/*
 *  qla_target.c SCSI LLD infrastructure for QLogic 22xx/23xx/24xx/25xx
 *
 *  based on qla2x00t.c code:
 *
 *  Copyright (C) 2004 - 2010 Vladislav Bolkhovitin <vst@vlnb.net>
 *  Copyright (C) 2004 - 2005 Leonid Stoljar
 *  Copyright (C) 2006 Nathaniel Clark <nate@misrule.us>
 *  Copyright (C) 2006 - 2010 ID7 Ltd.
 *
 *  Forward port and refactoring to modern qla2xxx and target/configfs
 *
 *  Copyright (C) 2010-2013 Nicholas A. Bellinger <nab@kernel.org>
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation, version 2
 *  of the License.
 *
 *  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
 *  GNU General Public License for more details.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/blkdev.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/list.h>
#include <linux/workqueue.h>
#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_tcq.h>
#include <target/target_core_base.h>
#include <target/target_core_fabric.h>

#include "qla_def.h"
#include "qla_target.h"

static int ql2xtgt_tape_enable;
module_param(ql2xtgt_tape_enable, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(ql2xtgt_tape_enable,
                "Enables Sequence level error recovery (aka FC Tape). Default is 0 - no SLER. 1 - Enable SLER.");

static char *qlini_mode = QLA2XXX_INI_MODE_STR_ENABLED;
module_param(qlini_mode, charp, S_IRUGO);
MODULE_PARM_DESC(qlini_mode,
        "Determines when initiator mode will be enabled. Possible values: "
        "\"exclusive\" - initiator mode will be enabled on load, "
        "disabled on enabling target mode and then on disabling target mode "
        "enabled back; "
        "\"disabled\" - initiator mode will never be enabled; "
        "\"enabled\" (default) - initiator mode will always stay enabled.");

int ql2x_ini_mode = QLA2XXX_INI_MODE_EXCLUSIVE;

static int temp_sam_status = SAM_STAT_BUSY;

/*
 * From scsi/fc/fc_fcp.h
 */
enum fcp_resp_rsp_codes {
        FCP_TMF_CMPL = 0,
        FCP_DATA_LEN_INVALID = 1,
        FCP_CMND_FIELDS_INVALID = 2,
        FCP_DATA_PARAM_MISMATCH = 3,
        FCP_TMF_REJECTED = 4,
        FCP_TMF_FAILED = 5,
        FCP_TMF_INVALID_LUN = 9,
};

/*
 * fc_pri_ta from scsi/fc/fc_fcp.h
 */
#define FCP_PTA_SIMPLE      0   /* simple task attribute */
#define FCP_PTA_HEADQ       1   /* head of queue task attribute */
#define FCP_PTA_ORDERED     2   /* ordered task attribute */
#define FCP_PTA_ACA         4   /* auto. contingent allegiance */
#define FCP_PTA_MASK        7   /* mask for task attribute field */
#define FCP_PRI_SHIFT       3   /* priority field starts in bit 3 */
#define FCP_PRI_RESVD_MASK  0x80        /* reserved bits in priority field */

/*
 * This driver calls qla2x00_alloc_iocbs() and qla2x00_issue_marker(), which
 * must be called under HW lock and could unlock/lock it inside.
 * It isn't an issue, since in the current implementation on the time when
 * those functions are called:
 *
 *   - Either context is IRQ and only IRQ handler can modify HW data,
 *     including rings related fields,
 *
 *   - Or access to target mode variables from struct qla_tgt doesn't
 *     cross those functions boundaries, except tgt_stop, which
 *     additionally protected by irq_cmd_count.
 */
/* Predefs for callbacks handed to qla2xxx LLD */
static void qlt_24xx_atio_pkt(struct scsi_qla_host *ha,
        struct atio_from_isp *pkt, uint8_t);
static void qlt_response_pkt(struct scsi_qla_host *ha, response_t *pkt);
static int qlt_issue_task_mgmt(struct qla_tgt_sess *sess, uint32_t lun,
        int fn, void *iocb, int flags);
static void qlt_send_term_exchange(struct scsi_qla_host *ha, struct qla_tgt_cmd
        *cmd, struct atio_from_isp *atio, int ha_locked, int ul_abort);
static void qlt_reject_free_srr_imm(struct scsi_qla_host *ha,
        struct qla_tgt_srr_imm *imm, int ha_lock);
static void qlt_abort_cmd_on_host_reset(struct scsi_qla_host *vha,
        struct qla_tgt_cmd *cmd);
static void qlt_alloc_qfull_cmd(struct scsi_qla_host *vha,
        struct atio_from_isp *atio, uint16_t status, int qfull);
static void qlt_disable_vha(struct scsi_qla_host *vha);
static void qlt_clear_tgt_db(struct qla_tgt *tgt);
static void qlt_send_notify_ack(struct scsi_qla_host *vha,
        struct imm_ntfy_from_isp *ntfy,
        uint32_t add_flags, uint16_t resp_code, int resp_code_valid,
        uint16_t srr_flags, uint16_t srr_reject_code, uint8_t srr_explan);
static void qlt_send_term_imm_notif(struct scsi_qla_host *vha,
        struct imm_ntfy_from_isp *imm, int ha_locked);
/*
 * Global Variables
 */
static struct kmem_cache *qla_tgt_mgmt_cmd_cachep;
static struct kmem_cache *qla_tgt_plogi_cachep;
static mempool_t *qla_tgt_mgmt_cmd_mempool;
static struct workqueue_struct *qla_tgt_wq;
static DEFINE_MUTEX(qla_tgt_mutex);
static LIST_HEAD(qla_tgt_glist);

/* This API intentionally takes dest as a parameter, rather than returning
 * int value to avoid caller forgetting to issue wmb() after the store */
void qlt_do_generation_tick(struct scsi_qla_host *vha, int *dest)
{
        scsi_qla_host_t *base_vha = pci_get_drvdata(vha->hw->pdev);
        *dest = atomic_inc_return(&base_vha->generation_tick);
        /* memory barrier */
        wmb();
}

/* ha->hardware_lock supposed to be held on entry (to protect tgt->sess_list) */
static struct qla_tgt_sess *qlt_find_sess_by_port_name(
        struct qla_tgt *tgt,
        const uint8_t *port_name)
{
        struct qla_tgt_sess *sess;

        list_for_each_entry(sess, &tgt->sess_list, sess_list_entry) {
                if (!memcmp(sess->port_name, port_name, WWN_SIZE))
                        return sess;
        }

        return NULL;
}

/* Might release hw lock, then reaquire!! */
static inline int qlt_issue_marker(struct scsi_qla_host *vha, int vha_locked)
{
        /* Send marker if required */
        if (unlikely(vha->marker_needed != 0)) {
                int rc = qla2x00_issue_marker(vha, vha_locked);
                if (rc != QLA_SUCCESS) {
                        ql_dbg(ql_dbg_tgt, vha, 0xe03d,
                            "qla_target(%d): issue_marker() failed\n",
                            vha->vp_idx);
                }
                return rc;
        }
        return QLA_SUCCESS;
}

static inline
struct scsi_qla_host *qlt_find_host_by_d_id(struct scsi_qla_host *vha,
        uint8_t *d_id)
{
        struct qla_hw_data *ha = vha->hw;
        uint8_t vp_idx;

        if ((vha->d_id.b.area != d_id[1]) || (vha->d_id.b.domain != d_id[0]))
                return NULL;

        if (vha->d_id.b.al_pa == d_id[2])
                return vha;

        BUG_ON(ha->tgt.tgt_vp_map == NULL);
        vp_idx = ha->tgt.tgt_vp_map[d_id[2]].idx;
        if (likely(test_bit(vp_idx, ha->vp_idx_map)))
                return ha->tgt.tgt_vp_map[vp_idx].vha;

        return NULL;
}

static inline
struct scsi_qla_host *qlt_find_host_by_vp_idx(struct scsi_qla_host *vha,
        uint16_t vp_idx)
{
        struct qla_hw_data *ha = vha->hw;

        if (vha->vp_idx == vp_idx)
                return vha;

        BUG_ON(ha->tgt.tgt_vp_map == NULL);
        if (likely(test_bit(vp_idx, ha->vp_idx_map)))
                return ha->tgt.tgt_vp_map[vp_idx].vha;

        return NULL;
}

static inline void qlt_incr_num_pend_cmds(struct scsi_qla_host *vha)
{
        unsigned long flags;

        spin_lock_irqsave(&vha->hw->tgt.q_full_lock, flags);

        vha->hw->tgt.num_pend_cmds++;
        if (vha->hw->tgt.num_pend_cmds > vha->hw->qla_stats.stat_max_pend_cmds)
                vha->hw->qla_stats.stat_max_pend_cmds =
                        vha->hw->tgt.num_pend_cmds;
        spin_unlock_irqrestore(&vha->hw->tgt.q_full_lock, flags);
}
static inline void qlt_decr_num_pend_cmds(struct scsi_qla_host *vha)
{
        unsigned long flags;

        spin_lock_irqsave(&vha->hw->tgt.q_full_lock, flags);
        vha->hw->tgt.num_pend_cmds--;
        spin_unlock_irqrestore(&vha->hw->tgt.q_full_lock, flags);
}

static bool qlt_24xx_atio_pkt_all_vps(struct scsi_qla_host *vha,
        struct atio_from_isp *atio, uint8_t ha_locked)
{
        ql_dbg(ql_dbg_tgt, vha, 0xe072,
                "%s: qla_target(%d): type %x ox_id %04x\n",
                __func__, vha->vp_idx, atio->u.raw.entry_type,
                be16_to_cpu(atio->u.isp24.fcp_hdr.ox_id));

        switch (atio->u.raw.entry_type) {
        case ATIO_TYPE7:
        {
                struct scsi_qla_host *host = qlt_find_host_by_d_id(vha,
                    atio->u.isp24.fcp_hdr.d_id);
                if (unlikely(NULL == host)) {
                        ql_dbg(ql_dbg_tgt, vha, 0xe03e,
                            "qla_target(%d): Received ATIO_TYPE7 "
                            "with unknown d_id %x:%x:%x\n", vha->vp_idx,
                            atio->u.isp24.fcp_hdr.d_id[0],
                            atio->u.isp24.fcp_hdr.d_id[1],
                            atio->u.isp24.fcp_hdr.d_id[2]);
                        break;
                }
                qlt_24xx_atio_pkt(host, atio, ha_locked);
                break;
        }

        case IMMED_NOTIFY_TYPE:
        {
                struct scsi_qla_host *host = vha;
                struct imm_ntfy_from_isp *entry =
                    (struct imm_ntfy_from_isp *)atio;

                if ((entry->u.isp24.vp_index != 0xFF) &&
                    (entry->u.isp24.nport_handle != 0xFFFF)) {
                        host = qlt_find_host_by_vp_idx(vha,
                            entry->u.isp24.vp_index);
                        if (unlikely(!host)) {
                                ql_dbg(ql_dbg_tgt, vha, 0xe03f,
                                    "qla_target(%d): Received "
                                    "ATIO (IMMED_NOTIFY_TYPE) "
                                    "with unknown vp_index %d\n",
                                    vha->vp_idx, entry->u.isp24.vp_index);
                                break;
                        }
                }
                qlt_24xx_atio_pkt(host, atio, ha_locked);
                break;
        }

        default:
                ql_dbg(ql_dbg_tgt, vha, 0xe040,
                    "qla_target(%d): Received unknown ATIO atio "
                    "type %x\n", vha->vp_idx, atio->u.raw.entry_type);
                break;
        }

        return false;
}

void qlt_response_pkt_all_vps(struct scsi_qla_host *vha, response_t *pkt)
{
        switch (pkt->entry_type) {
        case CTIO_CRC2:
                ql_dbg(ql_dbg_tgt, vha, 0xe073,
                        "qla_target(%d):%s: CRC2 Response pkt\n",
                        vha->vp_idx, __func__);
        case CTIO_TYPE7:
        {
                struct ctio7_from_24xx *entry = (struct ctio7_from_24xx *)pkt;
                struct scsi_qla_host *host = qlt_find_host_by_vp_idx(vha,
                    entry->vp_index);
                if (unlikely(!host)) {
                        ql_dbg(ql_dbg_tgt, vha, 0xe041,
                            "qla_target(%d): Response pkt (CTIO_TYPE7) "
                            "received, with unknown vp_index %d\n",
                            vha->vp_idx, entry->vp_index);
                        break;
                }
                qlt_response_pkt(host, pkt);
                break;
        }

        case IMMED_NOTIFY_TYPE:
        {
                struct scsi_qla_host *host = vha;
                struct imm_ntfy_from_isp *entry =
                    (struct imm_ntfy_from_isp *)pkt;

                host = qlt_find_host_by_vp_idx(vha, entry->u.isp24.vp_index);
                if (unlikely(!host)) {
                        ql_dbg(ql_dbg_tgt, vha, 0xe042,
                            "qla_target(%d): Response pkt (IMMED_NOTIFY_TYPE) "
                            "received, with unknown vp_index %d\n",
                            vha->vp_idx, entry->u.isp24.vp_index);
                        break;
                }
                qlt_response_pkt(host, pkt);
                break;
        }

        case NOTIFY_ACK_TYPE:
        {
                struct scsi_qla_host *host = vha;
                struct nack_to_isp *entry = (struct nack_to_isp *)pkt;

                if (0xFF != entry->u.isp24.vp_index) {
                        host = qlt_find_host_by_vp_idx(vha,
                            entry->u.isp24.vp_index);
                        if (unlikely(!host)) {
                                ql_dbg(ql_dbg_tgt, vha, 0xe043,
                                    "qla_target(%d): Response "
                                    "pkt (NOTIFY_ACK_TYPE) "
                                    "received, with unknown "
                                    "vp_index %d\n", vha->vp_idx,
                                    entry->u.isp24.vp_index);
                                break;
                        }
                }
                qlt_response_pkt(host, pkt);
                break;
        }

        case ABTS_RECV_24XX:
        {
                struct abts_recv_from_24xx *entry =
                    (struct abts_recv_from_24xx *)pkt;
                struct scsi_qla_host *host = qlt_find_host_by_vp_idx(vha,
                    entry->vp_index);
                if (unlikely(!host)) {
                        ql_dbg(ql_dbg_tgt, vha, 0xe044,
                            "qla_target(%d): Response pkt "
                            "(ABTS_RECV_24XX) received, with unknown "
                            "vp_index %d\n", vha->vp_idx, entry->vp_index);
                        break;
                }
                qlt_response_pkt(host, pkt);
                break;
        }

        case ABTS_RESP_24XX:
        {
                struct abts_resp_to_24xx *entry =
                    (struct abts_resp_to_24xx *)pkt;
                struct scsi_qla_host *host = qlt_find_host_by_vp_idx(vha,
                    entry->vp_index);
                if (unlikely(!host)) {
                        ql_dbg(ql_dbg_tgt, vha, 0xe045,
                            "qla_target(%d): Response pkt "
                            "(ABTS_RECV_24XX) received, with unknown "
                            "vp_index %d\n", vha->vp_idx, entry->vp_index);
                        break;
                }
                qlt_response_pkt(host, pkt);
                break;
        }

        default:
                qlt_response_pkt(vha, pkt);
                break;
        }

