk);
        }

out:
        spin_unlock_bh(&csk->lock);
        cxgbi_sock_put(csk);
done:
        __kfree_skb(skb);
        return 0;
}

/*
 * Process ABORT_RPL_RSS CPL message: -> host
 * Process abort replies.  We only process these messages if we anticipate
 * them as the coordination between SW and HW in this area is somewhat lacking
 * and sometimes we get ABORT_RPLs after we are done with the connection that
 * originated the ABORT_REQ.
 */
static int do_abort_rpl(struct t3cdev *cdev, struct sk_buff *skb, void *ctx)
{
        struct cpl_abort_rpl_rss *rpl = cplhdr(skb);
        struct cxgbi_sock *csk = ctx;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "status 0x%x, csk 0x%p, s %u, 0x%lx.\n",
                rpl->status, csk, csk ? csk->state : 0,
                csk ? csk->flags : 0UL);
        /*
         * Ignore replies to post-close aborts indicating that the abort was
         * requested too late.  These connections are terminated when we get
         * PEER_CLOSE or CLOSE_CON_RPL and by the time the abort_rpl_rss
         * arrives the TID is either no longer used or it has been recycled.
         */
        if (rpl->status == CPL_ERR_ABORT_FAILED)
                goto rel_skb;
        /*
         * Sometimes we've already closed the connection, e.g., a post-close
         * abort races with ABORT_REQ_RSS, the latter frees the connection
         * expecting the ABORT_REQ will fail with CPL_ERR_ABORT_FAILED,
         * but FW turns the ABORT_REQ into a regular one and so we get
         * ABORT_RPL_RSS with status 0 and no connection.
         */
        if (csk)
                cxgbi_sock_rcv_abort_rpl(csk);
rel_skb:
        __kfree_skb(skb);
        return 0;
}

/*
 * Process RX_ISCSI_HDR CPL message: -> host
 * Handle received PDUs, the payload could be DDP'ed. If not, the payload
 * follow after the bhs.
 */
static int do_iscsi_hdr(struct t3cdev *t3dev, struct sk_buff *skb, void *ctx)
{
        struct cxgbi_sock *csk = ctx;
        struct cpl_iscsi_hdr *hdr_cpl = cplhdr(skb);
        struct cpl_iscsi_hdr_norss data_cpl;
        struct cpl_rx_data_ddp_norss ddp_cpl;
        unsigned int hdr_len, data_len, status;
        unsigned int len;
        int err;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_PDU_RX,
                "csk 0x%p,%u,0x%lx,%u, skb 0x%p,%u.\n",
                csk, csk->state, csk->flags, csk->tid, skb, skb->len);

        spin_lock_bh(&csk->lock);

        if (unlikely(csk->state >= CTP_PASSIVE_CLOSE)) {
                log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                        "csk 0x%p,%u,0x%lx,%u, bad state.\n",
                        csk, csk->state, csk->flags, csk->tid);
                if (csk->state != CTP_ABORTING)
                        goto abort_conn;
                else
                        goto discard;
        }

        cxgbi_skcb_tcp_seq(skb) = ntohl(hdr_cpl->seq);
        cxgbi_skcb_flags(skb) = 0;

        skb_reset_transport_header(skb);
        __skb_pull(skb, sizeof(struct cpl_iscsi_hdr));

        len = hdr_len = ntohs(hdr_cpl->len);
        /* msg coalesce is off or not enough data received */
        if (skb->len <= hdr_len) {
                pr_err("%s: tid %u, CPL_ISCSI_HDR, skb len %u < %u.\n",
                        csk->cdev->ports[csk->port_id]->name, csk->tid,
                        skb->len, hdr_len);
                goto abort_conn;
        }
        cxgbi_skcb_set_flag(skb, SKCBF_RX_COALESCED);

        err = skb_copy_bits(skb, skb->len - sizeof(ddp_cpl), &ddp_cpl,
                            sizeof(ddp_cpl));
        if (err < 0) {
                pr_err("%s: tid %u, copy cpl_ddp %u-%zu failed %d.\n",
                        csk->cdev->ports[csk->port_id]->name, csk->tid,
                        skb->len, sizeof(ddp_cpl), err);
                goto abort_conn;
        }

        cxgbi_skcb_set_flag(skb, SKCBF_RX_STATUS);
        cxgbi_skcb_rx_pdulen(skb) = ntohs(ddp_cpl.len);
        cxgbi_skcb_rx_ddigest(skb) = ntohl(ddp_cpl.ulp_crc);
        status = ntohl(ddp_cpl.ddp_status);

