linux/drivers/target/iscsi/iscsi_target_util.c
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   1/*******************************************************************************
   2 * This file contains the iSCSI Target specific utility functions.
   3 *
   4 * (c) Copyright 2007-2013 Datera, Inc.
   5 *
   6 * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License as published by
  10 * the Free Software Foundation; either version 2 of the License, or
  11 * (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 ******************************************************************************/
  18
  19#include <linux/list.h>
  20#include <linux/percpu_ida.h>
  21#include <scsi/scsi_tcq.h>
  22#include <scsi/iscsi_proto.h>
  23#include <target/target_core_base.h>
  24#include <target/target_core_fabric.h>
  25#include <target/target_core_configfs.h>
  26#include <target/iscsi/iscsi_transport.h>
  27
  28#include <target/iscsi/iscsi_target_core.h>
  29#include "iscsi_target_parameters.h"
  30#include "iscsi_target_seq_pdu_list.h"
  31#include "iscsi_target_datain_values.h"
  32#include "iscsi_target_erl0.h"
  33#include "iscsi_target_erl1.h"
  34#include "iscsi_target_erl2.h"
  35#include "iscsi_target_tpg.h"
  36#include "iscsi_target_util.h"
  37#include "iscsi_target.h"
  38
  39#define PRINT_BUFF(buff, len)                                   \
  40{                                                               \
  41        int zzz;                                                \
  42                                                                \
  43        pr_debug("%d:\n", __LINE__);                            \
  44        for (zzz = 0; zzz < len; zzz++) {                       \
  45                if (zzz % 16 == 0) {                            \
  46                        if (zzz)                                \
  47                                pr_debug("\n");                 \
  48                        pr_debug("%4i: ", zzz);                 \
  49                }                                               \
  50                pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  51        }                                                       \
  52        if ((len + 1) % 16)                                     \
  53                pr_debug("\n");                                 \
  54}
  55
  56extern struct list_head g_tiqn_list;
  57extern spinlock_t tiqn_lock;
  58
  59/*
  60 *      Called with cmd->r2t_lock held.
  61 */
  62int iscsit_add_r2t_to_list(
  63        struct iscsi_cmd *cmd,
  64        u32 offset,
  65        u32 xfer_len,
  66        int recovery,
  67        u32 r2t_sn)
  68{
  69        struct iscsi_r2t *r2t;
  70
  71        r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  72        if (!r2t) {
  73                pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  74                return -1;
  75        }
  76        INIT_LIST_HEAD(&r2t->r2t_list);
  77
  78        r2t->recovery_r2t = recovery;
  79        r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  80        r2t->offset = offset;
  81        r2t->xfer_len = xfer_len;
  82        list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  83        spin_unlock_bh(&cmd->r2t_lock);
  84
  85        iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  86
  87        spin_lock_bh(&cmd->r2t_lock);
  88        return 0;
  89}
  90
  91struct iscsi_r2t *iscsit_get_r2t_for_eos(
  92        struct iscsi_cmd *cmd,
  93        u32 offset,
  94        u32 length)
  95{
  96        struct iscsi_r2t *r2t;
  97
  98        spin_lock_bh(&cmd->r2t_lock);
  99        list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 100                if ((r2t->offset <= offset) &&
 101                    (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 102                        spin_unlock_bh(&cmd->r2t_lock);
 103                        return r2t;
 104                }
 105        }
 106        spin_unlock_bh(&cmd->r2t_lock);
 107
 108        pr_err("Unable to locate R2T for Offset: %u, Length:"
 109                        " %u\n", offset, length);
 110        return NULL;
 111}
 112
 113struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 114{
 115        struct iscsi_r2t *r2t;
 116
 117        spin_lock_bh(&cmd->r2t_lock);
 118        list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 119                if (!r2t->sent_r2t) {
 120                        spin_unlock_bh(&cmd->r2t_lock);
 121                        return r2t;
 122                }
 123        }
 124        spin_unlock_bh(&cmd->r2t_lock);
 125
 126        pr_err("Unable to locate next R2T to send for ITT:"
 127                        " 0x%08x.\n", cmd->init_task_tag);
 128        return NULL;
 129}
 130
 131/*
 132 *      Called with cmd->r2t_lock held.
 133 */
 134void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 135{
 136        list_del(&r2t->r2t_list);
 137        kmem_cache_free(lio_r2t_cache, r2t);
 138}
 139
 140void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 141{
 142        struct iscsi_r2t *r2t, *r2t_tmp;
 143
 144        spin_lock_bh(&cmd->r2t_lock);
 145        list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 146                iscsit_free_r2t(r2t, cmd);
 147        spin_unlock_bh(&cmd->r2t_lock);
 148}
 149
 150/*
 151 * May be called from software interrupt (timer) context for allocating
 152 * iSCSI NopINs.