}

/*
 * All qlt_plogi_ack_t operations are protected by hardware_lock
 */

/*
 * This is a zero-base ref-counting solution, since hardware_lock
 * guarantees that ref_count is not modified concurrently.
 * Upon successful return content of iocb is undefined
 */
static qlt_plogi_ack_t *
qlt_plogi_ack_find_add(struct scsi_qla_host *vha, port_id_t *id,
                       struct imm_ntfy_from_isp *iocb)
{
        qlt_plogi_ack_t *pla;

        list_for_each_entry(pla, &vha->plogi_ack_list, list) {
                if (pla->id.b24 == id->b24) {
                        qlt_send_term_imm_notif(vha, &pla->iocb, 1);
                        pla->iocb = *iocb;
                        return pla;
                }
        }

        pla = kmem_cache_zalloc(qla_tgt_plogi_cachep, GFP_ATOMIC);
        if (!pla) {
                ql_dbg(ql_dbg_async, vha, 0x5088,
                       "qla_target(%d): Allocation of plogi_ack failed\n",
                       vha->vp_idx);
                return NULL;
        }

        pla->iocb = *iocb;
        pla->id = *id;
        list_add_tail(&pla->list, &vha->plogi_ack_list);

        return pla;
}

static void qlt_plogi_ack_unref(struct scsi_qla_host *vha, qlt_plogi_ack_t *pla)
{
        BUG_ON(!pla->ref_count);
        pla->ref_count--;

        if (pla->ref_count)
                return;

        ql_dbg(ql_dbg_async, vha, 0x5089,
            "Sending PLOGI ACK to wwn %8phC s_id %02x:%02x:%02x loop_id %#04x"
            " exch %#x ox_id %#x\n", pla->iocb.u.isp24.port_name,
            pla->iocb.u.isp24.port_id[2], pla->iocb.u.isp24.port_id[1],
            pla->iocb.u.isp24.port_id[0],
            le16_to_cpu(pla->iocb.u.isp24.nport_handle),
            pla->iocb.u.isp24.exchange_address, pla->iocb.ox_id);
        qlt_send_notify_ack(vha, &pla->iocb, 0, 0, 0, 0, 0, 0);

        list_del(&pla->list);
        kmem_cache_free(qla_tgt_plogi_cachep, pla);
}

static void
qlt_plogi_ack_link(struct scsi_qla_host *vha, qlt_plogi_ack_t *pla,
    struct qla_tgt_sess *sess, qlt_plogi_link_t link)
{
        /* Inc ref_count first because link might already be pointing at pla */
        pla->ref_count++;

        if (sess->plogi_link[link])
                qlt_plogi_ack_unref(vha, sess->plogi_link[link]);

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf097,
            "Linking sess %p [%d] wwn %8phC with PLOGI ACK to wwn %8phC"
            " s_id %02x:%02x:%02x, ref=%d\n", sess, link, sess->port_name,
            pla->iocb.u.isp24.port_name, pla->iocb.u.isp24.port_id[2],
            pla->iocb.u.isp24.port_id[1], pla->iocb.u.isp24.port_id[0],
            pla->ref_count);

        sess->plogi_link[link] = pla;
}

typedef struct {
        /* These fields must be initialized by the caller */
        port_id_t id;
        /*
         * number of cmds dropped while we were waiting for
         * initiator to ack LOGO initialize to 1 if LOGO is
         * triggered by a command, otherwise, to 0
         */
        int cmd_count;

        /* These fields are used by callee */
        struct list_head list;
} qlt_port_logo_t;

static void
qlt_send_first_logo(struct scsi_qla_host *vha, qlt_port_logo_t *logo)
{
        qlt_port_logo_t *tmp;
        int res;

        mutex_lock(&vha->vha_tgt.tgt_mutex);

        list_for_each_entry(tmp, &vha->logo_list, list) {
                if (tmp->id.b24 == logo->id.b24) {
                        tmp->cmd_count += logo->cmd_count;
                        mutex_unlock(&vha->vha_tgt.tgt_mutex);
                        return;
                }
        }

        list_add_tail(&logo->list, &vha->logo_list);

        mutex_unlock(&vha->vha_tgt.tgt_mutex);

        res = qla24xx_els_dcmd_iocb(vha, ELS_DCMD_LOGO, logo->id);

        mutex_lock(&vha->vha_tgt.tgt_mutex);
        list_del(&logo->list);
        mutex_unlock(&vha->vha_tgt.tgt_mutex);

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf098,
            "Finished LOGO to %02x:%02x:%02x, dropped %d cmds, res = %#x\n",
            logo->id.b.domain, logo->id.b.area, logo->id.b.al_pa,
            logo->cmd_count, res);
}

static void qlt_free_session_done(struct work_struct *work)
{
        struct qla_tgt_sess *sess = container_of(work, struct qla_tgt_sess,
            free_work);
        struct qla_tgt *tgt = sess->tgt;
        struct scsi_qla_host *vha = sess->vha;
        struct qla_hw_data *ha = vha->hw;
        unsigned long flags;
        bool logout_started = false;
        fc_port_t fcport;

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf084,
                "%s: se_sess %p / sess %p from port %8phC loop_id %#04x"
                " s_id %02x:%02x:%02x logout %d keep %d els_logo %d\n",
                __func__, sess->se_sess, sess, sess->port_name, sess->loop_id,
                sess->s_id.b.domain, sess->s_id.b.area, sess->s_id.b.al_pa,
                sess->logout_on_delete, sess->keep_nport_handle,
                sess->send_els_logo);

        BUG_ON(!tgt);

        if (sess->send_els_logo) {
                qlt_port_logo_t logo;
                logo.id = sess->s_id;
                logo.cmd_count = 0;
                qlt_send_first_logo(vha, &logo);
        }

        if (sess->logout_on_delete) {
                int rc;

                memset(&fcport, 0, sizeof(fcport));
                fcport.loop_id = sess->loop_id;
                fcport.d_id = sess->s_id;
                memcpy(fcport.port_name, sess->port_name, WWN_SIZE);
                fcport.vha = vha;
                fcport.tgt_session = sess;

                rc = qla2x00_post_async_logout_work(vha, &fcport, NULL);
                if (rc != QLA_SUCCESS)
                        ql_log(ql_log_warn, vha, 0xf085,
                               "Schedule logo failed sess %p rc %d\n",
                               sess, rc);
                else
                        logout_started = true;
        }

        /*
         * Release the target session for FC Nexus from fabric module code.
         */
        if (sess->se_sess != NULL)
                ha->tgt.tgt_ops->free_session(sess);

        if (logout_started) {
                bool traced = false;

                while (!ACCESS_ONCE(sess->logout_completed)) {
                        if (!traced) {
                                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf086,
                                        "%s: waiting for sess %p logout\n",
                                        __func__, sess);
                                traced = true;
                        }
                        msleep(100);
                }

                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf087,
                        "%s: sess %p logout completed\n",
                        __func__, sess);
        }

        spin_lock_irqsave(&ha->hardware_lock, flags);

        {
                qlt_plogi_ack_t *own =
                    sess->plogi_link[QLT_PLOGI_LINK_SAME_WWN];
                qlt_plogi_ack_t *con =
                    sess->plogi_link[QLT_PLOGI_LINK_CONFLICT];

                if (con) {
                        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf099,
                            "se_sess %p / sess %p port %8phC is gone,"
                            " %s (ref=%d), releasing PLOGI for %8phC (ref=%d)\n",
                            sess->se_sess, sess, sess->port_name,
                            own ? "releasing own PLOGI" :
                            "no own PLOGI pending",
                            own ? own->ref_count : -1,
                            con->iocb.u.isp24.port_name, con->ref_count);
                        qlt_plogi_ack_unref(vha, con);
                } else {
                        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf09a,
                            "se_sess %p / sess %p port %8phC is gone, %s (ref=%d)\n",
                            sess->se_sess, sess, sess->port_name,
                            own ? "releasing own PLOGI" :
                            "no own PLOGI pending",
                            own ? own->ref_count : -1);
                }

                if (own)
                        qlt_plogi_ack_unref(vha, own);
        }

        list_del(&sess->sess_list_entry);

        spin_unlock_irqrestore(&ha->hardware_lock, flags);

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf001,
            "Unregistration of sess %p finished\n", sess);

        kfree(sess);
        /*
         * We need to protect against race, when tgt is freed before or
         * inside wake_up()
         */
        tgt->sess_count--;
        if (tgt->sess_count == 0)
                wake_up_all(&tgt->waitQ);
}

/* ha->tgt.sess_lock supposed to be held on entry */
void qlt_unreg_sess(struct qla_tgt_sess *sess)
{
        struct scsi_qla_host *vha = sess->vha;

        if (sess->se_sess)
                vha->hw->tgt.tgt_ops->clear_nacl_from_fcport_map(sess);

        if (!list_empty(&sess->del_list_entry))
                list_del_init(&sess->del_list_entry);
        sess->deleted = QLA_SESS_DELETION_IN_PROGRESS;

        INIT_WORK(&sess->free_work, qlt_free_session_done);
        schedule_work(&sess->free_work);
}
EXPORT_SYMBOL(qlt_unreg_sess);


static int qlt_reset(struct scsi_qla_host *vha, void *iocb, int mcmd)
{
        struct qla_hw_data *ha = vha->hw;
        struct qla_tgt_sess *sess = NULL;
        uint32_t unpacked_lun, lun = 0;
        uint16_t loop_id;
        int res = 0;
        struct imm_ntfy_from_isp *n = (struct imm_ntfy_from_isp *)iocb;
        struct atio_from_isp *a = (struct atio_from_isp *)iocb;
        unsigned long flags;

        loop_id = le16_to_cpu(n->u.isp24.nport_handle);
        if (loop_id == 0xFFFF) {
                /* Global event */
                atomic_inc(&vha->vha_tgt.qla_tgt->tgt_global_resets_count);
                spin_lock_irqsave(&ha->tgt.sess_lock, flags);
                qlt_clear_tgt_db(vha->vha_tgt.qla_tgt);
                spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
#if 0 /* FIXME: do we need to choose a session here? */
                if (!list_empty(&ha->tgt.qla_tgt->sess_list)) {
                        sess = list_entry(ha->tgt.qla_tgt->sess_list.next,
                            typeof(*sess), sess_list_entry);
                        switch (mcmd) {
                        case QLA_TGT_NEXUS_LOSS_SESS:
                                mcmd = QLA_TGT_NEXUS_LOSS;
                                break;
                        case QLA_TGT_ABORT_ALL_SESS:
                                mcmd = QLA_TGT_ABORT_ALL;
                                break;
                        case QLA_TGT_NEXUS_LOSS:
                        case QLA_TGT_ABORT_ALL:
                                break;
                        default:
                                ql_dbg(ql_dbg_tgt, vha, 0xe046,
                                    "qla_target(%d): Not allowed "
                                    "command %x in %s", vha->vp_idx,
                                    mcmd, __func__);
                                sess = NULL;
                                break;
                        }
                } else
                        sess = NULL;
#endif
        } else {
                spin_lock_irqsave(&ha->tgt.sess_lock, flags);
                sess = ha->tgt.tgt_ops->find_sess_by_loop_id(vha, loop_id);
                spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
        }

        ql_dbg(ql_dbg_tgt, vha, 0xe000,
            "Using sess for qla_tgt_reset: %p\n", sess);
        if (!sess) {
                res = -ESRCH;
                return res;
        }

        ql_dbg(ql_dbg_tgt, vha, 0xe047,
            "scsi(%ld): resetting (session %p from port %8phC mcmd %x, "
            "loop_id %d)\n", vha->host_no, sess, sess->port_name,
            mcmd, loop_id);

        lun = a->u.isp24.fcp_cmnd.lun;
        unpacked_lun = scsilun_to_int((struct scsi_lun *)&lun);

        return qlt_issue_task_mgmt(sess, unpacked_lun, mcmd,
            iocb, QLA24XX_MGMT_SEND_NACK);
}

/* ha->tgt.sess_lock supposed to be held on entry */
static void qlt_schedule_sess_for_deletion(struct qla_tgt_sess *sess,
        bool immediate)
{
        struct qla_tgt *tgt = sess->tgt;
        uint32_t dev_loss_tmo = tgt->ha->port_down_retry_count + 5;

        if (sess->deleted) {
                /* Upgrade to unconditional deletion in case it was temporary */
                if (immediate && sess->deleted == QLA_SESS_DELETION_PENDING)
                        list_del(&sess->del_list_entry);
                else
                        return;
        }

        ql_dbg(ql_dbg_tgt, sess->vha, 0xe001,
            "Scheduling sess %p for deletion\n", sess);

        if (immediate) {
                dev_loss_tmo = 0;
                sess->deleted = QLA_SESS_DELETION_IN_PROGRESS;
                list_add(&sess->del_list_entry, &tgt->del_sess_list);
        } else {
                sess->deleted = QLA_SESS_DELETION_PENDING;
                list_add_tail(&sess->del_list_entry, &tgt->del_sess_list);
        }

        sess->expires = jiffies + dev_loss_tmo * HZ;

        ql_dbg(ql_dbg_tgt, sess->vha, 0xe048,
            "qla_target(%d): session for port %8phC (loop ID %d s_id %02x:%02x:%02x)"
            " scheduled for deletion in %u secs (expires: %lu) immed: %d, logout: %d, gen: %#x\n",
            sess->vha->vp_idx, sess->port_name, sess->loop_id,
            sess->s_id.b.domain, sess->s_id.b.area, sess->s_id.b.al_pa,
            dev_loss_tmo, sess->expires, immediate, sess->logout_on_delete,
            sess->generation);

        if (immediate)
                mod_delayed_work(system_wq, &tgt->sess_del_work, 0);
        else
                schedule_delayed_work(&tgt->sess_del_work,
                    sess->expires - jiffies);
}

/* ha->tgt.sess_lock supposed to be held on entry */
static void qlt_clear_tgt_db(struct qla_tgt *tgt)
{
        struct qla_tgt_sess *sess;

        list_for_each_entry(sess, &tgt->sess_list, sess_list_entry)
                qlt_schedule_sess_for_deletion(sess, true);