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_PDU_RX,
                "csk 0x%p, skb 0x%p,%u, pdulen %u, status 0x%x.\n",
                csk, skb, skb->len, cxgbi_skcb_rx_pdulen(skb), status);

        if (status & (1 << CPL_RX_DDP_STATUS_HCRC_SHIFT))
                cxgbi_skcb_set_flag(skb, SKCBF_RX_HCRC_ERR);
        if (status & (1 << CPL_RX_DDP_STATUS_DCRC_SHIFT))
                cxgbi_skcb_set_flag(skb, SKCBF_RX_DCRC_ERR);
        if (status & (1 << CPL_RX_DDP_STATUS_PAD_SHIFT))
                cxgbi_skcb_set_flag(skb, SKCBF_RX_PAD_ERR);

        if (skb->len > (hdr_len + sizeof(ddp_cpl))) {
                err = skb_copy_bits(skb, hdr_len, &data_cpl, sizeof(data_cpl));
                if (err < 0) {
                        pr_err("%s: tid %u, cp %zu/%u failed %d.\n",
                                csk->cdev->ports[csk->port_id]->name,
                                csk->tid, sizeof(data_cpl), skb->len, err);
                        goto abort_conn;
                }
                data_len = ntohs(data_cpl.len);
                log_debug(1 << CXGBI_DBG_DDP | 1 << CXGBI_DBG_PDU_RX,
                        "skb 0x%p, pdu not ddp'ed %u/%u, status 0x%x.\n",
                        skb, data_len, cxgbi_skcb_rx_pdulen(skb), status);
                len += sizeof(data_cpl) + data_len;
        } else if (status & (1 << CPL_RX_DDP_STATUS_DDP_SHIFT))
                cxgbi_skcb_set_flag(skb, SKCBF_RX_DATA_DDPD);

        csk->rcv_nxt = ntohl(ddp_cpl.seq) + cxgbi_skcb_rx_pdulen(skb);
        __pskb_trim(skb, len);
        __skb_queue_tail(&csk->receive_queue, skb);
        cxgbi_conn_pdu_ready(csk);

        spin_unlock_bh(&csk->lock);
        return 0;

abort_conn:
        send_abort_req(csk);
discard:
        spin_unlock_bh(&csk->lock);
        __kfree_skb(skb);
        return 0;
}

/*
 * Process TX_DATA_ACK CPL messages: -> host
 * Process an acknowledgment of WR completion.  Advance snd_una and send the
 * next batch of work requests from the write queue.
 */
static int do_wr_ack(struct t3cdev *cdev, struct sk_buff *skb, void *ctx)
{
        struct cxgbi_sock *csk = ctx;
        struct cpl_wr_ack *hdr = cplhdr(skb);

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_PDU_RX,
                "csk 0x%p,%u,0x%lx,%u, cr %u.\n",
                csk, csk->state, csk->flags, csk->tid, ntohs(hdr->credits));

        cxgbi_sock_rcv_wr_ack(csk, ntohs(hdr->credits), ntohl(hdr->snd_una), 1);
        __kfree_skb(skb);
        return 0;
}

/*
 * for each connection, pre-allocate skbs needed for close/abort requests. So
 * that we can service the request right away.
 */
static int alloc_cpls(struct cxgbi_sock *csk)
{
        csk->cpl_close = alloc_wr(sizeof(struct cpl_close_con_req), 0,
                                        GFP_KERNEL);
        if (!csk->cpl_close)
                return -ENOMEM;
        csk->cpl_abort_req = alloc_wr(sizeof(struct cpl_abort_req), 0,
                                        GFP_KERNEL);
        if (!csk->cpl_abort_req)
                goto free_cpl_skbs;

        csk->cpl_abort_rpl = alloc_wr(sizeof(struct cpl_abort_rpl), 0,
                                        GFP_KERNEL);
        if (!csk->cpl_abort_rpl)
                goto free_cpl_skbs;

        return 0;

