iscsi_target_util.c

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/*******************************************************************************
 * This file contains the iSCSI Target specific utility functions.
 *
 * \u00a9 Copyright 2007-2011 RisingTide Systems LLC.
 *
 * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
 *
 * Author: Nicholas A. Bellinger <[email protected]>
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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/list.h>
#include <scsi/scsi_tcq.h>
#include <scsi/iscsi_proto.h>
#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
#include <target/target_core_configfs.h>

#include "iscsi_target_core.h"
#include "iscsi_target_parameters.h"
#include "iscsi_target_seq_pdu_list.h"
#include "iscsi_target_datain_values.h"
#include "iscsi_target_erl0.h"
#include "iscsi_target_erl1.h"
#include "iscsi_target_erl2.h"
#include "iscsi_target_tpg.h"
#include "iscsi_target_tq.h"
#include "iscsi_target_util.h"
#include "iscsi_target.h"

#define PRINT_BUFF(buff, len)                   \
{                               \
    int zzz;                        \
                                \
    pr_debug("%d:\n", __LINE__);                \
    for (zzz = 0; zzz < len; zzz++) {           \
        if (zzz % 16 == 0) {                \
            if (zzz)                \
                pr_debug("\n");         \
            pr_debug("%4i: ", zzz);         \
        }                       \
        pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
    }                           \
    if ((len + 1) % 16)                 \
        pr_debug("\n");                 \
}

extern struct list_head g_tiqn_list;
extern spinlock_t tiqn_lock;

/*
 *  Called with cmd->r2t_lock held.
 */
int iscsit_add_r2t_to_list(
    struct iscsi_cmd *cmd,
    u32 offset,
    u32 xfer_len,
    int recovery,
    u32 r2t_sn)
{
    struct iscsi_r2t *r2t;

    r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
    if (!r2t) {
        pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
        return -1;
    }
    INIT_LIST_HEAD(&r2t->r2t_list);

    r2t->recovery_r2t = recovery;
    r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
    r2t->offset = offset;
    r2t->xfer_len = xfer_len;
    list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
    spin_unlock_bh(&cmd->r2t_lock);

    iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);

    spin_lock_bh(&cmd->r2t_lock);
    return 0;
}

struct iscsi_r2t *iscsit_get_r2t_for_eos(
    struct iscsi_cmd *cmd,
    u32 offset,
    u32 length)
{
    struct iscsi_r2t *r2t;

    spin_lock_bh(&cmd->r2t_lock);
    list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
        if ((r2t->offset <= offset) &&
            (r2t->offset + r2t->xfer_len) >= (offset + length)) {
            spin_unlock_bh(&cmd->r2t_lock);
            return r2t;
        }
    }
    spin_unlock_bh(&cmd->r2t_lock);

    pr_err("Unable to locate R2T for Offset: %u, Length:"
            " %u\n", offset, length);
    return NULL;
}

struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
{
    struct iscsi_r2t *r2t;

    spin_lock_bh(&cmd->r2t_lock);
    list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
        if (!r2t->sent_r2t) {
            spin_unlock_bh(&cmd->r2t_lock);
            return r2t;
        }
    }
    spin_unlock_bh(&cmd->r2t_lock);

    pr_err("Unable to locate next R2T to send for ITT:"
            " 0x%08x.\n", cmd->init_task_tag);
    return NULL;
}

/*
 *  Called with cmd->r2t_lock held.
 */
void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
{
    list_del(&r2t->r2t_list);
    kmem_cache_free(lio_r2t_cache, r2t);
}

void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
{
    struct iscsi_r2t *r2t, *r2t_tmp;

    spin_lock_bh(&cmd->r2t_lock);
    list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
        iscsit_free_r2t(r2t, cmd);
    spin_unlock_bh(&cmd->r2t_lock);
}

/*
 * May be called from software interrupt (timer) context for allocating
 * iSCSI NopINs.
 */
struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, gfp_t gfp_mask)
{
    struct iscsi_cmd *cmd;

    cmd = kmem_cache_zalloc(lio_cmd_cache, gfp_mask);
    if (!cmd) {
        pr_err("Unable to allocate memory for struct iscsi_cmd.\n");
        return NULL;
    }

    cmd->conn   = conn;
    INIT_LIST_HEAD(&cmd->i_conn_node);
    INIT_LIST_HEAD(&cmd->datain_list);
    INIT_LIST_HEAD(&cmd->cmd_r2t_list);
    init_completion(&cmd->reject_comp);
    spin_lock_init(&cmd->datain_lock);
    spin_lock_init(&cmd->dataout_timeout_lock);
    spin_lock_init(&cmd->istate_lock);
    spin_lock_init(&cmd->error_lock);
    spin_lock_init(&cmd->r2t_lock);

    return cmd;
}

struct iscsi_seq *iscsit_get_seq_holder_for_datain(
    struct iscsi_cmd *cmd,
    u32 seq_send_order)
{
    u32 i;

    for (i = 0; i < cmd->seq_count; i++)
        if (cmd->seq_list[i].seq_send_order == seq_send_order)
            return &cmd->seq_list[i];

    return NULL;
}

struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
{
    u32 i;