        /* At this point tgt could be already dead */
}

static int qla24xx_get_loop_id(struct scsi_qla_host *vha, const uint8_t *s_id,
        uint16_t *loop_id)
{
        struct qla_hw_data *ha = vha->hw;
        dma_addr_t gid_list_dma;
        struct gid_list_info *gid_list;
        char *id_iter;
        int res, rc, i;
        uint16_t entries;

        gid_list = dma_alloc_coherent(&ha->pdev->dev, qla2x00_gid_list_size(ha),
            &gid_list_dma, GFP_KERNEL);
        if (!gid_list) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf044,
                    "qla_target(%d): DMA Alloc failed of %u\n",
                    vha->vp_idx, qla2x00_gid_list_size(ha));
                return -ENOMEM;
        }

        /* Get list of logged in devices */
        rc = qla2x00_get_id_list(vha, gid_list, gid_list_dma, &entries);
        if (rc != QLA_SUCCESS) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf045,
                    "qla_target(%d): get_id_list() failed: %x\n",
                    vha->vp_idx, rc);
                res = -EBUSY;
                goto out_free_id_list;
        }

        id_iter = (char *)gid_list;
        res = -ENOENT;
        for (i = 0; i < entries; i++) {
                struct gid_list_info *gid = (struct gid_list_info *)id_iter;
                if ((gid->al_pa == s_id[2]) &&
                    (gid->area == s_id[1]) &&
                    (gid->domain == s_id[0])) {
                        *loop_id = le16_to_cpu(gid->loop_id);
                        res = 0;
                        break;
                }
                id_iter += ha->gid_list_info_size;
        }

out_free_id_list:
        dma_free_coherent(&ha->pdev->dev, qla2x00_gid_list_size(ha),
            gid_list, gid_list_dma);
        return res;
}

/* ha->tgt.sess_lock supposed to be held on entry */
static void qlt_undelete_sess(struct qla_tgt_sess *sess)
{
        BUG_ON(sess->deleted != QLA_SESS_DELETION_PENDING);

        list_del_init(&sess->del_list_entry);
        sess->deleted = 0;
}

static void qlt_del_sess_work_fn(struct delayed_work *work)
{
        struct qla_tgt *tgt = container_of(work, struct qla_tgt,
            sess_del_work);
        struct scsi_qla_host *vha = tgt->vha;
        struct qla_hw_data *ha = vha->hw;
        struct qla_tgt_sess *sess;
        unsigned long flags, elapsed;

        spin_lock_irqsave(&ha->tgt.sess_lock, flags);
        while (!list_empty(&tgt->del_sess_list)) {
                sess = list_entry(tgt->del_sess_list.next, typeof(*sess),
                    del_list_entry);
                elapsed = jiffies;
                if (time_after_eq(elapsed, sess->expires)) {
                        /* No turning back */
                        list_del_init(&sess->del_list_entry);
                        sess->deleted = QLA_SESS_DELETION_IN_PROGRESS;

                        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf004,
                            "Timeout: sess %p about to be deleted\n",
                            sess);
                        if (sess->se_sess) {
                                ha->tgt.tgt_ops->shutdown_sess(sess);
                                ha->tgt.tgt_ops->put_sess(sess);
                        } else {
                                qlt_unreg_sess(sess);
                        }
                } else {
                        schedule_delayed_work(&tgt->sess_del_work,
                            sess->expires - elapsed);
                        break;
                }
        }
        spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
}

/*
 * Adds an extra ref to allow to drop hw lock after adding sess to the list.
 * Caller must put it.
 */
static struct qla_tgt_sess *qlt_create_sess(
        struct scsi_qla_host *vha,
        fc_port_t *fcport,
        bool local)
{
        struct qla_hw_data *ha = vha->hw;
        struct qla_tgt_sess *sess;
        unsigned long flags;

        /* Check to avoid double sessions */
        spin_lock_irqsave(&ha->tgt.sess_lock, flags);
        list_for_each_entry(sess, &vha->vha_tgt.qla_tgt->sess_list,
                                sess_list_entry) {
                if (!memcmp(sess->port_name, fcport->port_name, WWN_SIZE)) {
                        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf005,
                            "Double sess %p found (s_id %x:%x:%x, "
                            "loop_id %d), updating to d_id %x:%x:%x, "
                            "loop_id %d", sess, sess->s_id.b.domain,
                            sess->s_id.b.al_pa, sess->s_id.b.area,
                            sess->loop_id, fcport->d_id.b.domain,
                            fcport->d_id.b.al_pa, fcport->d_id.b.area,
                            fcport->loop_id);

                        /* Cannot undelete at this point */
                        if (sess->deleted == QLA_SESS_DELETION_IN_PROGRESS) {
                                spin_unlock_irqrestore(&ha->tgt.sess_lock,
                                    flags);
                                return NULL;
                        }

                        if (sess->deleted)
                                qlt_undelete_sess(sess);

                        if (!sess->se_sess) {
                                if (ha->tgt.tgt_ops->check_initiator_node_acl(vha,
                                    &sess->port_name[0], sess) < 0) {
                                        spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
                                        return NULL;
                                }
                        }

                        kref_get(&sess->se_sess->sess_kref);
                        ha->tgt.tgt_ops->update_sess(sess, fcport->d_id, fcport->loop_id,
                                                (fcport->flags & FCF_CONF_COMP_SUPPORTED));

                        if (sess->local && !local)
                                sess->local = 0;

                        qlt_do_generation_tick(vha, &sess->generation);

                        spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);

                        return sess;
                }
        }
        spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);

        sess = kzalloc(sizeof(*sess), GFP_KERNEL);
        if (!sess) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf04a,
                    "qla_target(%u): session allocation failed, all commands "
                    "from port %8phC will be refused", vha->vp_idx,
                    fcport->port_name);

                return NULL;
        }
        sess->tgt = vha->vha_tgt.qla_tgt;
        sess->vha = vha;
        sess->s_id = fcport->d_id;
        sess->loop_id = fcport->loop_id;
        sess->local = local;
        INIT_LIST_HEAD(&sess->del_list_entry);

        /* Under normal circumstances we want to logout from firmware when
         * session eventually ends and release corresponding nport handle.
         * In the exception cases (e.g. when new PLOGI is waiting) corresponding
         * code will adjust these flags as necessary. */
        sess->logout_on_delete = 1;
        sess->keep_nport_handle = 0;

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf006,
            "Adding sess %p to tgt %p via ->check_initiator_node_acl()\n",
            sess, vha->vha_tgt.qla_tgt);

        sess->conf_compl_supported = (fcport->flags & FCF_CONF_COMP_SUPPORTED);
        BUILD_BUG_ON(sizeof(sess->port_name) != sizeof(fcport->port_name));
        memcpy(sess->port_name, fcport->port_name, sizeof(sess->port_name));

        spin_lock_irqsave(&ha->tgt.sess_lock, flags);
        list_add_tail(&sess->sess_list_entry, &vha->vha_tgt.qla_tgt->sess_list);
        vha->vha_tgt.qla_tgt->sess_count++;
        qlt_do_generation_tick(vha, &sess->generation);
        spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf04b,
            "qla_target(%d): %ssession for wwn %8phC (loop_id %d, "
            "s_id %x:%x:%x, confirmed completion %ssupported) added\n",
            vha->vp_idx, local ?  "local " : "", fcport->port_name,
            fcport->loop_id, sess->s_id.b.domain, sess->s_id.b.area,
            sess->s_id.b.al_pa, sess->conf_compl_supported ?  "" : "not ");

        /*
         * Determine if this fc_port->port_name is allowed to access
         * target mode using explict NodeACLs+MappedLUNs, or using
         * TPG demo mode.  If this is successful a target mode FC nexus
         * is created.
         */
        if (ha->tgt.tgt_ops->check_initiator_node_acl(vha,
            &fcport->port_name[0], sess) < 0) {
                return NULL;
        } else {
                /*
                 * Take an extra reference to ->sess_kref here to handle qla_tgt_sess
                 * access across ->tgt.sess_lock reaquire.
                 */
                kref_get(&sess->se_sess->sess_kref);
        }

        return sess;
}

/*

 * Called from qla2x00_reg_remote_port()
 */
void qlt_fc_port_added(struct scsi_qla_host *vha, fc_port_t *fcport)
{
        struct qla_hw_data *ha = vha->hw;
        struct qla_tgt *tgt = vha->vha_tgt.qla_tgt;
        struct qla_tgt_sess *sess;
        unsigned long flags;

        if (!vha->hw->tgt.tgt_ops)
                return;

        if (!tgt || (fcport->port_type != FCT_INITIATOR))
                return;

        if (qla_ini_mode_enabled(vha))
                return;

        spin_lock_irqsave(&ha->tgt.sess_lock, flags);
        if (tgt->tgt_stop) {
                spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
                return;
        }
        sess = qlt_find_sess_by_port_name(tgt, fcport->port_name);
        if (!sess) {
                spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);

                mutex_lock(&vha->vha_tgt.tgt_mutex);
                sess = qlt_create_sess(vha, fcport, false);
                mutex_unlock(&vha->vha_tgt.tgt_mutex);

                spin_lock_irqsave(&ha->tgt.sess_lock, flags);
        } else if (sess->deleted == QLA_SESS_DELETION_IN_PROGRESS) {
                /* Point of no return */
                spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
                return;
        } else {
                kref_get(&sess->se_sess->sess_kref);

                if (sess->deleted) {
                        qlt_undelete_sess(sess);

                        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf04c,
                            "qla_target(%u): %ssession for port %8phC "
                            "(loop ID %d) reappeared\n", vha->vp_idx,
                            sess->local ? "local " : "", sess->port_name,
                            sess->loop_id);

                        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf007,
                            "Reappeared sess %p\n", sess);
                }
                ha->tgt.tgt_ops->update_sess(sess, fcport->d_id, fcport->loop_id,
                                        (fcport->flags & FCF_CONF_COMP_SUPPORTED));
        }

        if (sess && sess->local) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf04d,
                    "qla_target(%u): local session for "
                    "port %8phC (loop ID %d) became global\n", vha->vp_idx,
                    fcport->port_name, sess->loop_id);
                sess->local = 0;
        }
        ha->tgt.tgt_ops->put_sess(sess);
        spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
}

/*
 * max_gen - specifies maximum session generation
 * at which this deletion requestion is still valid
 */
void
qlt_fc_port_deleted(struct scsi_qla_host *vha, fc_port_t *fcport, int max_gen)
{
        struct qla_tgt *tgt = vha->vha_tgt.qla_tgt;
        struct qla_tgt_sess *sess;
        unsigned long flags;

        if (!vha->hw->tgt.tgt_ops)
                return;

        if (!tgt)
                return;

        spin_lock_irqsave(&vha->hw->tgt.sess_lock, flags);
        if (tgt->tgt_stop) {
                spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
                return;
        }
        sess = qlt_find_sess_by_port_name(tgt, fcport->port_name);
        if (!sess) {
                spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
                return;
        }

        if (max_gen - sess->generation < 0) {
                spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf092,
                    "Ignoring stale deletion request for se_sess %p / sess %p"
                    " for port %8phC, req_gen %d, sess_gen %d\n",
                    sess->se_sess, sess, sess->port_name, max_gen,
                    sess->generation);
                return;
        }

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf008, "qla_tgt_fc_port_deleted %p", sess);

        sess->local = 1;
        qlt_schedule_sess_for_deletion(sess, false);
        spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
}

static inline int test_tgt_sess_count(struct qla_tgt *tgt)
{
        struct qla_hw_data *ha = tgt->ha;
        unsigned long flags;
        int res;
        /*
         * We need to protect against race, when tgt is freed before or
         * inside wake_up()
         */
        spin_lock_irqsave(&ha->hardware_lock, flags);
        ql_dbg(ql_dbg_tgt, tgt->vha, 0xe002,
            "tgt %p, empty(sess_list)=%d sess_count=%d\n",
            tgt, list_empty(&tgt->sess_list), tgt->sess_count);
        res = (tgt->sess_count == 0);
        spin_unlock_irqrestore(&ha->hardware_lock, flags);

        return res;
}

/* Called by tcm_qla2xxx configfs code */
int qlt_stop_phase1(struct qla_tgt *tgt)
{
        struct scsi_qla_host *vha = tgt->vha;
        struct qla_hw_data *ha = tgt->ha;
        unsigned long flags;

        mutex_lock(&qla_tgt_mutex);
        if (!vha->fc_vport) {
                struct Scsi_Host *sh = vha->host;
                struct fc_host_attrs *fc_host = shost_to_fc_host(sh);
                bool npiv_vports;

                spin_lock_irqsave(sh->host_lock, flags);
                npiv_vports = (fc_host->npiv_vports_inuse);
                spin_unlock_irqrestore(sh->host_lock, flags);

                if (npiv_vports) {
                        mutex_unlock(&qla_tgt_mutex);
                        return -EPERM;
                }
        }
        if (tgt->tgt_stop || tgt->tgt_stopped) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf04e,
                    "Already in tgt->tgt_stop or tgt_stopped state\n");
                mutex_unlock(&qla_tgt_mutex);
                return -EPERM;
        }

        ql_dbg(ql_dbg_tgt, vha, 0xe003, "Stopping target for host %ld(%p)\n",
            vha->host_no, vha);
        /*
         * Mutex needed to sync with qla_tgt_fc_port_[added,deleted].
         * Lock is needed, because we still can get an incoming packet.
         */
        mutex_lock(&vha->vha_tgt.tgt_mutex);
        spin_lock_irqsave(&ha->tgt.sess_lock, flags);
        tgt->tgt_stop = 1;
        qlt_clear_tgt_db(tgt);
        spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
        mutex_unlock(&vha->vha_tgt.tgt_mutex);
        mutex_unlock(&qla_tgt_mutex);

        flush_delayed_work(&tgt->sess_del_work);

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf009,
            "Waiting for sess works (tgt %p)", tgt);
        spin_lock_irqsave(&tgt->sess_work_lock, flags);
        while (!list_empty(&tgt->sess_works_list)) {
                spin_unlock_irqrestore(&tgt->sess_work_lock, flags);
                flush_scheduled_work();
                spin_lock_irqsave(&tgt->sess_work_lock, flags);
        }
        spin_unlock_irqrestore(&tgt->sess_work_lock, flags);

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf00a,
            "Waiting for tgt %p: list_empty(sess_list)=%d "
            "sess_count=%d\n", tgt, list_empty(&tgt->sess_list),
            tgt->sess_count);

        wait_event(tgt->waitQ, test_tgt_sess_count(tgt));

        /* Big hammer */
        if (!ha->flags.host_shutting_down && qla_tgt_mode_enabled(vha))
                qlt_disable_vha(vha);

        /* Wait for sessions to clear out (just in case) */
        wait_event(tgt->waitQ, test_tgt_sess_count(tgt));
        return 0;
}
EXPORT_SYMBOL(qlt_stop_phase1);