 153 */
 154struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, int state)
 155{
 156        struct iscsi_cmd *cmd;
 157        struct se_session *se_sess = conn->sess->se_sess;
 158        int size, tag;
 159
 160        tag = percpu_ida_alloc(&se_sess->sess_tag_pool, state);
 161        if (tag < 0)
 162                return NULL;
 163
 164        size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
 165        cmd = (struct iscsi_cmd *)(se_sess->sess_cmd_map + (tag * size));
 166        memset(cmd, 0, size);
 167
 168        cmd->se_cmd.map_tag = tag;
 169        cmd->conn = conn;
 170        INIT_LIST_HEAD(&cmd->i_conn_node);
 171        INIT_LIST_HEAD(&cmd->datain_list);
 172        INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 173        spin_lock_init(&cmd->datain_lock);
 174        spin_lock_init(&cmd->dataout_timeout_lock);
 175        spin_lock_init(&cmd->istate_lock);
 176        spin_lock_init(&cmd->error_lock);
 177        spin_lock_init(&cmd->r2t_lock);
 178
 179        return cmd;
 180}
 181EXPORT_SYMBOL(iscsit_allocate_cmd);
 182
 183struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 184        struct iscsi_cmd *cmd,
 185        u32 seq_send_order)
 186{
 187        u32 i;
 188
 189        for (i = 0; i < cmd->seq_count; i++)
 190                if (cmd->seq_list[i].seq_send_order == seq_send_order)
 191                        return &cmd->seq_list[i];
 192
 193        return NULL;
 194}
 195
 196struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 197{
 198        u32 i;
 199
 200        if (!cmd->seq_list) {
 201                pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 202                return NULL;
 203        }
 204
 205        for (i = 0; i < cmd->seq_count; i++) {
 206                if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 207                        continue;
 208                if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 209                        cmd->seq_send_order++;
 210                        return &cmd->seq_list[i];
 211                }
 212        }
 213
 214        return NULL;
 215}
 216
 217struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 218        struct iscsi_cmd *cmd,
 219        u32 r2t_sn)
 220{
 221        struct iscsi_r2t *r2t;
 222
 223        spin_lock_bh(&cmd->r2t_lock);
 224        list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 225                if (r2t->r2t_sn == r2t_sn) {
 226                        spin_unlock_bh(&cmd->r2t_lock);
 227                        return r2t;
 228                }
 229        }
 230        spin_unlock_bh(&cmd->r2t_lock);
 231
 232        return NULL;
 233}
 234
 235static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 236{
 237        int ret;
 238
 239        /*
 240         * This is the proper method of checking received CmdSN against
 241         * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 242         * or order CmdSNs due to multiple connection sessions and/or
 243         * CRC failures.
 244         */
 245        if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) {
 246                pr_err("Received CmdSN: 0x%08x is greater than"
 247                       " MaxCmdSN: 0x%08x, ignoring.\n", cmdsn,
 248                       sess->max_cmd_sn);
 249                ret = CMDSN_MAXCMDSN_OVERRUN;
 250
 251        } else if (cmdsn == sess->exp_cmd_sn) {
 252                sess->exp_cmd_sn++;
 253                pr_debug("Received CmdSN matches ExpCmdSN,"
 254                      " incremented ExpCmdSN to: 0x%08x\n",
 255                      sess->exp_cmd_sn);
 256                ret = CMDSN_NORMAL_OPERATION;
 257
 258        } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 259                pr_debug("Received CmdSN: 0x%08x is greater"
 260                      " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 261                      cmdsn, sess->exp_cmd_sn);
 262                ret = CMDSN_HIGHER_THAN_EXP;
 263
 264        } else {
 265                pr_err("Received CmdSN: 0x%08x is less than"
 266                       " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 267                       sess->exp_cmd_sn);
 268                ret = CMDSN_LOWER_THAN_EXP;
 269        }
 270
 271        return ret;
 272}
 273
 274/*
 275 * Commands may be received out of order if MC/S is in use.
 276 * Ensure they are executed in CmdSN order.
 277 */
 278int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 279                        unsigned char *buf, __be32 cmdsn)
 280{
 281        int ret, cmdsn_ret;
 282        bool reject = false;
 283        u8 reason = ISCSI_REASON_BOOKMARK_NO_RESOURCES;
 284
 285        mutex_lock(&conn->sess->cmdsn_mutex);
 286
 287        cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
 288        switch (cmdsn_ret) {
 289        case CMDSN_NORMAL_OPERATION:
 290                ret = iscsit_execute_cmd(cmd, 0);
 291                if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 292                        iscsit_execute_ooo_cmdsns(conn->sess);
 293                else if (ret < 0) {
 294                        reject = true;
 295                        ret = CMDSN_ERROR_CANNOT_RECOVER;
 296                }
 297                break;
 298        case CMDSN_HIGHER_THAN_EXP:
 299                ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
 300                if (ret < 0) {
 301                        reject = true;
 302                        ret = CMDSN_ERROR_CANNOT_RECOVER;
 303                        break;
 304                }
 305                ret = CMDSN_HIGHER_THAN_EXP;
 306                break;
 307        case CMDSN_LOWER_THAN_EXP:
 308        case CMDSN_MAXCMDSN_OVERRUN:
 309        default:
 310                cmd->i_state = ISTATE_REMOVE;
 311                iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 312                /*
 313                 * Existing callers for iscsit_sequence_cmd() will silently
 314                 * ignore commands with CMDSN_LOWER_THAN_EXP, so force this
 315                 * return for CMDSN_MAXCMDSN_OVERRUN as well..