    if (!cmd->seq_list) {
        pr_err("struct iscsi_cmd->seq_list is NULL!\n");
        return NULL;
    }

    for (i = 0; i < cmd->seq_count; i++) {
        if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
            continue;
        if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
            cmd->seq_send_order++;
            return &cmd->seq_list[i];
        }
    }

    return NULL;
}

struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
    struct iscsi_cmd *cmd,
    u32 r2t_sn)
{
    struct iscsi_r2t *r2t;

    spin_lock_bh(&cmd->r2t_lock);
    list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
        if (r2t->r2t_sn == r2t_sn) {
            spin_unlock_bh(&cmd->r2t_lock);
            return r2t;
        }
    }
    spin_unlock_bh(&cmd->r2t_lock);

    return NULL;
}

static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
{
    int ret;

    /*
     * This is the proper method of checking received CmdSN against
     * ExpCmdSN and MaxCmdSN values, as well as accounting for out
     * or order CmdSNs due to multiple connection sessions and/or
     * CRC failures.
     */
    if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) {
        pr_err("Received CmdSN: 0x%08x is greater than"
               " MaxCmdSN: 0x%08x, protocol error.\n", cmdsn,
               sess->max_cmd_sn);
        ret = CMDSN_ERROR_CANNOT_RECOVER;

    } else if (cmdsn == sess->exp_cmd_sn) {
        sess->exp_cmd_sn++;
        pr_debug("Received CmdSN matches ExpCmdSN,"
              " incremented ExpCmdSN to: 0x%08x\n",
              sess->exp_cmd_sn);
        ret = CMDSN_NORMAL_OPERATION;

    } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
        pr_debug("Received CmdSN: 0x%08x is greater"
              " than ExpCmdSN: 0x%08x, not acknowledging.\n",
              cmdsn, sess->exp_cmd_sn);
        ret = CMDSN_HIGHER_THAN_EXP;

    } else {
        pr_err("Received CmdSN: 0x%08x is less than"
               " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
               sess->exp_cmd_sn);
        ret = CMDSN_LOWER_THAN_EXP;
    }

    return ret;
}

/*
 * Commands may be received out of order if MC/S is in use.
 * Ensure they are executed in CmdSN order.
 */
int iscsit_sequence_cmd(
    struct iscsi_conn *conn,
    struct iscsi_cmd *cmd,
    __be32 cmdsn)
{
    int ret;
    int cmdsn_ret;

    mutex_lock(&conn->sess->cmdsn_mutex);

    cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
    switch (cmdsn_ret) {
    case CMDSN_NORMAL_OPERATION:
        ret = iscsit_execute_cmd(cmd, 0);
        if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
            iscsit_execute_ooo_cmdsns(conn->sess);
        break;
    case CMDSN_HIGHER_THAN_EXP:
        ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
        break;
    case CMDSN_LOWER_THAN_EXP:
        cmd->i_state = ISTATE_REMOVE;
        iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
        ret = cmdsn_ret;
        break;
    default:
        ret = cmdsn_ret;
        break;
    }
    mutex_unlock(&conn->sess->cmdsn_mutex);

    return ret;
}

int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
{
    struct iscsi_conn *conn = cmd->conn;
    struct se_cmd *se_cmd = &cmd->se_cmd;
    struct iscsi_data *hdr = (struct iscsi_data *) buf;
    u32 payload_length = ntoh24(hdr->dlength);

    if (conn->sess->sess_ops->InitialR2T) {
        pr_err("Received unexpected unsolicited data"
            " while InitialR2T=Yes, protocol error.\n");
        transport_send_check_condition_and_sense(se_cmd,
                TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
        return -1;
    }

    if ((cmd->first_burst_len + payload_length) >
         conn->sess->sess_ops->FirstBurstLength) {
        pr_err("Total %u bytes exceeds FirstBurstLength: %u"
            " for this Unsolicited DataOut Burst.\n",
            (cmd->first_burst_len + payload_length),
                conn->sess->sess_ops->FirstBurstLength);
        transport_send_check_condition_and_sense(se_cmd,
                TCM_INCORRECT_AMOUNT_OF_DATA, 0);
        return -1;
    }

    if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
        return 0;

    if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
        ((cmd->first_burst_len + payload_length) !=
          conn->sess->sess_ops->FirstBurstLength)) {
        pr_err("Unsolicited non-immediate data received %u"
            " does not equal FirstBurstLength: %u, and does"
            " not equal ExpXferLen %u.\n",
            (cmd->first_burst_len + payload_length),
            conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
        transport_send_check_condition_and_sense(se_cmd,
                TCM_INCORRECT_AMOUNT_OF_DATA, 0);
        return -1;
    }
    return 0;
}

struct iscsi_cmd *iscsit_find_cmd_from_itt(
    struct iscsi_conn *conn,
    itt_t init_task_tag)
{
    struct iscsi_cmd *cmd;

    spin_lock_bh(&conn->cmd_lock);
    list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
        if (cmd->init_task_tag == init_task_tag) {
            spin_unlock_bh(&conn->cmd_lock);
            return cmd;
        }
    }
    spin_unlock_bh(&conn->cmd_lock);

    pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
            init_task_tag, conn->cid);
    return NULL;
}

struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
    struct iscsi_conn *conn,
    itt_t init_task_tag,
    u32 length)
{
    struct iscsi_cmd *cmd;

    spin_lock_bh(&conn->cmd_lock);
    list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
        if (cmd->init_task_tag == init_task_tag) {
            spin_unlock_bh(&conn->cmd_lock);
            return cmd;
        }
    }
    spin_unlock_bh(&conn->cmd_lock);

    pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
            " dumping payload\n", init_task_tag, conn->cid);
    if (length)
        iscsit_dump_data_payload(conn, length, 1);

    return NULL;
}

struct iscsi_cmd *iscsit_find_cmd_from_ttt(
    struct iscsi_conn *conn,
    u32 targ_xfer_tag)
{
    struct iscsi_cmd *cmd = NULL;

    spin_lock_bh(&conn->cmd_lock);
    list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
        if (cmd->targ_xfer_tag == targ_xfer_tag) {
            spin_unlock_bh(&conn->cmd_lock);
            return cmd;
        }
    }
    spin_unlock_bh(&conn->cmd_lock);

    pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
            targ_xfer_tag, conn->cid);
    return NULL;
}

int iscsit_find_cmd_for_recovery(
    struct iscsi_session *sess,
    struct iscsi_cmd **cmd_ptr,
    struct iscsi_conn_recovery **cr_ptr,
    itt_t init_task_tag)
{
    struct iscsi_cmd *cmd = NULL;
    struct iscsi_conn_recovery *cr;
    /*
     * Scan through the inactive connection recovery list's command list.
     * If init_task_tag matches the command is still alligent.
     */
    spin_lock(&sess->cr_i_lock);
    list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
        spin_lock(&cr->conn_recovery_cmd_lock);
        list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
            if (cmd->init_task_tag == init_task_tag) {
                spin_unlock(&cr->conn_recovery_cmd_lock);
                spin_unlock(&sess->cr_i_lock);

                *cr_ptr = cr;
                *cmd_ptr = cmd;
                return -2;
            }
        }
        spin_unlock(&cr->conn_recovery_cmd_lock);
    }
    spin_unlock(&sess->cr_i_lock);
    /*
     * Scan through the active connection recovery list's command list.
     * If init_task_tag matches the command is ready to be reassigned.
     */
    spin_lock(&sess->cr_a_lock);
    list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
        spin_lock(&cr->conn_recovery_cmd_lock);
        list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
            if (cmd->init_task_tag == init_task_tag) {
                spin_unlock(&cr->conn_recovery_cmd_lock);
                spin_unlock(&sess->cr_a_lock);

                *cr_ptr = cr;
                *cmd_ptr = cmd;
                return 0;
            }
        }
        spin_unlock(&cr->conn_recovery_cmd_lock);
    }
    spin_unlock(&sess->cr_a_lock);

    return -1;
}

void iscsit_add_cmd_to_immediate_queue(
    struct iscsi_cmd *cmd,
    struct iscsi_conn *conn,
    u8 state)
{
    struct iscsi_queue_req *qr;

    qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
    if (!qr) {
        pr_err("Unable to allocate memory for"
                " struct iscsi_queue_req\n");
        return;
    }
    INIT_LIST_HEAD(&qr->qr_list);
    qr->cmd = cmd;
    qr->state = state;

    spin_lock_bh(&conn->immed_queue_lock);
    list_add_tail(&qr->qr_list, &conn->immed_queue_list);
    atomic_inc(&cmd->immed_queue_count);
    atomic_set(&conn->check_immediate_queue, 1);
    spin_unlock_bh(&conn->immed_queue_lock);

    wake_up(&conn->queues_wq);
}

struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
{
    struct iscsi_queue_req *qr;

    spin_lock_bh(&conn->immed_queue_lock);
    if (list_empty(&conn->immed_queue_list)) {
        spin_unlock_bh(&conn->immed_queue_lock);
        return NULL;
    }
    list_for_each_entry(qr, &conn->immed_queue_list, qr_list)
        break;

    list_del(&qr->qr_list);
    if (qr->cmd)
        atomic_dec(&qr->cmd->immed_queue_count);
    spin_unlock_bh(&conn->immed_queue_lock);

    return qr;
}

static void iscsit_remove_cmd_from_immediate_queue(
    struct iscsi_cmd *cmd,
    struct iscsi_conn *conn)
{
    struct iscsi_queue_req *qr, *qr_tmp;

    spin_lock_bh(&conn->immed_queue_lock);
    if (!atomic_read(&cmd->immed_queue_count)) {
        spin_unlock_bh(&conn->immed_queue_lock);
        return;
    }

    list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
        if (qr->cmd != cmd)
            continue;

        atomic_dec(&qr->cmd->immed_queue_count);
        list_del(&qr->qr_list);
        kmem_cache_free(lio_qr_cache, qr);
    }
    spin_unlock_bh(&conn->immed_queue_lock);

    if (atomic_read(&cmd->immed_queue_count)) {
        pr_err("ITT: 0x%08x immed_queue_count: %d\n",
            cmd->init_task_tag,
            atomic_read(&cmd->immed_queue_count));
    }
}