/* Called by tcm_qla2xxx configfs code */
void qlt_stop_phase2(struct qla_tgt *tgt)
{
        struct qla_hw_data *ha = tgt->ha;
        scsi_qla_host_t *vha = pci_get_drvdata(ha->pdev);
        unsigned long flags;

        if (tgt->tgt_stopped) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf04f,
                    "Already in tgt->tgt_stopped state\n");
                dump_stack();
                return;
        }

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf00b,
            "Waiting for %d IRQ commands to complete (tgt %p)",
            tgt->irq_cmd_count, tgt);

        mutex_lock(&vha->vha_tgt.tgt_mutex);
        spin_lock_irqsave(&ha->hardware_lock, flags);
        while ((tgt->irq_cmd_count != 0) || (tgt->atio_irq_cmd_count != 0)) {
                spin_unlock_irqrestore(&ha->hardware_lock, flags);
                udelay(2);
                spin_lock_irqsave(&ha->hardware_lock, flags);
        }
        tgt->tgt_stop = 0;
        tgt->tgt_stopped = 1;
        spin_unlock_irqrestore(&ha->hardware_lock, flags);
        mutex_unlock(&vha->vha_tgt.tgt_mutex);

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf00c, "Stop of tgt %p finished",
            tgt);
}
EXPORT_SYMBOL(qlt_stop_phase2);

/* Called from qlt_remove_target() -> qla2x00_remove_one() */
static void qlt_release(struct qla_tgt *tgt)
{
        scsi_qla_host_t *vha = tgt->vha;

        if ((vha->vha_tgt.qla_tgt != NULL) && !tgt->tgt_stopped)
                qlt_stop_phase2(tgt);

        vha->vha_tgt.qla_tgt = NULL;

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf00d,
            "Release of tgt %p finished\n", tgt);

        kfree(tgt);
}

/* ha->hardware_lock supposed to be held on entry */
static int qlt_sched_sess_work(struct qla_tgt *tgt, int type,
        const void *param, unsigned int param_size)
{
        struct qla_tgt_sess_work_param *prm;
        unsigned long flags;

        prm = kzalloc(sizeof(*prm), GFP_ATOMIC);
        if (!prm) {
                ql_dbg(ql_dbg_tgt_mgt, tgt->vha, 0xf050,
                    "qla_target(%d): Unable to create session "
                    "work, command will be refused", 0);
                return -ENOMEM;
        }

        ql_dbg(ql_dbg_tgt_mgt, tgt->vha, 0xf00e,
            "Scheduling work (type %d, prm %p)"
            " to find session for param %p (size %d, tgt %p)\n",
            type, prm, param, param_size, tgt);

        prm->type = type;
        memcpy(&prm->tm_iocb, param, param_size);

        spin_lock_irqsave(&tgt->sess_work_lock, flags);
        list_add_tail(&prm->sess_works_list_entry, &tgt->sess_works_list);
        spin_unlock_irqrestore(&tgt->sess_work_lock, flags);

        schedule_work(&tgt->sess_work);

        return 0;
}

/*
 * ha->hardware_lock supposed to be held on entry. Might drop it, then reaquire
 */
static void qlt_send_notify_ack(struct scsi_qla_host *vha,
        struct imm_ntfy_from_isp *ntfy,
        uint32_t add_flags, uint16_t resp_code, int resp_code_valid,
        uint16_t srr_flags, uint16_t srr_reject_code, uint8_t srr_explan)
{
        struct qla_hw_data *ha = vha->hw;
        request_t *pkt;
        struct nack_to_isp *nack;

        ql_dbg(ql_dbg_tgt, vha, 0xe004, "Sending NOTIFY_ACK (ha=%p)\n", ha);

        /* Send marker if required */
        if (qlt_issue_marker(vha, 1) != QLA_SUCCESS)
                return;

        pkt = (request_t *)qla2x00_alloc_iocbs(vha, NULL);
        if (!pkt) {
                ql_dbg(ql_dbg_tgt, vha, 0xe049,
                    "qla_target(%d): %s failed: unable to allocate "
                    "request packet\n", vha->vp_idx, __func__);
                return;
        }

        if (vha->vha_tgt.qla_tgt != NULL)
                vha->vha_tgt.qla_tgt->notify_ack_expected++;

        pkt->entry_type = NOTIFY_ACK_TYPE;
        pkt->entry_count = 1;

        nack = (struct nack_to_isp *)pkt;
        nack->ox_id = ntfy->ox_id;

        nack->u.isp24.nport_handle = ntfy->u.isp24.nport_handle;
        if (le16_to_cpu(ntfy->u.isp24.status) == IMM_NTFY_ELS) {
                nack->u.isp24.flags = ntfy->u.isp24.flags &
                        cpu_to_le32(NOTIFY24XX_FLAGS_PUREX_IOCB);
        }
        nack->u.isp24.srr_rx_id = ntfy->u.isp24.srr_rx_id;
        nack->u.isp24.status = ntfy->u.isp24.status;
        nack->u.isp24.status_subcode = ntfy->u.isp24.status_subcode;
        nack->u.isp24.fw_handle = ntfy->u.isp24.fw_handle;
        nack->u.isp24.exchange_address = ntfy->u.isp24.exchange_address;
        nack->u.isp24.srr_rel_offs = ntfy->u.isp24.srr_rel_offs;
        nack->u.isp24.srr_ui = ntfy->u.isp24.srr_ui;
        nack->u.isp24.srr_flags = cpu_to_le16(srr_flags);
        nack->u.isp24.srr_reject_code = srr_reject_code;
        nack->u.isp24.srr_reject_code_expl = srr_explan;
        nack->u.isp24.vp_index = ntfy->u.isp24.vp_index;

        ql_dbg(ql_dbg_tgt, vha, 0xe005,
            "qla_target(%d): Sending 24xx Notify Ack %d\n",
            vha->vp_idx, nack->u.isp24.status);

        /* Memory Barrier */
        wmb();
        qla2x00_start_iocbs(vha, vha->req);
}

/*
 * ha->hardware_lock supposed to be held on entry. Might drop it, then reaquire
 */
static void qlt_24xx_send_abts_resp(struct scsi_qla_host *vha,
        struct abts_recv_from_24xx *abts, uint32_t status,
        bool ids_reversed)
{
        struct qla_hw_data *ha = vha->hw;
        struct abts_resp_to_24xx *resp;
        uint32_t f_ctl;
        uint8_t *p;

        ql_dbg(ql_dbg_tgt, vha, 0xe006,
            "Sending task mgmt ABTS response (ha=%p, atio=%p, status=%x\n",
            ha, abts, status);

        /* Send marker if required */
        if (qlt_issue_marker(vha, 1) != QLA_SUCCESS)
                return;

        resp = (struct abts_resp_to_24xx *)qla2x00_alloc_iocbs_ready(vha, NULL);
        if (!resp) {
                ql_dbg(ql_dbg_tgt, vha, 0xe04a,
                    "qla_target(%d): %s failed: unable to allocate "
                    "request packet", vha->vp_idx, __func__);
                return;
        }

        resp->entry_type = ABTS_RESP_24XX;
        resp->entry_count = 1;
        resp->nport_handle = abts->nport_handle;
        resp->vp_index = vha->vp_idx;
        resp->sof_type = abts->sof_type;
        resp->exchange_address = abts->exchange_address;
        resp->fcp_hdr_le = abts->fcp_hdr_le;
        f_ctl = cpu_to_le32(F_CTL_EXCH_CONTEXT_RESP |
            F_CTL_LAST_SEQ | F_CTL_END_SEQ |
            F_CTL_SEQ_INITIATIVE);
        p = (uint8_t *)&f_ctl;
        resp->fcp_hdr_le.f_ctl[0] = *p++;
        resp->fcp_hdr_le.f_ctl[1] = *p++;
        resp->fcp_hdr_le.f_ctl[2] = *p;
        if (ids_reversed) {
                resp->fcp_hdr_le.d_id[0] = abts->fcp_hdr_le.d_id[0];
                resp->fcp_hdr_le.d_id[1] = abts->fcp_hdr_le.d_id[1];
                resp->fcp_hdr_le.d_id[2] = abts->fcp_hdr_le.d_id[2];
                resp->fcp_hdr_le.s_id[0] = abts->fcp_hdr_le.s_id[0];
                resp->fcp_hdr_le.s_id[1] = abts->fcp_hdr_le.s_id[1];
                resp->fcp_hdr_le.s_id[2] = abts->fcp_hdr_le.s_id[2];
        } else {
                resp->fcp_hdr_le.d_id[0] = abts->fcp_hdr_le.s_id[0];
                resp->fcp_hdr_le.d_id[1] = abts->fcp_hdr_le.s_id[1];
                resp->fcp_hdr_le.d_id[2] = abts->fcp_hdr_le.s_id[2];
                resp->fcp_hdr_le.s_id[0] = abts->fcp_hdr_le.d_id[0];
                resp->fcp_hdr_le.s_id[1] = abts->fcp_hdr_le.d_id[1];
                resp->fcp_hdr_le.s_id[2] = abts->fcp_hdr_le.d_id[2];
        }
        resp->exchange_addr_to_abort = abts->exchange_addr_to_abort;
        if (status == FCP_TMF_CMPL) {
                resp->fcp_hdr_le.r_ctl = R_CTL_BASIC_LINK_SERV | R_CTL_B_ACC;
                resp->payload.ba_acct.seq_id_valid = SEQ_ID_INVALID;
                resp->payload.ba_acct.low_seq_cnt = 0x0000;
                resp->payload.ba_acct.high_seq_cnt = 0xFFFF;
                resp->payload.ba_acct.ox_id = abts->fcp_hdr_le.ox_id;
                resp->payload.ba_acct.rx_id = abts->fcp_hdr_le.rx_id;
        } else {
                resp->fcp_hdr_le.r_ctl = R_CTL_BASIC_LINK_SERV | R_CTL_B_RJT;
                resp->payload.ba_rjt.reason_code =
                        BA_RJT_REASON_CODE_UNABLE_TO_PERFORM;
                /* Other bytes are zero */
        }

        vha->vha_tgt.qla_tgt->abts_resp_expected++;

        /* Memory Barrier */
        wmb();
        qla2x00_start_iocbs(vha, vha->req);
}

/*
 * ha->hardware_lock supposed to be held on entry. Might drop it, then reaquire
 */
static void qlt_24xx_retry_term_exchange(struct scsi_qla_host *vha,
        struct abts_resp_from_24xx_fw *entry)
{
        struct ctio7_to_24xx *ctio;

        ql_dbg(ql_dbg_tgt, vha, 0xe007,
            "Sending retry TERM EXCH CTIO7 (ha=%p)\n", vha->hw);
        /* Send marker if required */
        if (qlt_issue_marker(vha, 1) != QLA_SUCCESS)
                return;

        ctio = (struct ctio7_to_24xx *)qla2x00_alloc_iocbs_ready(vha, NULL);
        if (ctio == NULL) {
                ql_dbg(ql_dbg_tgt, vha, 0xe04b,
                    "qla_target(%d): %s failed: unable to allocate "
                    "request packet\n", vha->vp_idx, __func__);
                return;
        }

        /*
         * We've got on entrance firmware's response on by us generated
         * ABTS response. So, in it ID fields are reversed.
         */

        ctio->entry_type = CTIO_TYPE7;
        ctio->entry_count = 1;
        ctio->nport_handle = entry->nport_handle;
        ctio->handle = QLA_TGT_SKIP_HANDLE |    CTIO_COMPLETION_HANDLE_MARK;
        ctio->timeout = cpu_to_le16(QLA_TGT_TIMEOUT);
        ctio->vp_index = vha->vp_idx;
        ctio->initiator_id[0] = entry->fcp_hdr_le.d_id[0];
        ctio->initiator_id[1] = entry->fcp_hdr_le.d_id[1];
        ctio->initiator_id[2] = entry->fcp_hdr_le.d_id[2];
        ctio->exchange_addr = entry->exchange_addr_to_abort;
        ctio->u.status1.flags = cpu_to_le16(CTIO7_FLAGS_STATUS_MODE_1 |
                                            CTIO7_FLAGS_TERMINATE);
        ctio->u.status1.ox_id = cpu_to_le16(entry->fcp_hdr_le.ox_id);

        /* Memory Barrier */
        wmb();
        qla2x00_start_iocbs(vha, vha->req);

        qlt_24xx_send_abts_resp(vha, (struct abts_recv_from_24xx *)entry,
            FCP_TMF_CMPL, true);
}

static int abort_cmd_for_tag(struct scsi_qla_host *vha, uint32_t tag)
{
        struct qla_tgt_sess_op *op;
        struct qla_tgt_cmd *cmd;

        spin_lock(&vha->cmd_list_lock);

        list_for_each_entry(op, &vha->qla_sess_op_cmd_list, cmd_list) {
                if (tag == op->atio.u.isp24.exchange_addr) {
                        op->aborted = true;
                        spin_unlock(&vha->cmd_list_lock);
                        return 1;
                }
        }

        list_for_each_entry(cmd, &vha->qla_cmd_list, cmd_list) {
                if (tag == cmd->atio.u.isp24.exchange_addr) {
                        cmd->aborted = 1;
                        spin_unlock(&vha->cmd_list_lock);
                        return 1;
                }
        }

        spin_unlock(&vha->cmd_list_lock);
        return 0;
}

/* drop cmds for the given lun
 * XXX only looks for cmds on the port through which lun reset was recieved
 * XXX does not go through the list of other port (which may have cmds
 *     for the same lun)
 */
static void abort_cmds_for_lun(struct scsi_qla_host *vha,
                                uint32_t lun, uint8_t *s_id)
{
        struct qla_tgt_sess_op *op;
        struct qla_tgt_cmd *cmd;
        uint32_t key;

        key = sid_to_key(s_id);
        spin_lock(&vha->cmd_list_lock);
        list_for_each_entry(op, &vha->qla_sess_op_cmd_list, cmd_list) {
                uint32_t op_key;
                uint32_t op_lun;

                op_key = sid_to_key(op->atio.u.isp24.fcp_hdr.s_id);
                op_lun = scsilun_to_int(
                        (struct scsi_lun *)&op->atio.u.isp24.fcp_cmnd.lun);
                if (op_key == key && op_lun == lun)
                        op->aborted = true;
        }
        list_for_each_entry(cmd, &vha->qla_cmd_list, cmd_list) {
                uint32_t cmd_key;
                uint32_t cmd_lun;

                cmd_key = sid_to_key(cmd->atio.u.isp24.fcp_hdr.s_id);
                cmd_lun = scsilun_to_int(
                        (struct scsi_lun *)&cmd->atio.u.isp24.fcp_cmnd.lun);
                if (cmd_key == key && cmd_lun == lun)
                        cmd->aborted = 1;
        }
        spin_unlock(&vha->cmd_list_lock);
}