free_cpl_skbs:
        cxgbi_sock_free_cpl_skbs(csk);
        return -ENOMEM;
}

/**
 * release_offload_resources - release offload resource
 * @c3cn: the offloaded iscsi tcp connection.
 * Release resources held by an offload connection (TID, L2T entry, etc.)
 */
static void l2t_put(struct cxgbi_sock *csk)
{
        struct t3cdev *t3dev = (struct t3cdev *)csk->cdev->lldev;

        if (csk->l2t) {
                l2t_release(t3dev, csk->l2t);
                csk->l2t = NULL;
                cxgbi_sock_put(csk);
        }
}

static void release_offload_resources(struct cxgbi_sock *csk)
{
        struct t3cdev *t3dev = (struct t3cdev *)csk->cdev->lldev;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx,%u.\n",
                csk, csk->state, csk->flags, csk->tid);

        csk->rss_qid = 0;
        cxgbi_sock_free_cpl_skbs(csk);

        if (csk->wr_cred != csk->wr_max_cred) {
                cxgbi_sock_purge_wr_queue(csk);
                cxgbi_sock_reset_wr_list(csk);
        }
        l2t_put(csk);
        if (cxgbi_sock_flag(csk, CTPF_HAS_ATID))
                free_atid(csk);
        else if (cxgbi_sock_flag(csk, CTPF_HAS_TID)) {
                cxgb3_remove_tid(t3dev, (void *)csk, csk->tid);
                cxgbi_sock_clear_flag(csk, CTPF_HAS_TID);
                cxgbi_sock_put(csk);
        }
        csk->dst = NULL;
        csk->cdev = NULL;
}

static void update_address(struct cxgbi_hba *chba)
{
        if (chba->ipv4addr) {
                if (chba->vdev &&
                    chba->ipv4addr != cxgb3i_get_private_ipv4addr(chba->vdev)) {
                        cxgb3i_set_private_ipv4addr(chba->vdev, chba->ipv4addr);
                        cxgb3i_set_private_ipv4addr(chba->ndev, 0);
                        pr_info("%s set %pI4.\n",
                                chba->vdev->name, &chba->ipv4addr);
                } else if (chba->ipv4addr !=
                                cxgb3i_get_private_ipv4addr(chba->ndev)) {
                        cxgb3i_set_private_ipv4addr(chba->ndev, chba->ipv4addr);
                        pr_info("%s set %pI4.\n",
                                chba->ndev->name, &chba->ipv4addr);
                }
        } else if (cxgb3i_get_private_ipv4addr(chba->ndev)) {
                if (chba->vdev)
                        cxgb3i_set_private_ipv4addr(chba->vdev, 0);
                cxgb3i_set_private_ipv4addr(chba->ndev, 0);
        }
}

static int init_act_open(struct cxgbi_sock *csk)
{
        struct dst_entry *dst = csk->dst;
        struct cxgbi_device *cdev = csk->cdev;
        struct t3cdev *t3dev = (struct t3cdev *)cdev->lldev;
        struct net_device *ndev = cdev->ports[csk->port_id];
        struct cxgbi_hba *chba = cdev->hbas[csk->port_id];
        struct sk_buff *skb = NULL;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx.\n", csk, csk->state, csk->flags);

        update_address(chba);
        if (chba->ipv4addr)
                csk->saddr.sin_addr.s_addr = chba->ipv4addr;

        csk->rss_qid = 0;
        csk->l2t = t3_l2t_get(t3dev, dst, ndev,
                              &csk->daddr.sin_addr.s_addr);
        if (!csk->l2t) {
                pr_err("NO l2t available.\n");
                return -EINVAL;
        }
        cxgbi_sock_get(csk);

        csk->atid = cxgb3_alloc_atid(t3dev, &t3_client, csk);
        if (csk->atid < 0) {
                pr_err("NO atid available.\n");
                goto rel_resource;
        }
        cxgbi_sock_set_flag(csk, CTPF_HAS_ATID);
        cxgbi_sock_get(csk);

        skb = alloc_wr(sizeof(struct cpl_act_open_req), 0, GFP_KERNEL);
        if (!skb)
                goto rel_resource;
        skb->sk = (struct sock *)csk;
        set_arp_failure_handler(skb, act_open_arp_failure);
        csk->snd_win = cxgb3i_snd_win;
        csk->rcv_win = cxgb3i_rcv_win;