void iscsit_add_cmd_to_response_queue(
    struct iscsi_cmd *cmd,
    struct iscsi_conn *conn,
    u8 state)
{
    struct iscsi_queue_req *qr;

    qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
    if (!qr) {
        pr_err("Unable to allocate memory for"
            " struct iscsi_queue_req\n");
        return;
    }
    INIT_LIST_HEAD(&qr->qr_list);
    qr->cmd = cmd;
    qr->state = state;

    spin_lock_bh(&conn->response_queue_lock);
    list_add_tail(&qr->qr_list, &conn->response_queue_list);
    atomic_inc(&cmd->response_queue_count);
    spin_unlock_bh(&conn->response_queue_lock);

    wake_up(&conn->queues_wq);
}

struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
{
    struct iscsi_queue_req *qr;

    spin_lock_bh(&conn->response_queue_lock);
    if (list_empty(&conn->response_queue_list)) {
        spin_unlock_bh(&conn->response_queue_lock);
        return NULL;
    }

    list_for_each_entry(qr, &conn->response_queue_list, qr_list)
        break;

    list_del(&qr->qr_list);
    if (qr->cmd)
        atomic_dec(&qr->cmd->response_queue_count);
    spin_unlock_bh(&conn->response_queue_lock);

    return qr;
}

static void iscsit_remove_cmd_from_response_queue(
    struct iscsi_cmd *cmd,
    struct iscsi_conn *conn)
{
    struct iscsi_queue_req *qr, *qr_tmp;

    spin_lock_bh(&conn->response_queue_lock);
    if (!atomic_read(&cmd->response_queue_count)) {
        spin_unlock_bh(&conn->response_queue_lock);
        return;
    }

    list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
                qr_list) {
        if (qr->cmd != cmd)
            continue;

        atomic_dec(&qr->cmd->response_queue_count);
        list_del(&qr->qr_list);
        kmem_cache_free(lio_qr_cache, qr);
    }
    spin_unlock_bh(&conn->response_queue_lock);

    if (atomic_read(&cmd->response_queue_count)) {
        pr_err("ITT: 0x%08x response_queue_count: %d\n",
            cmd->init_task_tag,
            atomic_read(&cmd->response_queue_count));
    }
}

bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
{
    bool empty;

    spin_lock_bh(&conn->immed_queue_lock);
    empty = list_empty(&conn->immed_queue_list);
    spin_unlock_bh(&conn->immed_queue_lock);

    if (!empty)
        return empty;

    spin_lock_bh(&conn->response_queue_lock);
    empty = list_empty(&conn->response_queue_list);
    spin_unlock_bh(&conn->response_queue_lock);

    return empty;
}

void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
{
    struct iscsi_queue_req *qr, *qr_tmp;

    spin_lock_bh(&conn->immed_queue_lock);
    list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
        list_del(&qr->qr_list);
        if (qr->cmd)
            atomic_dec(&qr->cmd->immed_queue_count);

        kmem_cache_free(lio_qr_cache, qr);
    }
    spin_unlock_bh(&conn->immed_queue_lock);

    spin_lock_bh(&conn->response_queue_lock);
    list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
            qr_list) {
        list_del(&qr->qr_list);
        if (qr->cmd)
            atomic_dec(&qr->cmd->response_queue_count);

        kmem_cache_free(lio_qr_cache, qr);
    }
    spin_unlock_bh(&conn->response_queue_lock);
}

void iscsit_release_cmd(struct iscsi_cmd *cmd)
{
    struct iscsi_conn *conn = cmd->conn;

    iscsit_free_r2ts_from_list(cmd);
    iscsit_free_all_datain_reqs(cmd);

    kfree(cmd->buf_ptr);
    kfree(cmd->pdu_list);
    kfree(cmd->seq_list);
    kfree(cmd->tmr_req);
    kfree(cmd->iov_data);

    if (conn) {
        iscsit_remove_cmd_from_immediate_queue(cmd, conn);
        iscsit_remove_cmd_from_response_queue(cmd, conn);
    }

    kmem_cache_free(lio_cmd_cache, cmd);
}

void iscsit_free_cmd(struct iscsi_cmd *cmd)
{
    /*
     * Determine if a struct se_cmd is assoicated with
     * this struct iscsi_cmd.
     */
    switch (cmd->iscsi_opcode) {
    case ISCSI_OP_SCSI_CMD:
    case ISCSI_OP_SCSI_TMFUNC:
        transport_generic_free_cmd(&cmd->se_cmd, 1);
        break;
    case ISCSI_OP_REJECT:
        /*
         * Handle special case for REJECT when iscsi_add_reject*() has
         * overwritten the original iscsi_opcode assignment, and the
         * associated cmd->se_cmd needs to be released.
         */
        if (cmd->se_cmd.se_tfo != NULL) {
            transport_generic_free_cmd(&cmd->se_cmd, 1);
            break;
        }
        /* Fall-through */
    default:
        iscsit_release_cmd(cmd);
        break;
    }
}