/* ha->hardware_lock supposed to be held on entry */
static int __qlt_24xx_handle_abts(struct scsi_qla_host *vha,
        struct abts_recv_from_24xx *abts, struct qla_tgt_sess *sess)
{
        struct qla_hw_data *ha = vha->hw;
        struct se_session *se_sess = sess->se_sess;
        struct qla_tgt_mgmt_cmd *mcmd;
        struct se_cmd *se_cmd;
        u32 lun = 0;
        int rc;
        bool found_lun = false;

        spin_lock(&se_sess->sess_cmd_lock);
        list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
                struct qla_tgt_cmd *cmd =
                        container_of(se_cmd, struct qla_tgt_cmd, se_cmd);
                if (se_cmd->tag == abts->exchange_addr_to_abort) {
                        lun = cmd->unpacked_lun;
                        found_lun = true;
                        break;
                }
        }
        spin_unlock(&se_sess->sess_cmd_lock);

        /* cmd not in LIO lists, look in qla list */
        if (!found_lun) {
                if (abort_cmd_for_tag(vha, abts->exchange_addr_to_abort)) {
                        /* send TASK_ABORT response immediately */
                        qlt_24xx_send_abts_resp(vha, abts, FCP_TMF_CMPL, false);
                        return 0;
                } else {
                        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf081,
                            "unable to find cmd in driver or LIO for tag 0x%x\n",
                            abts->exchange_addr_to_abort);
                        return -ENOENT;
                }
        }

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf00f,
            "qla_target(%d): task abort (tag=%d)\n",
            vha->vp_idx, abts->exchange_addr_to_abort);

        mcmd = mempool_alloc(qla_tgt_mgmt_cmd_mempool, GFP_ATOMIC);
        if (mcmd == NULL) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf051,
                    "qla_target(%d): %s: Allocation of ABORT cmd failed",
                    vha->vp_idx, __func__);
                return -ENOMEM;
        }
        memset(mcmd, 0, sizeof(*mcmd));

        mcmd->sess = sess;
        memcpy(&mcmd->orig_iocb.abts, abts, sizeof(mcmd->orig_iocb.abts));
        mcmd->reset_count = vha->hw->chip_reset;

        rc = ha->tgt.tgt_ops->handle_tmr(mcmd, lun, TMR_ABORT_TASK,
            abts->exchange_addr_to_abort);
        if (rc != 0) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf052,
                    "qla_target(%d):  tgt_ops->handle_tmr()"
                    " failed: %d", vha->vp_idx, rc);
                mempool_free(mcmd, qla_tgt_mgmt_cmd_mempool);
                return -EFAULT;
        }

        return 0;
}

/*
 * ha->hardware_lock supposed to be held on entry. Might drop it, then reaquire
 */
static void qlt_24xx_handle_abts(struct scsi_qla_host *vha,
        struct abts_recv_from_24xx *abts)
{
        struct qla_hw_data *ha = vha->hw;
        struct qla_tgt_sess *sess;
        uint32_t tag = abts->exchange_addr_to_abort;
        uint8_t s_id[3];
        int rc;
        unsigned long flags;

        if (le32_to_cpu(abts->fcp_hdr_le.parameter) & ABTS_PARAM_ABORT_SEQ) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf053,
                    "qla_target(%d): ABTS: Abort Sequence not "
                    "supported\n", vha->vp_idx);
                qlt_24xx_send_abts_resp(vha, abts, FCP_TMF_REJECTED, false);
                return;
        }

        if (tag == ATIO_EXCHANGE_ADDRESS_UNKNOWN) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf010,
                    "qla_target(%d): ABTS: Unknown Exchange "
                    "Address received\n", vha->vp_idx);
                qlt_24xx_send_abts_resp(vha, abts, FCP_TMF_REJECTED, false);
                return;
        }

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf011,
            "qla_target(%d): task abort (s_id=%x:%x:%x, "
            "tag=%d, param=%x)\n", vha->vp_idx, abts->fcp_hdr_le.s_id[2],
            abts->fcp_hdr_le.s_id[1], abts->fcp_hdr_le.s_id[0], tag,
            le32_to_cpu(abts->fcp_hdr_le.parameter));

        s_id[0] = abts->fcp_hdr_le.s_id[2];
        s_id[1] = abts->fcp_hdr_le.s_id[1];
        s_id[2] = abts->fcp_hdr_le.s_id[0];

        spin_lock_irqsave(&ha->tgt.sess_lock, flags);
        sess = ha->tgt.tgt_ops->find_sess_by_s_id(vha, s_id);
        if (!sess) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf012,
                    "qla_target(%d): task abort for non-existant session\n",
                    vha->vp_idx);
                rc = qlt_sched_sess_work(vha->vha_tgt.qla_tgt,
                    QLA_TGT_SESS_WORK_ABORT, abts, sizeof(*abts));

                spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);

                if (rc != 0) {
                        qlt_24xx_send_abts_resp(vha, abts, FCP_TMF_REJECTED,
                            false);
                }
                return;
        }
        spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);


        if (sess->deleted == QLA_SESS_DELETION_IN_PROGRESS) {
                qlt_24xx_send_abts_resp(vha, abts, FCP_TMF_REJECTED, false);
                return;
        }

        rc = __qlt_24xx_handle_abts(vha, abts, sess);
        if (rc != 0) {
                ql_dbg(ql_dbg_tgt_mgt, vha, 0xf054,
                    "qla_target(%d): __qlt_24xx_handle_abts() failed: %d\n",
                    vha->vp_idx, rc);
                qlt_24xx_send_abts_resp(vha, abts, FCP_TMF_REJECTED, false);
                return;
        }
}

/*
 * ha->hardware_lock supposed to be held on entry. Might drop it, then reaquire
 */
static void qlt_24xx_send_task_mgmt_ctio(struct scsi_qla_host *ha,
        struct qla_tgt_mgmt_cmd *mcmd, uint32_t resp_code)
{
        struct atio_from_isp *atio = &mcmd->orig_iocb.atio;
        struct ctio7_to_24xx *ctio;
        uint16_t temp;

        ql_dbg(ql_dbg_tgt, ha, 0xe008,
            "Sending task mgmt CTIO7 (ha=%p, atio=%p, resp_code=%x\n",
            ha, atio, resp_code);

        /* Send marker if required */
        if (qlt_issue_marker(ha, 1) != QLA_SUCCESS)
                return;

        ctio = (struct ctio7_to_24xx *)qla2x00_alloc_iocbs(ha, NULL);
        if (ctio == NULL) {
                ql_dbg(ql_dbg_tgt, ha, 0xe04c,
                    "qla_target(%d): %s failed: unable to allocate "
                    "request packet\n", ha->vp_idx, __func__);
                return;
        }

        ctio->entry_type = CTIO_TYPE7;
        ctio->entry_count = 1;
        ctio->handle = QLA_TGT_SKIP_HANDLE | CTIO_COMPLETION_HANDLE_MARK;
        ctio->nport_handle = mcmd->sess->loop_id;
        ctio->timeout = cpu_to_le16(QLA_TGT_TIMEOUT);
        ctio->vp_index = ha->vp_idx;
        ctio->initiator_id[0] = atio->u.isp24.fcp_hdr.s_id[2];
        ctio->initiator_id[1] = atio->u.isp24.fcp_hdr.s_id[1];
        ctio->initiator_id[2] = atio->u.isp24.fcp_hdr.s_id[0];
        ctio->exchange_addr = atio->u.isp24.exchange_addr;
        ctio->u.status1.flags = (atio->u.isp24.attr << 9) |
            cpu_to_le16(CTIO7_FLAGS_STATUS_MODE_1 | CTIO7_FLAGS_SEND_STATUS);
        temp = be16_to_cpu(atio->u.isp24.fcp_hdr.ox_id);
        ctio->u.status1.ox_id = cpu_to_le16(temp);
        ctio->u.status1.scsi_status =
            cpu_to_le16(SS_RESPONSE_INFO_LEN_VALID);
        ctio->u.status1.response_len = cpu_to_le16(8);
        ctio->u.status1.sense_data[0] = resp_code;

        /* Memory Barrier */
        wmb();
        qla2x00_start_iocbs(ha, ha->req);
}

void qlt_free_mcmd(struct qla_tgt_mgmt_cmd *mcmd)
{
        mempool_free(mcmd, qla_tgt_mgmt_cmd_mempool);
}
EXPORT_SYMBOL(qlt_free_mcmd);

/* callback from target fabric module code */
void qlt_xmit_tm_rsp(struct qla_tgt_mgmt_cmd *mcmd)
{
        struct scsi_qla_host *vha = mcmd->sess->vha;
        struct qla_hw_data *ha = vha->hw;
        unsigned long flags;

        ql_dbg(ql_dbg_tgt_mgt, vha, 0xf013,
            "TM response mcmd (%p) status %#x state %#x",
            mcmd, mcmd->fc_tm_rsp, mcmd->flags);

        spin_lock_irqsave(&ha->hardware_lock, flags);

        if (!vha->flags.online || mcmd->reset_count != ha->chip_reset) {
                /*
                 * Either the port is not online or this request was from
                 * previous life, just abort the processing.
                 */
                ql_dbg(ql_dbg_async, vha, 0xe100,
                        "RESET-TMR online/active/old-count/new-count = %d/%d/%d/%d.\n",
                        vha->flags.online, qla2x00_reset_active(vha),
                        mcmd->reset_count, ha->chip_reset);
                ha->tgt.tgt_ops->free_mcmd(mcmd);
                spin_unlock_irqrestore(&ha->hardware_lock, flags);
                return;
        }

        if (mcmd->flags == QLA24XX_MGMT_SEND_NACK)
                qlt_send_notify_ack(vha, &mcmd->orig_iocb.imm_ntfy,
                    0, 0, 0, 0, 0, 0);
        else {
                if (mcmd->orig_iocb.atio.u.raw.entry_type == ABTS_RECV_24XX)
                        qlt_24xx_send_abts_resp(vha, &mcmd->orig_iocb.abts,
                            mcmd->fc_tm_rsp, false);
                else
                        qlt_24xx_send_task_mgmt_ctio(vha, mcmd,
                            mcmd->fc_tm_rsp);
        }
        /*
         * Make the callback for ->free_mcmd() to queue_work() and invoke
         * target_put_sess_cmd() to drop cmd_kref to 1.  The final
         * target_put_sess_cmd() call will be made from TFO->check_stop_free()
         * -> tcm_qla2xxx_check_stop_free() to release the TMR associated se_cmd
         * descriptor after TFO->queue_tm_rsp() -> tcm_qla2xxx_queue_tm_rsp() ->
         * qlt_xmit_tm_rsp() returns here..
         */
        ha->tgt.tgt_ops->free_mcmd(mcmd);
        spin_unlock_irqrestore(&ha->hardware_lock, flags);
}
EXPORT_SYMBOL(qlt_xmit_tm_rsp);

/* No locks */
static int qlt_pci_map_calc_cnt(struct qla_tgt_prm *prm)
{
        struct qla_tgt_cmd *cmd = prm->cmd;

        BUG_ON(cmd->sg_cnt == 0);

        prm->sg = (struct scatterlist *)cmd->sg;
        prm->seg_cnt = pci_map_sg(prm->tgt->ha->pdev, cmd->sg,
            cmd->sg_cnt, cmd->dma_data_direction);
        if (unlikely(prm->seg_cnt == 0))
                goto out_err;

        prm->cmd->sg_mapped = 1;

        if (cmd->se_cmd.prot_op == TARGET_PROT_NORMAL) {
                /*
                 * If greater than four sg entries then we need to allocate
                 * the continuation entries
                 */
                if (prm->seg_cnt > prm->tgt->datasegs_per_cmd)
                        prm->req_cnt += DIV_ROUND_UP(prm->seg_cnt -
                        prm->tgt->datasegs_per_cmd,
                        prm->tgt->datasegs_per_cont);
        } else {
                /* DIF */
                if ((cmd->se_cmd.prot_op == TARGET_PROT_DIN_INSERT) ||
                    (cmd->se_cmd.prot_op == TARGET_PROT_DOUT_STRIP)) {
                        prm->seg_cnt = DIV_ROUND_UP(cmd->bufflen, cmd->blk_sz);
                        prm->tot_dsds = prm->seg_cnt;
                } else
                        prm->tot_dsds = prm->seg_cnt;

                if (cmd->prot_sg_cnt) {
                        prm->prot_sg      = cmd->prot_sg;
                        prm->prot_seg_cnt = pci_map_sg(prm->tgt->ha->pdev,
                                cmd->prot_sg, cmd->prot_sg_cnt,
                                cmd->dma_data_direction);
                        if (unlikely(prm->prot_seg_cnt == 0))
                                goto out_err;

                        if ((cmd->se_cmd.prot_op == TARGET_PROT_DIN_INSERT) ||
                            (cmd->se_cmd.prot_op == TARGET_PROT_DOUT_STRIP)) {
                                /* Dif Bundling not support here */
                                prm->prot_seg_cnt = DIV_ROUND_UP(cmd->bufflen,
                                                                cmd->blk_sz);
                                prm->tot_dsds += prm->prot_seg_cnt;
                        } else
                                prm->tot_dsds += prm->prot_seg_cnt;
                }
        }

        return 0;

out_err:
        ql_dbg(ql_dbg_tgt, prm->cmd->vha, 0xe04d,
            "qla_target(%d): PCI mapping failed: sg_cnt=%d",
            0, prm->cmd->sg_cnt);
        return -1;
}

static void qlt_unmap_sg(struct scsi_qla_host *vha, struct qla_tgt_cmd *cmd)
{
        struct qla_hw_data *ha = vha->hw;

        if (!cmd->sg_mapped)
                return;

        pci_unmap_sg(ha->pdev, cmd->sg, cmd->sg_cnt, cmd->dma_data_direction);
        cmd->sg_mapped = 0;

        if (cmd->prot_sg_cnt)
                pci_unmap_sg(ha->pdev, cmd->prot_sg, cmd->prot_sg_cnt,
                        cmd->dma_data_direction);

        if (cmd->ctx_dsd_alloced)
                qla2x00_clean_dsd_pool(ha, NULL, cmd);

        if (cmd->ctx)
                dma_pool_free(ha->dl_dma_pool, cmd->ctx, cmd->ctx->crc_ctx_dma);
}

static int qlt_check_reserve_free_req(struct scsi_qla_host *vha,
        uint32_t req_cnt)
{
        uint32_t cnt, cnt_in;

        if (vha->req->cnt < (req_cnt + 2)) {
                cnt = (uint16_t)RD_REG_DWORD(vha->req->req_q_out);
                cnt_in = (uint16_t)RD_REG_DWORD(vha->req->req_q_in);

                if  (vha->req->ring_index < cnt)
                        vha->req->cnt = cnt - vha->req->ring_index;
                else
                        vha->req->cnt = vha->req->length -
                            (vha->req->ring_index - cnt);

                if (unlikely(vha->req->cnt < (req_cnt + 2))) {
                        ql_dbg(ql_dbg_io, vha, 0x305a,
                            "qla_target(%d): There is no room in the request ring: vha->req->ring_index=%d, vha->req->cnt=%d, req_cnt=%d Req-out=%d Req-in=%d Req-Length=%d\n",
                            vha->vp_idx, vha->req->ring_index,
                            vha->req->cnt, req_cnt, cnt, cnt_in,
                            vha->req->length);
                        return -EAGAIN;
                }
        }

        vha->req->cnt -= req_cnt;

        return 0;
}

/*
 * ha->hardware_lock supposed to be held on entry. Might drop it, then reaquire
 */
static inline void *qlt_get_req_pkt(struct scsi_qla_host *vha)
{
        /* Adjust ring index. */
        vha->req->ring_index++;
        if (vha->req->ring_index == vha->req->length) {
                vha->req->ring_index = 0;
                vha->req->ring_ptr = vha->req->ring;
        } else {
                vha->req->ring_ptr++;
        }
        return (cont_entry_t *)vha->req->ring_ptr;
}