        csk->wr_max_cred = csk->wr_cred = T3C_DATA(t3dev)->max_wrs - 1;
        csk->wr_una_cred = 0;
        csk->mss_idx = cxgbi_sock_select_mss(csk, dst_mtu(dst));
        cxgbi_sock_reset_wr_list(csk);
        csk->err = 0;

        log_debug(1 << CXGBI_DBG_TOE | 1 << CXGBI_DBG_SOCK,
                "csk 0x%p,%u,0x%lx, %pI4:%u-%pI4:%u.\n",
                csk, csk->state, csk->flags,
                &csk->saddr.sin_addr.s_addr, ntohs(csk->saddr.sin_port),
                &csk->daddr.sin_addr.s_addr, ntohs(csk->daddr.sin_port));

        cxgbi_sock_set_state(csk, CTP_ACTIVE_OPEN);
        send_act_open_req(csk, skb, csk->l2t);
        return 0;

rel_resource:
        if (skb)
                __kfree_skb(skb);
        return -EINVAL;
}

cxgb3_cpl_handler_func cxgb3i_cpl_handlers[NUM_CPL_CMDS] = {
        [CPL_ACT_ESTABLISH] = do_act_establish,
        [CPL_ACT_OPEN_RPL] = do_act_open_rpl,
        [CPL_PEER_CLOSE] = do_peer_close,
        [CPL_ABORT_REQ_RSS] = do_abort_req,
        [CPL_ABORT_RPL_RSS] = do_abort_rpl,
        [CPL_CLOSE_CON_RPL] = do_close_con_rpl,
        [CPL_TX_DMA_ACK] = do_wr_ack,
        [CPL_ISCSI_HDR] = do_iscsi_hdr,
};

/**
 * cxgb3i_ofld_init - allocate and initialize resources for each adapter found
 * @cdev:       cxgbi adapter
 */
static int cxgb3i_ofld_init(struct cxgbi_device *cdev)
{
        struct t3cdev *t3dev = (struct t3cdev *)cdev->lldev;
        struct adap_ports port;
        struct ofld_page_info rx_page_info;
        unsigned int wr_len;
        int rc;

        if (t3dev->ctl(t3dev, GET_WR_LEN, &wr_len) < 0 ||
            t3dev->ctl(t3dev, GET_PORTS, &port) < 0 ||
            t3dev->ctl(t3dev, GET_RX_PAGE_INFO, &rx_page_info) < 0) {
                pr_warn("t3 0x%p, offload up, ioctl failed.\n", t3dev);
                return -EINVAL;
        }

        if (cxgb3i_max_connect > CXGBI_MAX_CONN)
                cxgb3i_max_connect = CXGBI_MAX_CONN;

        rc = cxgbi_device_portmap_create(cdev, cxgb3i_sport_base,
                                        cxgb3i_max_connect);
        if (rc < 0)
                return rc;

        init_wr_tab(wr_len);
        cdev->csk_release_offload_resources = release_offload_resources;
        cdev->csk_push_tx_frames = push_tx_frames;
        cdev->csk_send_abort_req = send_abort_req;
        cdev->csk_send_close_req = send_close_req;
        cdev->csk_send_rx_credits = send_rx_credits;
        cdev->csk_alloc_cpls = alloc_cpls;
        cdev->csk_init_act_open = init_act_open;

        pr_info("cdev 0x%p, offload up, added.\n", cdev);
        return 0;
}

/*
 * functions to program the pagepod in h/w
 */
static inline void ulp_mem_io_set_hdr(struct sk_buff *skb, unsigned int addr)
{
        struct ulp_mem_io *req = (struct ulp_mem_io *)skb->head;

        memset(req, 0, sizeof(*req));

        req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_BYPASS));
        req->cmd_lock_addr = htonl(V_ULP_MEMIO_ADDR(addr >> 5) |
                                   V_ULPTX_CMD(ULP_MEM_WRITE));
        req->len = htonl(V_ULP_MEMIO_DATA_LEN(IPPOD_SIZE >> 5) |
                         V_ULPTX_NFLITS((IPPOD_SIZE >> 3) + 1));
}

static struct cxgbi_ppm *cdev2ppm(struct cxgbi_device *cdev)
{
        return ((struct t3cdev *)cdev->lldev)->ulp_iscsi;
}