int iscsit_check_session_usage_count(struct iscsi_session *sess)
{
    spin_lock_bh(&sess->session_usage_lock);
    if (sess->session_usage_count != 0) {
        sess->session_waiting_on_uc = 1;
        spin_unlock_bh(&sess->session_usage_lock);
        if (in_interrupt())
            return 2;

        wait_for_completion(&sess->session_waiting_on_uc_comp);
        return 1;
    }
    spin_unlock_bh(&sess->session_usage_lock);

    return 0;
}

void iscsit_dec_session_usage_count(struct iscsi_session *sess)
{
    spin_lock_bh(&sess->session_usage_lock);
    sess->session_usage_count--;

    if (!sess->session_usage_count && sess->session_waiting_on_uc)
        complete(&sess->session_waiting_on_uc_comp);

    spin_unlock_bh(&sess->session_usage_lock);
}

void iscsit_inc_session_usage_count(struct iscsi_session *sess)
{
    spin_lock_bh(&sess->session_usage_lock);
    sess->session_usage_count++;
    spin_unlock_bh(&sess->session_usage_lock);
}

/*
 *  Setup conn->if_marker and conn->of_marker values based upon
 *  the initial marker-less interval. (see iSCSI v19 A.2)
 */
int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
{
    int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
    /*
     * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
     */
    u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
    u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);

    if (conn->conn_ops->OFMarker) {
        /*
         * Account for the first Login Command received not
         * via iscsi_recv_msg().
         */
        conn->of_marker += ISCSI_HDR_LEN;
        if (conn->of_marker <= OFMarkInt) {
            conn->of_marker = (OFMarkInt - conn->of_marker);
        } else {
            login_ofmarker_count = (conn->of_marker / OFMarkInt);
            next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
                    (login_ofmarker_count * MARKER_SIZE);
            conn->of_marker = (next_marker - conn->of_marker);
        }
        conn->of_marker_offset = 0;
        pr_debug("Setting OFMarker value to %u based on Initial"
            " Markerless Interval.\n", conn->of_marker);
    }

    if (conn->conn_ops->IFMarker) {
        if (conn->if_marker <= IFMarkInt) {
            conn->if_marker = (IFMarkInt - conn->if_marker);
        } else {
            login_ifmarker_count = (conn->if_marker / IFMarkInt);
            next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
                    (login_ifmarker_count * MARKER_SIZE);
            conn->if_marker = (next_marker - conn->if_marker);
        }
        pr_debug("Setting IFMarker value to %u based on Initial"
            " Markerless Interval.\n", conn->if_marker);
    }

    return 0;
}

struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
{
    struct iscsi_conn *conn;

    spin_lock_bh(&sess->conn_lock);
    list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
        if ((conn->cid == cid) &&
            (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
            iscsit_inc_conn_usage_count(conn);
            spin_unlock_bh(&sess->conn_lock);
            return conn;
        }
    }
    spin_unlock_bh(&sess->conn_lock);

    return NULL;
}

struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
{
    struct iscsi_conn *conn;

    spin_lock_bh(&sess->conn_lock);
    list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
        if (conn->cid == cid) {
            iscsit_inc_conn_usage_count(conn);
            spin_lock(&conn->state_lock);
            atomic_set(&conn->connection_wait_rcfr, 1);
            spin_unlock(&conn->state_lock);
            spin_unlock_bh(&sess->conn_lock);
            return conn;
        }
    }
    spin_unlock_bh(&sess->conn_lock);

    return NULL;
}

void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
{
    spin_lock_bh(&conn->conn_usage_lock);
    if (conn->conn_usage_count != 0) {
        conn->conn_waiting_on_uc = 1;
        spin_unlock_bh(&conn->conn_usage_lock);

        wait_for_completion(&conn->conn_waiting_on_uc_comp);
        return;
    }
    spin_unlock_bh(&conn->conn_usage_lock);
}

void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
{
    spin_lock_bh(&conn->conn_usage_lock);
    conn->conn_usage_count--;

    if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
        complete(&conn->conn_waiting_on_uc_comp);

    spin_unlock_bh(&conn->conn_usage_lock);
}

void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
{
    spin_lock_bh(&conn->conn_usage_lock);
    conn->conn_usage_count++;
    spin_unlock_bh(&conn->conn_usage_lock);
}

static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
{
    u8 state;
    struct iscsi_cmd *cmd;

    cmd = iscsit_allocate_cmd(conn, GFP_ATOMIC);
    if (!cmd)
        return -1;

    cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
    state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
                ISTATE_SEND_NOPIN_NO_RESPONSE;
    cmd->init_task_tag = RESERVED_ITT;
    spin_lock_bh(&conn->sess->ttt_lock);
    cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
            0xFFFFFFFF;
    if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
        cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
    spin_unlock_bh(&conn->sess->ttt_lock);

    spin_lock_bh(&conn->cmd_lock);
    list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
    spin_unlock_bh(&conn->cmd_lock);

    if (want_response)
        iscsit_start_nopin_response_timer(conn);
    iscsit_add_cmd_to_immediate_queue(cmd, conn, state);

    return 0;
}

static void iscsit_handle_nopin_response_timeout(unsigned long data)
{
    struct iscsi_conn *conn = (struct iscsi_conn *) data;

    iscsit_inc_conn_usage_count(conn);

    spin_lock_bh(&conn->nopin_timer_lock);
    if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
        spin_unlock_bh(&conn->nopin_timer_lock);
        iscsit_dec_conn_usage_count(conn);
        return;
    }

    pr_debug("Did not receive response to NOPIN on CID: %hu on"
        " SID: %u, failing connection.\n", conn->cid,
            conn->sess->sid);
    conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
    spin_unlock_bh(&conn->nopin_timer_lock);