/* ha->hardware_lock supposed to be held on entry */
static inline uint32_t qlt_make_handle(struct scsi_qla_host *vha)
{
        struct qla_hw_data *ha = vha->hw;
        uint32_t h;

        h = ha->tgt.current_handle;
        /* always increment cmd handle */
        do {
                ++h;
                if (h > DEFAULT_OUTSTANDING_COMMANDS)
                        h = 1; /* 0 is QLA_TGT_NULL_HANDLE */
                if (h == ha->tgt.current_handle) {
                        ql_dbg(ql_dbg_io, vha, 0x305b,
                            "qla_target(%d): Ran out of "
                            "empty cmd slots in ha %p\n", vha->vp_idx, ha);
                        h = QLA_TGT_NULL_HANDLE;
                        break;
                }
        } while ((h == QLA_TGT_NULL_HANDLE) ||
            (h == QLA_TGT_SKIP_HANDLE) ||
            (ha->tgt.cmds[h-1] != NULL));

        if (h != QLA_TGT_NULL_HANDLE)
                ha->tgt.current_handle = h;

        return h;
}

/* ha->hardware_lock supposed to be held on entry */
static int qlt_24xx_build_ctio_pkt(struct qla_tgt_prm *prm,
        struct scsi_qla_host *vha)
{
        uint32_t h;
        struct ctio7_to_24xx *pkt;
        struct qla_hw_data *ha = vha->hw;
        struct atio_from_isp *atio = &prm->cmd->atio;
        uint16_t temp;

        pkt = (struct ctio7_to_24xx *)vha->req->ring_ptr;
        prm->pkt = pkt;
        memset(pkt, 0, sizeof(*pkt));

        pkt->entry_type = CTIO_TYPE7;
        pkt->entry_count = (uint8_t)prm->req_cnt;
        pkt->vp_index = vha->vp_idx;

        h = qlt_make_handle(vha);
        if (unlikely(h == QLA_TGT_NULL_HANDLE)) {
                /*
                 * CTIO type 7 from the firmware doesn't provide a way to
                 * know the initiator's LOOP ID, hence we can't find
                 * the session and, so, the command.
                 */
                return -EAGAIN;
        } else
                ha->tgt.cmds[h-1] = prm->cmd;

        pkt->handle = h | CTIO_COMPLETION_HANDLE_MARK;
        pkt->nport_handle = prm->cmd->loop_id;
        pkt->timeout = cpu_to_le16(QLA_TGT_TIMEOUT);
        pkt->initiator_id[0] = atio->u.isp24.fcp_hdr.s_id[2];
        pkt->initiator_id[1] = atio->u.isp24.fcp_hdr.s_id[1];
        pkt->initiator_id[2] = atio->u.isp24.fcp_hdr.s_id[0];
        pkt->exchange_addr = atio->u.isp24.exchange_addr;
        pkt->u.status0.flags |= (atio->u.isp24.attr << 9);
        temp = be16_to_cpu(atio->u.isp24.fcp_hdr.ox_id);
        pkt->u.status0.ox_id = cpu_to_le16(temp);
        pkt->u.status0.relative_offset = cpu_to_le32(prm->cmd->offset);

        return 0;
}

/*
 * ha->hardware_lock supposed to be held on entry. We have already made sure
 * that there is sufficient amount of request entries to not drop it.
 */
static void qlt_load_cont_data_segments(struct qla_tgt_prm *prm,
        struct scsi_qla_host *vha)
{
        int cnt;
        uint32_t *dword_ptr;
        int enable_64bit_addressing = prm->tgt->tgt_enable_64bit_addr;

        /* Build continuation packets */

        while (prm->seg_cnt > 0) {
                cont_a64_entry_t *cont_pkt64 =
                        (cont_a64_entry_t *)qlt_get_req_pkt(vha);

                /*
                 * Make sure that from cont_pkt64 none of
                 * 64-bit specific fields used for 32-bit
                 * addressing. Cast to (cont_entry_t *) for
                 * that.
                 */

                memset(cont_pkt64, 0, sizeof(*cont_pkt64));

                cont_pkt64->entry_count = 1;
                cont_pkt64->sys_define = 0;

                if (enable_64bit_addressing) {
                        cont_pkt64->entry_type = CONTINUE_A64_TYPE;
                        dword_ptr =
                            (uint32_t *)&cont_pkt64->dseg_0_address;
                } else {
                        cont_pkt64->entry_type = CONTINUE_TYPE;
                        dword_ptr =
                            (uint32_t *)&((cont_entry_t *)
                                cont_pkt64)->dseg_0_address;
                }

                /* Load continuation entry data segments */
                for (cnt = 0;
                    cnt < prm->tgt->datasegs_per_cont && prm->seg_cnt;
                    cnt++, prm->seg_cnt--) {
                        *dword_ptr++ =
                            cpu_to_le32(pci_dma_lo32
                                (sg_dma_address(prm->sg)));
                        if (enable_64bit_addressing) {
                                *dword_ptr++ =
                                    cpu_to_le32(pci_dma_hi32
                                        (sg_dma_address
                                        (prm->sg)));
                        }
                        *dword_ptr++ = cpu_to_le32(sg_dma_len(prm->sg));

                        prm->sg = sg_next(prm->sg);
                }
        }
}

/*
 * ha->hardware_lock supposed to be held on entry. We have already made sure
 * that there is sufficient amount of request entries to not drop it.
 */
static void qlt_load_data_segments(struct qla_tgt_prm *prm,
        struct scsi_qla_host *vha)
{
        int cnt;
        uint32_t *dword_ptr;
        int enable_64bit_addressing = prm->tgt->tgt_enable_64bit_addr;
        struct ctio7_to_24xx *pkt24 = (struct ctio7_to_24xx *)prm->pkt;

        pkt24->u.status0.transfer_length = cpu_to_le32(prm->cmd->bufflen);

        /* Setup packet address segment pointer */
        dword_ptr = pkt24->u.status0.dseg_0_address;

        /* Set total data segment count */
        if (prm->seg_cnt)
                pkt24->dseg_count = cpu_to_le16(prm->seg_cnt);

        if (prm->seg_cnt == 0) {
                /* No data transfer */
                *dword_ptr++ = 0;
                *dword_ptr = 0;
                return;
        }

        /* If scatter gather */

        /* Load command entry data segments */
        for (cnt = 0;
            (cnt < prm->tgt->datasegs_per_cmd) && prm->seg_cnt;
            cnt++, prm->seg_cnt--) {
                *dword_ptr++ =
                    cpu_to_le32(pci_dma_lo32(sg_dma_address(prm->sg)));
                if (enable_64bit_addressing) {
                        *dword_ptr++ =
                            cpu_to_le32(pci_dma_hi32(
                                sg_dma_address(prm->sg)));
                }
                *dword_ptr++ = cpu_to_le32(sg_dma_len(prm->sg));

                prm->sg = sg_next(prm->sg);
        }

        qlt_load_cont_data_segments(prm, vha);
}

static inline int qlt_has_data(struct qla_tgt_cmd *cmd)
{
        return cmd->bufflen > 0;
}

/*
 * Called without ha->hardware_lock held
 */
static int qlt_pre_xmit_response(struct qla_tgt_cmd *cmd,
        struct qla_tgt_prm *prm, int xmit_type, uint8_t scsi_status,
        uint32_t *full_req_cnt)
{
        struct qla_tgt *tgt = cmd->tgt;
        struct scsi_qla_host *vha = tgt->vha;
        struct qla_hw_data *ha = vha->hw;
        struct se_cmd *se_cmd = &cmd->se_cmd;

        prm->cmd = cmd;
        prm->tgt = tgt;
        prm->rq_result = scsi_status;
        prm->sense_buffer = &cmd->sense_buffer[0];
        prm->sense_buffer_len = TRANSPORT_SENSE_BUFFER;
        prm->sg = NULL;
        prm->seg_cnt = -1;
        prm->req_cnt = 1;
        prm->add_status_pkt = 0;

        /* Send marker if required */
        if (qlt_issue_marker(vha, 0) != QLA_SUCCESS)
                return -EFAULT;

        if ((xmit_type & QLA_TGT_XMIT_DATA) && qlt_has_data(cmd)) {
                if  (qlt_pci_map_calc_cnt(prm) != 0)
                        return -EAGAIN;
        }

        *full_req_cnt = prm->req_cnt;

        if (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
                prm->residual = se_cmd->residual_count;
                ql_dbg(ql_dbg_io + ql_dbg_verbose, vha, 0x305c,
                    "Residual underflow: %d (tag %lld, op %x, bufflen %d, rq_result %x)\n",
                       prm->residual, se_cmd->tag,
                       se_cmd->t_task_cdb ? se_cmd->t_task_cdb[0] : 0,
                       cmd->bufflen, prm->rq_result);
                prm->rq_result |= SS_RESIDUAL_UNDER;
        } else if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
                prm->residual = se_cmd->residual_count;
                ql_dbg(ql_dbg_io, vha, 0x305d,
                    "Residual overflow: %d (tag %lld, op %x, bufflen %d, rq_result %x)\n",
                       prm->residual, se_cmd->tag, se_cmd->t_task_cdb ?
                       se_cmd->t_task_cdb[0] : 0, cmd->bufflen, prm->rq_result);
                prm->rq_result |= SS_RESIDUAL_OVER;
        }

        if (xmit_type & QLA_TGT_XMIT_STATUS) {
                /*
                 * If QLA_TGT_XMIT_DATA is not set, add_status_pkt will be
                 * ignored in *xmit_response() below
                 */
                if (qlt_has_data(cmd)) {
                        if (QLA_TGT_SENSE_VALID(prm->sense_buffer) ||
                            (IS_FWI2_CAPABLE(ha) &&
                            (prm->rq_result != 0))) {
                                prm->add_status_pkt = 1;
                                (*full_req_cnt)++;
                        }
                }
        }

        return 0;
}

static inline int qlt_need_explicit_conf(struct qla_hw_data *ha,
        struct qla_tgt_cmd *cmd, int sending_sense)
{
        if (ha->tgt.enable_class_2)
                return 0;

        if (sending_sense)
                return cmd->conf_compl_supported;
        else
                return ha->tgt.enable_explicit_conf &&
                    cmd->conf_compl_supported;
}

#ifdef CONFIG_QLA_TGT_DEBUG_SRR
/*
 *  Original taken from the XFS code
 */
static unsigned long qlt_srr_random(void)
{
        static int Inited;
        static unsigned long RandomValue;
        static DEFINE_SPINLOCK(lock);
        /* cycles pseudo-randomly through all values between 1 and 2^31 - 2 */
        register long rv;
        register long lo;
        register long hi;
        unsigned long flags;

        spin_lock_irqsave(&lock, flags);
        if (!Inited) {
                RandomValue = jiffies;
                Inited = 1;
        }
        rv = RandomValue;
        hi = rv / 127773;
        lo = rv % 127773;
        rv = 16807 * lo - 2836 * hi;
        if (rv <= 0)
                rv += 2147483647;
        RandomValue = rv;
        spin_unlock_irqrestore(&lock, flags);
        return rv;
}

static void qlt_check_srr_debug(struct qla_tgt_cmd *cmd, int *xmit_type)
{
#if 0 /* This is not a real status packets lost, so it won't lead to SRR */
        if ((*xmit_type & QLA_TGT_XMIT_STATUS) && (qlt_srr_random() % 200)
            == 50) {
                *xmit_type &= ~QLA_TGT_XMIT_STATUS;
                ql_dbg(ql_dbg_tgt_mgt, cmd->vha, 0xf015,
                    "Dropping cmd %p (tag %d) status", cmd, se_cmd->tag);
        }
#endif
        /*
         * It's currently not possible to simulate SRRs for FCP_WRITE without
         * a physical link layer failure, so don't even try here..
         */
        if (cmd->dma_data_direction != DMA_FROM_DEVICE)
                return;

        if (qlt_has_data(cmd) && (cmd->sg_cnt > 1) &&
            ((qlt_srr_random() % 100) == 20)) {
                int i, leave = 0;
                unsigned int tot_len = 0;

                while (leave == 0)
                        leave = qlt_srr_random() % cmd->sg_cnt;

                for (i = 0; i < leave; i++)
                        tot_len += cmd->sg[i].length;

                ql_dbg(ql_dbg_tgt_mgt, cmd->vha, 0xf016,
                    "Cutting cmd %p (tag %d) buffer"
                    " tail to len %d, sg_cnt %d (cmd->bufflen %d,"
                    " cmd->sg_cnt %d)", cmd, se_cmd->tag, tot_len, leave,
                    cmd->bufflen, cmd->sg_cnt);

                cmd->bufflen = tot_len;
                cmd->sg_cnt = leave;
        }

        if (qlt_has_data(cmd) && ((qlt_srr_random() % 100) == 70)) {
                unsigned int offset = qlt_srr_random() % cmd->bufflen;

                ql_dbg(ql_dbg_tgt_mgt, cmd->vha, 0xf017,
                    "Cutting cmd %p (tag %d) buffer head "
                    "to offset %d (cmd->bufflen %d)", cmd, se_cmd->tag, offset,
                    cmd->bufflen);
                if (offset == 0)
                        *xmit_type &= ~QLA_TGT_XMIT_DATA;
                else if (qlt_set_data_offset(cmd, offset)) {
                        ql_dbg(ql_dbg_tgt_mgt, cmd->vha, 0xf018,
                            "qlt_set_data_offset() failed (tag %d)", se_cmd->tag);
                }
        }
}
#else
static inline void qlt_check_srr_debug(struct qla_tgt_cmd *cmd, int *xmit_type)
{}
#endif