static int ddp_set_map(struct cxgbi_ppm *ppm, struct cxgbi_sock *csk,
                       struct cxgbi_task_tag_info *ttinfo)
{
        unsigned int idx = ttinfo->idx;
        unsigned int npods = ttinfo->npods;
        struct scatterlist *sg = ttinfo->sgl;
        struct cxgbi_pagepod *ppod;
        struct ulp_mem_io *req;
        unsigned int sg_off;
        unsigned int pm_addr = (idx << PPOD_SIZE_SHIFT) + ppm->llimit;
        int i;

        for (i = 0; i < npods; i++, idx++, pm_addr += IPPOD_SIZE) {
                struct sk_buff *skb = alloc_wr(sizeof(struct ulp_mem_io) +
                                               IPPOD_SIZE, 0, GFP_ATOMIC);

                if (!skb)
                        return -ENOMEM;
                ulp_mem_io_set_hdr(skb, pm_addr);
                req = (struct ulp_mem_io *)skb->head;
                ppod = (struct cxgbi_pagepod *)(req + 1);
                sg_off = i * PPOD_PAGES_MAX;
                cxgbi_ddp_set_one_ppod(ppod, ttinfo, &sg,
                                       &sg_off);
                skb->priority = CPL_PRIORITY_CONTROL;
                cxgb3_ofld_send(ppm->lldev, skb);
        }
        return 0;
}

static void ddp_clear_map(struct cxgbi_device *cdev, struct cxgbi_ppm *ppm,
                          struct cxgbi_task_tag_info *ttinfo)
{
        unsigned int idx = ttinfo->idx;
        unsigned int pm_addr = (idx << PPOD_SIZE_SHIFT) + ppm->llimit;
        unsigned int npods = ttinfo->npods;
        int i;

        log_debug(1 << CXGBI_DBG_DDP,
                  "cdev 0x%p, clear idx %u, npods %u.\n",
                  cdev, idx, npods);

        for (i = 0; i < npods; i++, idx++, pm_addr += IPPOD_SIZE) {
                struct sk_buff *skb = alloc_wr(sizeof(struct ulp_mem_io) +
                                               IPPOD_SIZE, 0, GFP_ATOMIC);

                if (!skb) {
                        pr_err("cdev 0x%p, clear ddp, %u,%d/%u, skb OOM.\n",
                               cdev, idx, i, npods);
                        continue;
                }
                ulp_mem_io_set_hdr(skb, pm_addr);
                skb->priority = CPL_PRIORITY_CONTROL;
                cxgb3_ofld_send(ppm->lldev, skb);
        }
}

static int ddp_setup_conn_pgidx(struct cxgbi_sock *csk,
                                       unsigned int tid, int pg_idx, bool reply)
{
        struct sk_buff *skb = alloc_wr(sizeof(struct cpl_set_tcb_field), 0,
                                        GFP_KERNEL);
        struct cpl_set_tcb_field *req;
        u64 val = pg_idx < DDP_PGIDX_MAX ? pg_idx : 0;

        log_debug(1 << CXGBI_DBG_DDP,
                "csk 0x%p, tid %u, pg_idx %d.\n", csk, tid, pg_idx);
        if (!skb)
                return -ENOMEM;

        /* set up ulp submode and page size */
        req = (struct cpl_set_tcb_field *)skb->head;
        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 = V_NO_REPLY(reply ? 0 : 1);
        req->cpu_idx = 0;
        req->word = htons(31);
        req->mask = cpu_to_be64(0xF0000000);
        req->val = cpu_to_be64(val << 28);
        skb->priority = CPL_PRIORITY_CONTROL;

        cxgb3_ofld_send(csk->cdev->lldev, skb);
        return 0;
}

/**
 * cxgb3i_setup_conn_digest - setup conn. digest setting
 * @csk: cxgb tcp socket
 * @tid: connection id
 * @hcrc: header digest enabled
 * @dcrc: data digest enabled
 * @reply: request reply from h/w
 * set up the iscsi digest settings for a connection identified by tid
 */
static int ddp_setup_conn_digest(struct cxgbi_sock *csk, unsigned int tid,
                             int hcrc, int dcrc, int reply)
{
        struct sk_buff *skb = alloc_wr(sizeof(struct cpl_set_tcb_field), 0,
                                        GFP_KERNEL);
        struct cpl_set_tcb_field *req;
        u64 val = (hcrc ? 1 : 0) | (dcrc ? 2 : 0);

        log_debug(1 << CXGBI_DBG_DDP,
                "csk 0x%p, tid %u, crc %d,%d.\n", csk, tid, hcrc, dcrc);
        if (!skb)
                return -ENOMEM;