    {
    struct iscsi_portal_group *tpg = conn->sess->tpg;
    struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;

    if (tiqn) {
        spin_lock_bh(&tiqn->sess_err_stats.lock);
        strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
                conn->sess->sess_ops->InitiatorName);
        tiqn->sess_err_stats.last_sess_failure_type =
                ISCSI_SESS_ERR_CXN_TIMEOUT;
        tiqn->sess_err_stats.cxn_timeout_errors++;
        conn->sess->conn_timeout_errors++;
        spin_unlock_bh(&tiqn->sess_err_stats.lock);
    }
    }

    iscsit_cause_connection_reinstatement(conn, 0);
    iscsit_dec_conn_usage_count(conn);
}

void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
{
    struct iscsi_session *sess = conn->sess;
    struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);

    spin_lock_bh(&conn->nopin_timer_lock);
    if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
        spin_unlock_bh(&conn->nopin_timer_lock);
        return;
    }

    mod_timer(&conn->nopin_response_timer,
        (get_jiffies_64() + na->nopin_response_timeout * HZ));
    spin_unlock_bh(&conn->nopin_timer_lock);
}

/*
 *  Called with conn->nopin_timer_lock held.
 */
void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
{
    struct iscsi_session *sess = conn->sess;
    struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);

    spin_lock_bh(&conn->nopin_timer_lock);
    if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
        spin_unlock_bh(&conn->nopin_timer_lock);
        return;
    }

    init_timer(&conn->nopin_response_timer);
    conn->nopin_response_timer.expires =
        (get_jiffies_64() + na->nopin_response_timeout * HZ);
    conn->nopin_response_timer.data = (unsigned long)conn;
    conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
    conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
    conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
    add_timer(&conn->nopin_response_timer);

    pr_debug("Started NOPIN Response Timer on CID: %d to %u"
        " seconds\n", conn->cid, na->nopin_response_timeout);
    spin_unlock_bh(&conn->nopin_timer_lock);
}

void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
{
    spin_lock_bh(&conn->nopin_timer_lock);
    if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
        spin_unlock_bh(&conn->nopin_timer_lock);
        return;
    }
    conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
    spin_unlock_bh(&conn->nopin_timer_lock);

    del_timer_sync(&conn->nopin_response_timer);

    spin_lock_bh(&conn->nopin_timer_lock);
    conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
    spin_unlock_bh(&conn->nopin_timer_lock);
}

static void iscsit_handle_nopin_timeout(unsigned long data)
{
    struct iscsi_conn *conn = (struct iscsi_conn *) data;

    iscsit_inc_conn_usage_count(conn);

    spin_lock_bh(&conn->nopin_timer_lock);
    if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
        spin_unlock_bh(&conn->nopin_timer_lock);
        iscsit_dec_conn_usage_count(conn);
        return;
    }
    conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
    spin_unlock_bh(&conn->nopin_timer_lock);

    iscsit_add_nopin(conn, 1);
    iscsit_dec_conn_usage_count(conn);
}

/*
 * Called with conn->nopin_timer_lock held.
 */
void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
{
    struct iscsi_session *sess = conn->sess;
    struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
    /*
    * NOPIN timeout is disabled.
     */
    if (!na->nopin_timeout)
        return;

    if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
        return;

    init_timer(&conn->nopin_timer);
    conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
    conn->nopin_timer.data = (unsigned long)conn;
    conn->nopin_timer.function = iscsit_handle_nopin_timeout;
    conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
    conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
    add_timer(&conn->nopin_timer);

    pr_debug("Started NOPIN Timer on CID: %d at %u second"
        " interval\n", conn->cid, na->nopin_timeout);
}

void iscsit_start_nopin_timer(struct iscsi_conn *conn)
{
    struct iscsi_session *sess = conn->sess;
    struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
    /*
     * NOPIN timeout is disabled..
     */
    if (!na->nopin_timeout)
        return;

    spin_lock_bh(&conn->nopin_timer_lock);
    if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
        spin_unlock_bh(&conn->nopin_timer_lock);
        return;
    }

    init_timer(&conn->nopin_timer);
    conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
    conn->nopin_timer.data = (unsigned long)conn;
    conn->nopin_timer.function = iscsit_handle_nopin_timeout;
    conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
    conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
    add_timer(&conn->nopin_timer);

    pr_debug("Started NOPIN Timer on CID: %d at %u second"
            " interval\n", conn->cid, na->nopin_timeout);
    spin_unlock_bh(&conn->nopin_timer_lock);
}