static void qlt_24xx_init_ctio_to_isp(struct ctio7_to_24xx *ctio,
        struct qla_tgt_prm *prm)
{
        prm->sense_buffer_len = min_t(uint32_t, prm->sense_buffer_len,
            (uint32_t)sizeof(ctio->u.status1.sense_data));
        ctio->u.status0.flags |= cpu_to_le16(CTIO7_FLAGS_SEND_STATUS);
        if (qlt_need_explicit_conf(prm->tgt->ha, prm->cmd, 0)) {
                ctio->u.status0.flags |= cpu_to_le16(
                    CTIO7_FLAGS_EXPLICIT_CONFORM |
                    CTIO7_FLAGS_CONFORM_REQ);
        }
        ctio->u.status0.residual = cpu_to_le32(prm->residual);
        ctio->u.status0.scsi_status = cpu_to_le16(prm->rq_result);
        if (QLA_TGT_SENSE_VALID(prm->sense_buffer)) {
                int i;

                if (qlt_need_explicit_conf(prm->tgt->ha, prm->cmd, 1)) {
                        if (prm->cmd->se_cmd.scsi_status != 0) {
                                ql_dbg(ql_dbg_tgt, prm->cmd->vha, 0xe017,
                                    "Skipping EXPLICIT_CONFORM and "
                                    "CTIO7_FLAGS_CONFORM_REQ for FCP READ w/ "
                                    "non GOOD status\n");
                                goto skip_explict_conf;
                        }
                        ctio->u.status1.flags |= cpu_to_le16(
                            CTIO7_FLAGS_EXPLICIT_CONFORM |
                            CTIO7_FLAGS_CONFORM_REQ);
                }
skip_explict_conf:
                ctio->u.status1.flags &=
                    ~cpu_to_le16(CTIO7_FLAGS_STATUS_MODE_0);
                ctio->u.status1.flags |=
                    cpu_to_le16(CTIO7_FLAGS_STATUS_MODE_1);
                ctio->u.status1.scsi_status |=
                    cpu_to_le16(SS_SENSE_LEN_VALID);
                ctio->u.status1.sense_length =
                    cpu_to_le16(prm->sense_buffer_len);
                for (i = 0; i < prm->sense_buffer_len/4; i++)
                        ((uint32_t *)ctio->u.status1.sense_data)[i] =
                                cpu_to_be32(((uint32_t *)prm->sense_buffer)[i]);
#if 0
                if (unlikely((prm->sense_buffer_len % 4) != 0)) {
                        static int q;
                        if (q < 10) {
                                ql_dbg(ql_dbg_tgt, vha, 0xe04f,
                                    "qla_target(%d): %d bytes of sense "
                                    "lost", prm->tgt->ha->vp_idx,
                                    prm->sense_buffer_len % 4);
                                q++;
                        }
                }
#endif
        } else {
                ctio->u.status1.flags &=
                    ~cpu_to_le16(CTIO7_FLAGS_STATUS_MODE_0);
                ctio->u.status1.flags |=
                    cpu_to_le16(CTIO7_FLAGS_STATUS_MODE_1);
                ctio->u.status1.sense_length = 0;
                memset(ctio->u.status1.sense_data, 0,
                    sizeof(ctio->u.status1.sense_data));
        }

        /* Sense with len > 24, is it possible ??? */
}



/* diff  */
static inline int
qlt_hba_err_chk_enabled(struct se_cmd *se_cmd)
{
        /*
         * Uncomment when corresponding SCSI changes are done.
         *
         if (!sp->cmd->prot_chk)
         return 0;
         *
         */
        switch (se_cmd->prot_op) {
        case TARGET_PROT_DOUT_INSERT:
        case TARGET_PROT_DIN_STRIP:
                if (ql2xenablehba_err_chk >= 1)
                        return 1;
                break;
        case TARGET_PROT_DOUT_PASS:
        case TARGET_PROT_DIN_PASS:
                if (ql2xenablehba_err_chk >= 2)
                        return 1;
                break;
        case TARGET_PROT_DIN_INSERT:
        case TARGET_PROT_DOUT_STRIP:
                return 1;
        default:
                break;
        }
        return 0;
}

/*
 * qla24xx_set_t10dif_tags_from_cmd - Extract Ref and App tags from SCSI command
 *
 */
static inline void
qlt_set_t10dif_tags(struct se_cmd *se_cmd, struct crc_context *ctx)
{
        uint32_t lba = 0xffffffff & se_cmd->t_task_lba;

        /* wait til Mode Sense/Select cmd, modepage Ah, subpage 2
         * have been immplemented by TCM, before AppTag is avail.
         * Look for modesense_handlers[]
         */
        ctx->app_tag = 0;
        ctx->app_tag_mask[0] = 0x0;
        ctx->app_tag_mask[1] = 0x0;

        switch (se_cmd->prot_type) {
        case TARGET_DIF_TYPE0_PROT:
                /*
                 * No check for ql2xenablehba_err_chk, as it would be an
                 * I/O error if hba tag generation is not done.
                 */
                ctx->ref_tag = cpu_to_le32(lba);

                if (!qlt_hba_err_chk_enabled(se_cmd))
                        break;

                /* enable ALL bytes of the ref tag */
                ctx->ref_tag_mask[0] = 0xff;
                ctx->ref_tag_mask[1] = 0xff;
                ctx->ref_tag_mask[2] = 0xff;
                ctx->ref_tag_mask[3] = 0xff;
                break;
        /*
         * For TYpe 1 protection: 16 bit GUARD tag, 32 bit REF tag, and
         * 16 bit app tag.
         */
        case TARGET_DIF_TYPE1_PROT:
                ctx->ref_tag = cpu_to_le32(lba);

                if (!qlt_hba_err_chk_enabled(se_cmd))
                        break;

                /* enable ALL bytes of the ref tag */
                ctx->ref_tag_mask[0] = 0xff;
                ctx->ref_tag_mask[1] = 0xff;
                ctx->ref_tag_mask[2] = 0xff;
                ctx->ref_tag_mask[3] = 0xff;
                break;
        /*
         * For TYPE 2 protection: 16 bit GUARD + 32 bit REF tag has to
         * match LBA in CDB + N
         */
        case TARGET_DIF_TYPE2_PROT:
                ctx->ref_tag = cpu_to_le32(lba);

                if (!qlt_hba_err_chk_enabled(se_cmd))
                        break;

                /* enable ALL bytes of the ref tag */
                ctx->ref_tag_mask[0] = 0xff;
                ctx->ref_tag_mask[1] = 0xff;
                ctx->ref_tag_mask[2] = 0xff;
                ctx->ref_tag_mask[3] = 0xff;
                break;

        /* For Type 3 protection: 16 bit GUARD only */
        case TARGET_DIF_TYPE3_PROT:
                ctx->ref_tag_mask[0] = ctx->ref_tag_mask[1] =
                        ctx->ref_tag_mask[2] = ctx->ref_tag_mask[3] = 0x00;
                break;
        }
}


static inline int
qlt_build_ctio_crc2_pkt(struct qla_tgt_prm *prm, scsi_qla_host_t *vha)
{
        uint32_t                *cur_dsd;
        uint32_t                transfer_length = 0;
        uint32_t                data_bytes;
        uint32_t                dif_bytes;
        uint8_t                 bundling = 1;
        uint8_t                 *clr_ptr;
        struct crc_context      *crc_ctx_pkt = NULL;
        struct qla_hw_data      *ha;
        struct ctio_crc2_to_fw  *pkt;
        dma_addr_t              crc_ctx_dma;
        uint16_t                fw_prot_opts = 0;
        struct qla_tgt_cmd      *cmd = prm->cmd;
        struct se_cmd           *se_cmd = &cmd->se_cmd;
        uint32_t h;
        struct atio_from_isp *atio = &prm->cmd->atio;
        uint16_t t16;

        ha = vha->hw;

        pkt = (struct ctio_crc2_to_fw *)vha->req->ring_ptr;
        prm->pkt = pkt;
        memset(pkt, 0, sizeof(*pkt));

        ql_dbg(ql_dbg_tgt, vha, 0xe071,
                "qla_target(%d):%s: se_cmd[%p] CRC2 prot_op[0x%x] cmd prot sg:cnt[%p:%x] lba[%llu]\n",
                vha->vp_idx, __func__, se_cmd, se_cmd->prot_op,
                prm->prot_sg, prm->prot_seg_cnt, se_cmd->t_task_lba);

        if ((se_cmd->prot_op == TARGET_PROT_DIN_INSERT) ||
            (se_cmd->prot_op == TARGET_PROT_DOUT_STRIP))
                bundling = 0;

        /* Compute dif len and adjust data len to incude protection */
        data_bytes = cmd->bufflen;
        dif_bytes  = (data_bytes / cmd->blk_sz) * 8;

        switch (se_cmd->prot_op) {
        case TARGET_PROT_DIN_INSERT:
        case TARGET_PROT_DOUT_STRIP:
                transfer_length = data_bytes;
                data_bytes += dif_bytes;
                break;

        case TARGET_PROT_DIN_STRIP:
        case TARGET_PROT_DOUT_INSERT:
        case TARGET_PROT_DIN_PASS:
        case TARGET_PROT_DOUT_PASS:
                transfer_length = data_bytes + dif_bytes;
                break;

        default:
                BUG();
                break;
        }

        if (!qlt_hba_err_chk_enabled(se_cmd))
                fw_prot_opts |= 0x10; /* Disable Guard tag checking */
        /* HBA error checking enabled */
        else if (IS_PI_UNINIT_CAPABLE(ha)) {
                if ((se_cmd->prot_type == TARGET_DIF_TYPE1_PROT) ||
                    (se_cmd->prot_type == TARGET_DIF_TYPE2_PROT))
                        fw_prot_opts |= PO_DIS_VALD_APP_ESC;
                else if (se_cmd->prot_type == TARGET_DIF_TYPE3_PROT)
                        fw_prot_opts |= PO_DIS_VALD_APP_REF_ESC;
        }

        switch (se_cmd->prot_op) {
        case TARGET_PROT_DIN_INSERT:
        case TARGET_PROT_DOUT_INSERT:
                fw_prot_opts |= PO_MODE_DIF_INSERT;
                break;
        case TARGET_PROT_DIN_STRIP:
        case TARGET_PROT_DOUT_STRIP:
                fw_prot_opts |= PO_MODE_DIF_REMOVE;
                break;
        case TARGET_PROT_DIN_PASS:
        case TARGET_PROT_DOUT_PASS:
                fw_prot_opts |= PO_MODE_DIF_PASS;
                /* FUTURE: does tcm require T10CRC<->IPCKSUM conversion? */
                break;
        default:/* Normal Request */
                fw_prot_opts |= PO_MODE_DIF_PASS;
                break;
        }


        /* ---- PKT ---- */
        /* Update entry type to indicate Command Type CRC_2 IOCB */
        pkt->entry_type  = CTIO_CRC2;
        pkt->entry_count = 1;
        pkt->vp_index = vha->vp_idx;

        h = qlt_make_handle(vha);
        if (unlikely(h == QLA_TGT_NULL_HANDLE)) {
                /*
                 * CTIO type 7 from the firmware doesn't provide a way to
                 * know the initiator's LOOP ID, hence we can't find
                 * the session and, so, the command.
                 */
                return -EAGAIN;
        } else
                ha->tgt.cmds[h-1] = prm->cmd;


        pkt->handle  = h | CTIO_COMPLETION_HANDLE_MARK;
        pkt->nport_handle = prm->cmd->loop_id;
        pkt->timeout = cpu_to_le16(QLA_TGT_TIMEOUT);
        pkt->initiator_id[0] = atio->u.isp24.fcp_hdr.s_id[2];
        pkt->initiator_id[1] = atio->u.isp24.fcp_hdr.s_id[1];
        pkt->initiator_id[2] = atio->u.isp24.fcp_hdr.s_id[0];
        pkt->exchange_addr   = atio->u.isp24.exchange_addr;

        /* silence compile warning */
        t16 = be16_to_cpu(atio->u.isp24.fcp_hdr.ox_id);
        pkt->ox_id  = cpu_to_le16(t16);

        t16 = (atio->u.isp24.attr << 9);
        pkt->flags |= cpu_to_le16(t16);
        pkt->relative_offset = cpu_to_le32(prm->cmd->offset);

        /* Set transfer direction */
        if (cmd->dma_data_direction == DMA_TO_DEVICE)
                pkt->flags = cpu_to_le16(CTIO7_FLAGS_DATA_IN);
        else if (cmd->dma_data_direction == DMA_FROM_DEVICE)
                pkt->flags = cpu_to_le16(CTIO7_FLAGS_DATA_OUT);


        pkt->dseg_count = prm->tot_dsds;
        /* Fibre channel byte count */
        pkt->transfer_length = cpu_to_le32(transfer_length);


        /* ----- CRC context -------- */

        /* Allocate CRC context from global pool */
        crc_ctx_pkt = cmd->ctx =
            dma_pool_alloc(ha->dl_dma_pool, GFP_ATOMIC, &crc_ctx_dma);

        if (!crc_ctx_pkt)
                goto crc_queuing_error;

        /* Zero out CTX area. */
        clr_ptr = (uint8_t *)crc_ctx_pkt;
        memset(clr_ptr, 0, sizeof(*crc_ctx_pkt));

        crc_ctx_pkt->crc_ctx_dma = crc_ctx_dma;
        INIT_LIST_HEAD(&crc_ctx_pkt->dsd_list);

        /* Set handle */
        crc_ctx_pkt->handle = pkt->handle;

        qlt_set_t10dif_tags(se_cmd, crc_ctx_pkt);

        pkt->crc_context_address[0] = cpu_to_le32(LSD(crc_ctx_dma));
        pkt->crc_context_address[1] = cpu_to_le32(MSD(crc_ctx_dma));
        pkt->crc_context_len = CRC_CONTEXT_LEN_FW;


        if (!bundling) {
                cur_dsd = (uint32_t *) &crc_ctx_pkt->u.nobundling.data_address;
        } else {
                /*
                 * Configure Bundling if we need to fetch interlaving
                 * protection PCI accesses
                 */
                fw_prot_opts |= PO_ENABLE_DIF_BUNDLING;
                crc_ctx_pkt->u.bundling.dif_byte_count = cpu_to_le32(dif_bytes);
                crc_ctx_pkt->u.bundling.dseg_count =
                        cpu_to_le16(prm->tot_dsds - prm->prot_seg_cnt);
                cur_dsd = (uint32_t *) &crc_ctx_pkt->u.bundling.data_address;
        }

        /* Finish the common fields of CRC pkt */
        crc_ctx_pkt->blk_size   = cpu_to_le16(cmd->blk_sz);
        crc_ctx_pkt->prot_opts  = cpu_to_le16(fw_prot_opts);
        crc_ctx_pkt->byte_count = cpu_to_le32(data_bytes);
        crc_ctx_pkt->guard_seed = cpu_to_le16(0);