        /* set up ulp submode and page size */
        req = (struct cpl_set_tcb_field *)skb->head;
        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 = V_NO_REPLY(reply ? 0 : 1);
        req->cpu_idx = 0;
        req->word = htons(31);
        req->mask = cpu_to_be64(0x0F000000);
        req->val = cpu_to_be64(val << 24);
        skb->priority = CPL_PRIORITY_CONTROL;

        cxgb3_ofld_send(csk->cdev->lldev, skb);
        return 0;
}

/**
 * cxgb3i_ddp_init - initialize the cxgb3 adapter's ddp resource
 * @cdev: cxgb3i adapter
 * initialize the ddp pagepod manager for a given adapter
 */
static int cxgb3i_ddp_init(struct cxgbi_device *cdev)
{
        struct t3cdev *tdev = (struct t3cdev *)cdev->lldev;
        struct net_device *ndev = cdev->ports[0];
        struct cxgbi_tag_format tformat;
        unsigned int ppmax, tagmask = 0;
        struct ulp_iscsi_info uinfo;
        int i, err;

        err = tdev->ctl(tdev, ULP_ISCSI_GET_PARAMS, &uinfo);
        if (err < 0) {
                pr_err("%s, failed to get iscsi param %d.\n",
                       ndev->name, err);
                return err;
        }
        if (uinfo.llimit >= uinfo.ulimit) {
                pr_warn("T3 %s, iscsi NOT enabled %u ~ %u!\n",
                        ndev->name, uinfo.llimit, uinfo.ulimit);
                return -EACCES;
        }

        ppmax = (uinfo.ulimit - uinfo.llimit + 1) >> PPOD_SIZE_SHIFT;
        tagmask = cxgbi_tagmask_set(ppmax);

        pr_info("T3 %s: 0x%x~0x%x, 0x%x, tagmask 0x%x -> 0x%x.\n",
                ndev->name, uinfo.llimit, uinfo.ulimit, ppmax, uinfo.tagmask,
                tagmask);

        memset(&tformat, 0, sizeof(struct cxgbi_tag_format));
        for (i = 0; i < 4; i++)
                tformat.pgsz_order[i] = uinfo.pgsz_factor[i];
        cxgbi_tagmask_check(tagmask, &tformat);

        cxgbi_ddp_ppm_setup(&tdev->ulp_iscsi, cdev, &tformat, ppmax,
                            uinfo.llimit, uinfo.llimit, 0);
        if (!(cdev->flags & CXGBI_FLAG_DDP_OFF)) {
                uinfo.tagmask = tagmask;
                uinfo.ulimit = uinfo.llimit + (ppmax << PPOD_SIZE_SHIFT);

                err = tdev->ctl(tdev, ULP_ISCSI_SET_PARAMS, &uinfo);
                if (err < 0) {
                        pr_err("T3 %s fail to set iscsi param %d.\n",
                               ndev->name, err);
                        cdev->flags |= CXGBI_FLAG_DDP_OFF;
                }
                err = 0;
        }

        cdev->csk_ddp_setup_digest = ddp_setup_conn_digest;
        cdev->csk_ddp_setup_pgidx = ddp_setup_conn_pgidx;
        cdev->csk_ddp_set_map = ddp_set_map;
        cdev->csk_ddp_clear_map = ddp_clear_map;
        cdev->cdev2ppm = cdev2ppm;
        cdev->tx_max_size = min_t(unsigned int, ULP2_MAX_PDU_PAYLOAD,
                                  uinfo.max_txsz - ISCSI_PDU_NONPAYLOAD_LEN);
        cdev->rx_max_size = min_t(unsigned int, ULP2_MAX_PDU_PAYLOAD,
                                  uinfo.max_rxsz - ISCSI_PDU_NONPAYLOAD_LEN);

        return 0;
}

static void cxgb3i_dev_close(struct t3cdev *t3dev)
{
        struct cxgbi_device *cdev = cxgbi_device_find_by_lldev(t3dev);