void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
{
    spin_lock_bh(&conn->nopin_timer_lock);
    if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
        spin_unlock_bh(&conn->nopin_timer_lock);
        return;
    }
    conn->nopin_timer_flags |= ISCSI_TF_STOP;
    spin_unlock_bh(&conn->nopin_timer_lock);

    del_timer_sync(&conn->nopin_timer);

    spin_lock_bh(&conn->nopin_timer_lock);
    conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
    spin_unlock_bh(&conn->nopin_timer_lock);
}

int iscsit_send_tx_data(
    struct iscsi_cmd *cmd,
    struct iscsi_conn *conn,
    int use_misc)
{
    int tx_sent, tx_size;
    u32 iov_count;
    struct kvec *iov;

send_data:
    tx_size = cmd->tx_size;

    if (!use_misc) {
        iov = &cmd->iov_data[0];
        iov_count = cmd->iov_data_count;
    } else {
        iov = &cmd->iov_misc[0];
        iov_count = cmd->iov_misc_count;
    }

    tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
    if (tx_size != tx_sent) {
        if (tx_sent == -EAGAIN) {
            pr_err("tx_data() returned -EAGAIN\n");
            goto send_data;
        } else
            return -1;
    }
    cmd->tx_size = 0;

    return 0;
}

int iscsit_fe_sendpage_sg(
    struct iscsi_cmd *cmd,
    struct iscsi_conn *conn)
{
    struct scatterlist *sg = cmd->first_data_sg;
    struct kvec iov;
    u32 tx_hdr_size, data_len;
    u32 offset = cmd->first_data_sg_off;
    int tx_sent, iov_off;

send_hdr:
    tx_hdr_size = ISCSI_HDR_LEN;
    if (conn->conn_ops->HeaderDigest)
        tx_hdr_size += ISCSI_CRC_LEN;

    iov.iov_base = cmd->pdu;
    iov.iov_len = tx_hdr_size;

    tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
    if (tx_hdr_size != tx_sent) {
        if (tx_sent == -EAGAIN) {
            pr_err("tx_data() returned -EAGAIN\n");
            goto send_hdr;
        }
        return -1;
    }

    data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
    /*
     * Set iov_off used by padding and data digest tx_data() calls below
     * in order to determine proper offset into cmd->iov_data[]
     */
    if (conn->conn_ops->DataDigest) {
        data_len -= ISCSI_CRC_LEN;
        if (cmd->padding)
            iov_off = (cmd->iov_data_count - 2);
        else
            iov_off = (cmd->iov_data_count - 1);
    } else {
        iov_off = (cmd->iov_data_count - 1);
    }
    /*
     * Perform sendpage() for each page in the scatterlist
     */
    while (data_len) {
        u32 space = (sg->length - offset);
        u32 sub_len = min_t(u32, data_len, space);
send_pg:
        tx_sent = conn->sock->ops->sendpage(conn->sock,
                    sg_page(sg), sg->offset + offset, sub_len, 0);
        if (tx_sent != sub_len) {
            if (tx_sent == -EAGAIN) {
                pr_err("tcp_sendpage() returned"
                        " -EAGAIN\n");
                goto send_pg;
            }

            pr_err("tcp_sendpage() failure: %d\n",
                    tx_sent);
            return -1;
        }

        data_len -= sub_len;
        offset = 0;
        sg = sg_next(sg);
    }

send_padding:
    if (cmd->padding) {
        struct kvec *iov_p = &cmd->iov_data[iov_off++];

        tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
        if (cmd->padding != tx_sent) {
            if (tx_sent == -EAGAIN) {
                pr_err("tx_data() returned -EAGAIN\n");
                goto send_padding;
            }
            return -1;
        }
    }

send_datacrc:
    if (conn->conn_ops->DataDigest) {
        struct kvec *iov_d = &cmd->iov_data[iov_off];

        tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
        if (ISCSI_CRC_LEN != tx_sent) {
            if (tx_sent == -EAGAIN) {
                pr_err("tx_data() returned -EAGAIN\n");
                goto send_datacrc;
            }
            return -1;
        }
    }

    return 0;
}

/*
 *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
 *      back to the Initiator when an expection condition occurs with the
 *      errors set in status_class and status_detail.
 *
 *      Parameters:     iSCSI Connection, Status Class, Status Detail.
 *      Returns:        0 on success, -1 on error.
 */
int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
{
    u8 iscsi_hdr[ISCSI_HDR_LEN];
    int err;
    struct kvec iov;
    struct iscsi_login_rsp *hdr;

    iscsit_collect_login_stats(conn, status_class, status_detail);

    memset(&iov, 0, sizeof(struct kvec));
    memset(&iscsi_hdr, 0x0, ISCSI_HDR_LEN);

    hdr = (struct iscsi_login_rsp *)&iscsi_hdr;
    hdr->opcode     = ISCSI_OP_LOGIN_RSP;
    hdr->status_class   = status_class;
    hdr->status_detail  = status_detail;
    hdr->itt        = conn->login_itt;

    iov.iov_base        = &iscsi_hdr;
    iov.iov_len     = ISCSI_HDR_LEN;