        /* Walks data segments */
        pkt->flags |= cpu_to_le16(CTIO7_FLAGS_DSD_PTR);

        if (!bundling && prm->prot_seg_cnt) {
                if (qla24xx_walk_and_build_sglist_no_difb(ha, NULL, cur_dsd,
                        prm->tot_dsds, cmd))
                        goto crc_queuing_error;
        } else if (qla24xx_walk_and_build_sglist(ha, NULL, cur_dsd,
                (prm->tot_dsds - prm->prot_seg_cnt), cmd))
                goto crc_queuing_error;

        if (bundling && prm->prot_seg_cnt) {
                /* Walks dif segments */
                pkt->add_flags |= CTIO_CRC2_AF_DIF_DSD_ENA;

                cur_dsd = (uint32_t *) &crc_ctx_pkt->u.bundling.dif_address;
                if (qla24xx_walk_and_build_prot_sglist(ha, NULL, cur_dsd,
                        prm->prot_seg_cnt, cmd))
                        goto crc_queuing_error;
        }
        return QLA_SUCCESS;

crc_queuing_error:
        /* Cleanup will be performed by the caller */

        return QLA_FUNCTION_FAILED;
}


/*
 * Callback to setup response of xmit_type of QLA_TGT_XMIT_DATA and *
 * QLA_TGT_XMIT_STATUS for >= 24xx silicon
 */
int qlt_xmit_response(struct qla_tgt_cmd *cmd, int xmit_type,
        uint8_t scsi_status)
{
        struct scsi_qla_host *vha = cmd->vha;
        struct qla_hw_data *ha = vha->hw;
        struct ctio7_to_24xx *pkt;
        struct qla_tgt_prm prm;
        uint32_t full_req_cnt = 0;
        unsigned long flags = 0;
        int res;

        spin_lock_irqsave(&ha->hardware_lock, flags);
        if (cmd->sess && cmd->sess->deleted == QLA_SESS_DELETION_IN_PROGRESS) {
                cmd->state = QLA_TGT_STATE_PROCESSED;
                if (cmd->sess->logout_completed)
                        /* no need to terminate. FW already freed exchange. */
                        qlt_abort_cmd_on_host_reset(cmd->vha, cmd);
                else
                        qlt_send_term_exchange(vha, cmd, &cmd->atio, 1, 0);
                spin_unlock_irqrestore(&ha->hardware_lock, flags);
                return 0;
        }
        spin_unlock_irqrestore(&ha->hardware_lock, flags);

        memset(&prm, 0, sizeof(prm));
        qlt_check_srr_debug(cmd, &xmit_type);

        ql_dbg(ql_dbg_tgt, cmd->vha, 0xe018,
            "is_send_status=%d, cmd->bufflen=%d, cmd->sg_cnt=%d, cmd->dma_data_direction=%d se_cmd[%p]\n",
            (xmit_type & QLA_TGT_XMIT_STATUS) ?
            1 : 0, cmd->bufflen, cmd->sg_cnt, cmd->dma_data_direction,
            &cmd->se_cmd);

        res = qlt_pre_xmit_response(cmd, &prm, xmit_type, scsi_status,
            &full_req_cnt);
        if (unlikely(res != 0)) {
                return res;
        }

        spin_lock_irqsave(&ha->hardware_lock, flags);

        if (xmit_type == QLA_TGT_XMIT_STATUS)
                vha->tgt_counters.core_qla_snd_status++;
        else
                vha->tgt_counters.core_qla_que_buf++;

        if (!vha->flags.online || cmd->reset_count != ha->chip_reset) {
                /*
                 * Either the port is not online or this request was from
                 * previous life, just abort the processing.
                 */
                cmd->state = QLA_TGT_STATE_PROCESSED;
                qlt_abort_cmd_on_host_reset(cmd->vha, cmd);
                ql_dbg(ql_dbg_async, vha, 0xe101,
                        "RESET-RSP online/active/old-count/new-count = %d/%d/%d/%d.\n",
                        vha->flags.online, qla2x00_reset_active(vha),
                        cmd->reset_count, ha->chip_reset);
                spin_unlock_irqrestore(&ha->hardware_lock, flags);
                return 0;
        }

        /* Does F/W have an IOCBs for this request */
        res = qlt_check_reserve_free_req(vha, full_req_cnt);
        if (unlikely(res))
                goto out_unmap_unlock;

        if (cmd->se_cmd.prot_op && (xmit_type & QLA_TGT_XMIT_DATA))
                res = qlt_build_ctio_crc2_pkt(&prm, vha);
        else
                res = qlt_24xx_build_ctio_pkt(&prm, vha);
        if (unlikely(res != 0)) {
                vha->req->cnt += full_req_cnt;
                goto out_unmap_unlock;
        }

        pkt = (struct ctio7_to_24xx *)prm.pkt;

        if (qlt_has_data(cmd) && (xmit_type & QLA_TGT_XMIT_DATA)) {
                pkt->u.status0.flags |=
                    cpu_to_le16(CTIO7_FLAGS_DATA_IN |
                        CTIO7_FLAGS_STATUS_MODE_0);

                if (cmd->se_cmd.prot_op == TARGET_PROT_NORMAL)
                        qlt_load_data_segments(&prm, vha);

                if (prm.add_status_pkt == 0) {
                        if (xmit_type & QLA_TGT_XMIT_STATUS) {
                                pkt->u.status0.scsi_status =
                                    cpu_to_le16(prm.rq_result);
                                pkt->u.status0.residual =
                                    cpu_to_le32(prm.residual);
                                pkt->u.status0.flags |= cpu_to_le16(
                                    CTIO7_FLAGS_SEND_STATUS);
                                if (qlt_need_explicit_conf(ha, cmd, 0)) {
                                        pkt->u.status0.flags |=
                                            cpu_to_le16(
                                                CTIO7_FLAGS_EXPLICIT_CONFORM |
                                                CTIO7_FLAGS_CONFORM_REQ);
                                }
                        }

                } else {
                        /*
                         * We have already made sure that there is sufficient
                         * amount of request entries to not drop HW lock in
                         * req_pkt().
                         */
                        struct ctio7_to_24xx *ctio =
                                (struct ctio7_to_24xx *)qlt_get_req_pkt(vha);

                        ql_dbg(ql_dbg_io, vha, 0x305e,
                            "Building additional status packet 0x%p.\n",
                            ctio);

                        /*
                         * T10Dif: ctio_crc2_to_fw overlay ontop of
                         * ctio7_to_24xx
                         */
                        memcpy(ctio, pkt, sizeof(*ctio));
                        /* reset back to CTIO7 */
                        ctio->entry_count = 1;
                        ctio->entry_type = CTIO_TYPE7;
                        ctio->dseg_count = 0;
                        ctio->u.status1.flags &= ~cpu_to_le16(
                            CTIO7_FLAGS_DATA_IN);

                        /* Real finish is ctio_m1's finish */
                        pkt->handle |= CTIO_INTERMEDIATE_HANDLE_MARK;
                        pkt->u.status0.flags |= cpu_to_le16(
                            CTIO7_FLAGS_DONT_RET_CTIO);

                        /* qlt_24xx_init_ctio_to_isp will correct
                         * all neccessary fields that's part of CTIO7.
                         * There should be no residual of CTIO-CRC2 data.
                         */
                        qlt_24xx_init_ctio_to_isp((struct ctio7_to_24xx *)ctio,
                            &prm);
                        pr_debug("Status CTIO7: %p\n", ctio);
                }
        } else
                qlt_24xx_init_ctio_to_isp(pkt, &prm);


        cmd->state = QLA_TGT_STATE_PROCESSED; /* Mid-level is done processing */
        cmd->cmd_sent_to_fw = 1;

        /* Memory Barrier */
        wmb();
        qla2x00_start_iocbs(vha, vha->req);
        spin_unlock_irqrestore(&ha->hardware_lock, flags);

        return 0;

out_unmap_unlock:
        qlt_unmap_sg(vha, cmd);
        spin_unlock_irqrestore(&ha->hardware_lock, flags);

        return res;
}
EXPORT_SYMBOL(qlt_xmit_response);

int qlt_rdy_to_xfer(struct qla_tgt_cmd *cmd)
{
        struct ctio7_to_24xx *pkt;
        struct scsi_qla_host *vha = cmd->vha;
        struct qla_hw_data *ha = vha->hw;
        struct qla_tgt *tgt = cmd->tgt;
        struct qla_tgt_prm prm;
        unsigned long flags;
        int res = 0;

        memset(&prm, 0, sizeof(prm));
        prm.cmd = cmd;
        prm.tgt = tgt;
        prm.sg = NULL;
        prm.req_cnt = 1;

        /* Send marker if required */
        if (qlt_issue_marker(vha, 0) != QLA_SUCCESS)
                return -EIO;

        /* Calculate number of entries and segments required */
        if (qlt_pci_map_calc_cnt(&prm) != 0)
                return -EAGAIN;

        spin_lock_irqsave(&ha->hardware_lock, flags);

        if (!vha->flags.online || (cmd->reset_count != ha->chip_reset) ||
            (cmd->sess && cmd->sess->deleted == QLA_SESS_DELETION_IN_PROGRESS)) {
                /*
                 * Either the port is not online or this request was from
                 * previous life, just abort the processing.
                 */
                cmd->state = QLA_TGT_STATE_NEED_DATA;
                qlt_abort_cmd_on_host_reset(cmd->vha, cmd);
                ql_dbg(ql_dbg_async, vha, 0xe102,
                        "RESET-XFR online/active/old-count/new-count = %d/%d/%d/%d.\n",
                        vha->flags.online, qla2x00_reset_active(vha),
                        cmd->reset_count, ha->chip_reset);
                spin_unlock_irqrestore(&ha->hardware_lock, flags);
                return 0;
        }

        /* Does F/W have an IOCBs for this request */
        res = qlt_check_reserve_free_req(vha, prm.req_cnt);
        if (res != 0)
                goto out_unlock_free_unmap;
        if (cmd->se_cmd.prot_op)
                res = qlt_build_ctio_crc2_pkt(&prm, vha);
        else
                res = qlt_24xx_build_ctio_pkt(&prm, vha);

        if (unlikely(res != 0)) {
                vha->req->cnt += prm.req_cnt;
                goto out_unlock_free_unmap;
        }

        pkt = (struct ctio7_to_24xx *)prm.pkt;
        pkt->u.status0.flags |= cpu_to_le16(CTIO7_FLAGS_DATA_OUT |
            CTIO7_FLAGS_STATUS_MODE_0);

        if (cmd->se_cmd.prot_op == TARGET_PROT_NORMAL)
                qlt_load_data_segments(&prm, vha);

        cmd->state = QLA_TGT_STATE_NEED_DATA;
        cmd->cmd_sent_to_fw = 1;

        /* Memory Barrier */
        wmb();
        qla2x00_start_iocbs(vha, vha->req);
        spin_unlock_irqrestore(&ha->hardware_lock, flags);

        return res;

out_unlock_free_unmap:
        qlt_unmap_sg(vha, cmd);
        spin_unlock_irqrestore(&ha->hardware_lock, flags);

        return res;
}
EXPORT_SYMBOL(qlt_rdy_to_xfer);


/*
 * Checks the guard or meta-data for the type of error
 * detected by the HBA.
 */
static inline int
qlt_handle_dif_error(struct scsi_qla_host *vha, struct qla_tgt_cmd *cmd,
                struct ctio_crc_from_fw *sts)
{
        uint8_t         *ap = &sts->actual_dif[0];
        uint8_t         *ep = &sts->expected_dif[0];
        uint32_t        e_ref_tag, a_ref_tag;
        uint16_t        e_app_tag, a_app_tag;
        uint16_t        e_guard, a_guard;
        uint64_t        lba = cmd->se_cmd.t_task_lba;

        a_guard   = be16_to_cpu(*(uint16_t *)(ap + 0));
        a_app_tag = be16_to_cpu(*(uint16_t *)(ap + 2));
        a_ref_tag = be32_to_cpu(*(uint32_t *)(ap + 4));

        e_guard   = be16_to_cpu(*(uint16_t *)(ep + 0));
        e_app_tag = be16_to_cpu(*(uint16_t *)(ep + 2));
        e_ref_tag = be32_to_cpu(*(uint32_t *)(ep + 4));

        ql_dbg(ql_dbg_tgt, vha, 0xe075,
            "iocb(s) %p Returned STATUS.\n", sts);

        ql_dbg(ql_dbg_tgt, vha, 0xf075,
            "dif check TGT cdb 0x%x lba 0x%llx: [Actual|Expected] Ref Tag[0x%x|0x%x], App Tag [0x%x|0x%x], Guard [0x%x|0x%x]\n",
            cmd->atio.u.isp24.fcp_cmnd.cdb[0], lba,
            a_ref_tag, e_ref_tag, a_app_tag, e_app_tag, a_guard, e_guard);

        /*
         * Ignore sector if:
         * For type     3: ref & app tag is all 'f's
         * For type 0,1,2: app tag is all 'f's
         */
        if ((a_app_tag == 0xffff) &&
            ((cmd->se_cmd.prot_type != TARGET_DIF_TYPE3_PROT) ||
             (a_ref_tag == 0xffffffff))) {
                uint32_t blocks_done;

                /* 2TB boundary case covered automatically with this */
                blocks_done = e_ref_tag - (uint32_t)lba + 1;
                cmd->se_cmd.bad_sector = e_ref_tag;
                cmd->se_cmd.pi_err = 0;
                ql_dbg(ql_dbg_tgt, vha, 0xf074,
                        "need to return scsi good\n");

                /* Update protection tag */
                if (cmd->prot_sg_cnt) {
                        uint32_t i, k = 0, num_ent;
                        struct scatterlist *sg, *sgl;


                        sgl = cmd->prot_sg;

                        /* Patch the corresponding protection tags */
                        for_each_sg(sgl, sg, cmd->prot_sg_cnt, i) {
                                num_ent = sg_dma_len(sg) / 8;
                                if (k + num_ent < blocks_done) {
                                        k += num_ent;
                                        continue;
                                }
                                k = blocks_done;
                                break;
                        }

                        if (k != blocks_done) {
                                ql_log(ql_log_warn, vha, 0xf076,
                                    "unexpected tag values tag:lba=%u:%llu)\n",
                                    e_ref_tag, (unsigned long long)lba);
                                goto out;
                        }

#if 0
                        struct sd_dif_tuple *spt;
                        /* TODO:
                         * This section came from initiator. Is it valid here?
                         * should ulp be override with actual val???
                         */
                        spt = page_address(sg_page(sg)) + sg->offset;
                        spt += j;

                        spt->app_tag = 0xffff;
                        if (cmd->se_cmd.prot_type == SCSI_PROT_DIF_TYPE3)
                                spt->ref_tag = 0xffffffff;
#endif
                }

                return 0;
        }

        /* check guard */
        if (e_guard != a_guard) {
                cmd->se_cmd.pi_err = TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
                cmd->se_cmd.bad_sector = cmd->se_cmd.t_task_lba;