        if (!cdev || cdev->flags & CXGBI_FLAG_ADAPTER_RESET) {
                pr_info("0x%p close, f 0x%x.\n", cdev, cdev ? cdev->flags : 0);
                return;
        }

        cxgbi_device_unregister(cdev);
}

/**
 * cxgb3i_dev_open - init a t3 adapter structure and any h/w settings
 * @t3dev: t3cdev adapter
 */
static void cxgb3i_dev_open(struct t3cdev *t3dev)
{
        struct cxgbi_device *cdev = cxgbi_device_find_by_lldev(t3dev);
        struct adapter *adapter = tdev2adap(t3dev);
        int i, err;

        if (cdev) {
                pr_info("0x%p, updating.\n", cdev);
                return;
        }

        cdev = cxgbi_device_register(0, adapter->params.nports);
        if (!cdev) {
                pr_warn("device 0x%p register failed.\n", t3dev);
                return;
        }

        cdev->flags = CXGBI_FLAG_DEV_T3 | CXGBI_FLAG_IPV4_SET;
        cdev->lldev = t3dev;
        cdev->pdev = adapter->pdev;
        cdev->ports = adapter->port;
        cdev->nports = adapter->params.nports;
        cdev->mtus = adapter->params.mtus;
        cdev->nmtus = NMTUS;
        cdev->rx_credit_thres = cxgb3i_rx_credit_thres;
        cdev->skb_tx_rsvd = CXGB3I_TX_HEADER_LEN;
        cdev->skb_rx_extra = sizeof(struct cpl_iscsi_hdr_norss);
        cdev->itp = &cxgb3i_iscsi_transport;

        err = cxgb3i_ddp_init(cdev);
        if (err) {
                pr_info("0x%p ddp init failed\n", cdev);
                goto err_out;
        }

        err = cxgb3i_ofld_init(cdev);
        if (err) {
                pr_info("0x%p offload init failed\n", cdev);
                goto err_out;
        }

        err = cxgbi_hbas_add(cdev, CXGB3I_MAX_LUN, CXGBI_MAX_CONN,
                                &cxgb3i_host_template, cxgb3i_stt);
        if (err)
                goto err_out;

        for (i = 0; i < cdev->nports; i++)
                cdev->hbas[i]->ipv4addr =
                        cxgb3i_get_private_ipv4addr(cdev->ports[i]);

        pr_info("cdev 0x%p, f 0x%x, t3dev 0x%p open, err %d.\n",
                cdev, cdev ? cdev->flags : 0, t3dev, err);
        return;

err_out:
        cxgbi_device_unregister(cdev);
}

static void cxgb3i_dev_event_handler(struct t3cdev *t3dev, u32 event, u32 port)
{
        struct cxgbi_device *cdev = cxgbi_device_find_by_lldev(t3dev);

        log_debug(1 << CXGBI_DBG_TOE,
                "0x%p, cdev 0x%p, event 0x%x, port 0x%x.\n",
                t3dev, cdev, event, port);
        if (!cdev)
                return;

        switch (event) {
        case OFFLOAD_STATUS_DOWN:
                cdev->flags |= CXGBI_FLAG_ADAPTER_RESET;
                break;
        case OFFLOAD_STATUS_UP:
                cdev->flags &= ~CXGBI_FLAG_ADAPTER_RESET;
                break;
        }
}

/**
 * cxgb3i_init_module - module init entry point
 *
 * initialize any driver wide global data structures and register itself
 *      with the cxgb3 module
 */
static int __init cxgb3i_init_module(void)
{
        int rc;

        printk(KERN_INFO "%s", version);

        rc = cxgbi_iscsi_init(&cxgb3i_iscsi_transport, &cxgb3i_stt);
        if (rc < 0)
                return rc;

        cxgb3_register_client(&t3_client);
        return 0;
}

/**
 * cxgb3i_exit_module - module cleanup/exit entry point
 *
 * go through the driver hba list and for each hba, release any resource held.
 *      and unregisters iscsi transport and the cxgb3 module
 */
static void __exit cxgb3i_exit_module(void)
{
        cxgb3_unregister_client(&t3_client);
        cxgbi_device_unregister_all(CXGBI_FLAG_DEV_T3);
        cxgbi_iscsi_cleanup(&cxgb3i_iscsi_transport, &cxgb3i_stt);
}

module_init(cxgb3i_init_module);
module_exit(cxgb3i_exit_module);