    PRINT_BUFF(iscsi_hdr, ISCSI_HDR_LEN);

    err = tx_data(conn, &iov, 1, ISCSI_HDR_LEN);
    if (err != ISCSI_HDR_LEN) {
        pr_err("tx_data returned less than expected\n");
        return -1;
    }

    return 0;
}

void iscsit_print_session_params(struct iscsi_session *sess)
{
    struct iscsi_conn *conn;

    pr_debug("-----------------------------[Session Params for"
        " SID: %u]-----------------------------\n", sess->sid);
    spin_lock_bh(&sess->conn_lock);
    list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
        iscsi_dump_conn_ops(conn->conn_ops);
    spin_unlock_bh(&sess->conn_lock);

    iscsi_dump_sess_ops(sess->sess_ops);
}

static int iscsit_do_rx_data(
    struct iscsi_conn *conn,
    struct iscsi_data_count *count)
{
    int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
    struct kvec *iov_p;
    struct msghdr msg;

    if (!conn || !conn->sock || !conn->conn_ops)
        return -1;

    memset(&msg, 0, sizeof(struct msghdr));

    iov_p = count->iov;
    iov_len = count->iov_count;

    while (total_rx < data) {
        rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
                    (data - total_rx), MSG_WAITALL);
        if (rx_loop <= 0) {
            pr_debug("rx_loop: %d total_rx: %d\n",
                rx_loop, total_rx);
            return rx_loop;
        }
        total_rx += rx_loop;
        pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
                rx_loop, total_rx, data);
    }

    return total_rx;
}

static int iscsit_do_tx_data(
    struct iscsi_conn *conn,
    struct iscsi_data_count *count)
{
    int data = count->data_length, total_tx = 0, tx_loop = 0, iov_len;
    struct kvec *iov_p;
    struct msghdr msg;

    if (!conn || !conn->sock || !conn->conn_ops)
        return -1;

    if (data <= 0) {
        pr_err("Data length is: %d\n", data);
        return -1;
    }

    memset(&msg, 0, sizeof(struct msghdr));

    iov_p = count->iov;
    iov_len = count->iov_count;

    while (total_tx < data) {
        tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
                    (data - total_tx));
        if (tx_loop <= 0) {
            pr_debug("tx_loop: %d total_tx %d\n",
                tx_loop, total_tx);
            return tx_loop;
        }
        total_tx += tx_loop;
        pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
                    tx_loop, total_tx, data);
    }

    return total_tx;
}

int rx_data(
    struct iscsi_conn *conn,
    struct kvec *iov,
    int iov_count,
    int data)
{
    struct iscsi_data_count c;

    if (!conn || !conn->sock || !conn->conn_ops)
        return -1;

    memset(&c, 0, sizeof(struct iscsi_data_count));
    c.iov = iov;
    c.iov_count = iov_count;
    c.data_length = data;
    c.type = ISCSI_RX_DATA;

    return iscsit_do_rx_data(conn, &c);
}

int tx_data(
    struct iscsi_conn *conn,
    struct kvec *iov,
    int iov_count,
    int data)
{
    struct iscsi_data_count c;

    if (!conn || !conn->sock || !conn->conn_ops)
        return -1;

    memset(&c, 0, sizeof(struct iscsi_data_count));
    c.iov = iov;
    c.iov_count = iov_count;
    c.data_length = data;
    c.type = ISCSI_TX_DATA;

    return iscsit_do_tx_data(conn, &c);
}

void iscsit_collect_login_stats(
    struct iscsi_conn *conn,
    u8 status_class,
    u8 status_detail)
{
    struct iscsi_param *intrname = NULL;
    struct iscsi_tiqn *tiqn;
    struct iscsi_login_stats *ls;

    tiqn = iscsit_snmp_get_tiqn(conn);
    if (!tiqn)
        return;

    ls = &tiqn->login_stats;

    spin_lock(&ls->lock);
    if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
        ((get_jiffies_64() - ls->last_fail_time) < 10)) {
        /* We already have the failure info for this login */
        spin_unlock(&ls->lock);
        return;
    }

    if (status_class == ISCSI_STATUS_CLS_SUCCESS)
        ls->accepts++;
    else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
        ls->redirects++;
        ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
    } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
         (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
        ls->authenticate_fails++;
        ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
    } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
         (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
        ls->authorize_fails++;
        ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
    } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
         (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
        ls->negotiate_fails++;
        ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
    } else {
        ls->other_fails++;
        ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
    }

    /* Save initiator name, ip address and time, if it is a failed login */
    if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
        if (conn->param_list)
            intrname = iscsi_find_param_from_key(INITIATORNAME,
                                 conn->param_list);
        strcpy(ls->last_intr_fail_name,
               (intrname ? intrname->value : "Unknown"));

        ls->last_intr_fail_ip_family = conn->sock->sk->sk_family;
        snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
                "%s", conn->login_ip);
        ls->last_fail_time = get_jiffies_64();
    }

    spin_unlock(&ls->lock);
}

struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
{
    struct iscsi_portal_group *tpg;

    if (!conn || !conn->sess)
        return NULL;

    tpg = conn->sess->tpg;
    if (!tpg)
        return NULL;

    if (!tpg->tpg_tiqn)
        return NULL;

    return tpg->tpg_tiqn;
}