 316                 */
 317                ret = CMDSN_LOWER_THAN_EXP;
 318                break;
 319        }
 320        mutex_unlock(&conn->sess->cmdsn_mutex);
 321
 322        if (reject)
 323                iscsit_reject_cmd(cmd, reason, buf);
 324
 325        return ret;
 326}
 327EXPORT_SYMBOL(iscsit_sequence_cmd);
 328
 329int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 330{
 331        struct iscsi_conn *conn = cmd->conn;
 332        struct se_cmd *se_cmd = &cmd->se_cmd;
 333        struct iscsi_data *hdr = (struct iscsi_data *) buf;
 334        u32 payload_length = ntoh24(hdr->dlength);
 335
 336        if (conn->sess->sess_ops->InitialR2T) {
 337                pr_err("Received unexpected unsolicited data"
 338                        " while InitialR2T=Yes, protocol error.\n");
 339                transport_send_check_condition_and_sense(se_cmd,
 340                                TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 341                return -1;
 342        }
 343
 344        if ((cmd->first_burst_len + payload_length) >
 345             conn->sess->sess_ops->FirstBurstLength) {
 346                pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 347                        " for this Unsolicited DataOut Burst.\n",
 348                        (cmd->first_burst_len + payload_length),
 349                                conn->sess->sess_ops->FirstBurstLength);
 350                transport_send_check_condition_and_sense(se_cmd,
 351                                TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 352                return -1;
 353        }
 354
 355        if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 356                return 0;
 357
 358        if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 359            ((cmd->first_burst_len + payload_length) !=
 360              conn->sess->sess_ops->FirstBurstLength)) {
 361                pr_err("Unsolicited non-immediate data received %u"
 362                        " does not equal FirstBurstLength: %u, and does"
 363                        " not equal ExpXferLen %u.\n",
 364                        (cmd->first_burst_len + payload_length),
 365                        conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 366                transport_send_check_condition_and_sense(se_cmd,
 367                                TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 368                return -1;
 369        }
 370        return 0;
 371}
 372
 373struct iscsi_cmd *iscsit_find_cmd_from_itt(
 374        struct iscsi_conn *conn,
 375        itt_t init_task_tag)
 376{
 377        struct iscsi_cmd *cmd;
 378
 379        spin_lock_bh(&conn->cmd_lock);
 380        list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 381                if (cmd->init_task_tag == init_task_tag) {
 382                        spin_unlock_bh(&conn->cmd_lock);
 383                        return cmd;
 384                }
 385        }
 386        spin_unlock_bh(&conn->cmd_lock);
 387
 388        pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 389                        init_task_tag, conn->cid);
 390        return NULL;
 391}
 392EXPORT_SYMBOL(iscsit_find_cmd_from_itt);
 393
 394struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 395        struct iscsi_conn *conn,
 396        itt_t init_task_tag,
 397        u32 length)
 398{
 399        struct iscsi_cmd *cmd;
 400
 401        spin_lock_bh(&conn->cmd_lock);
 402        list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 403                if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT)
 404                        continue;
 405                if (cmd->init_task_tag == init_task_tag) {
 406                        spin_unlock_bh(&conn->cmd_lock);
 407                        return cmd;
 408                }
 409        }
 410        spin_unlock_bh(&conn->cmd_lock);
 411
 412        pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 413                        " dumping payload\n", init_task_tag, conn->cid);
 414        if (length)
 415                iscsit_dump_data_payload(conn, length, 1);
 416
 417        return NULL;
 418}
 419
 420struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 421        struct iscsi_conn *conn,
 422        u32 targ_xfer_tag)
 423{
 424        struct iscsi_cmd *cmd = NULL;
 425
 426        spin_lock_bh(&conn->cmd_lock);
 427        list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 428                if (cmd->targ_xfer_tag == targ_xfer_tag) {
 429                        spin_unlock_bh(&conn->cmd_lock);
 430                        return cmd;
 431                }
 432        }
 433        spin_unlock_bh(&conn->cmd_lock);
 434
 435        pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 436                        targ_xfer_tag, conn->cid);
 437        return NULL;
 438}
 439
 440int iscsit_find_cmd_for_recovery(
 441        struct iscsi_session *sess,
 442        struct iscsi_cmd **cmd_ptr,
 443        struct iscsi_conn_recovery **cr_ptr,
 444        itt_t init_task_tag)
 445{
 446        struct iscsi_cmd *cmd = NULL;
 447        struct iscsi_conn_recovery *cr;
 448        /*
 449         * Scan through the inactive connection recovery list's command list.
 450         * If init_task_tag matches the command is still alligent.
 451         */
 452        spin_lock(&sess->cr_i_lock);
 453        list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 454                spin_lock(&cr->conn_recovery_cmd_lock);
 455                list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 456                        if (cmd->init_task_tag == init_task_tag) {
 457                                spin_unlock(&cr->conn_recovery_cmd_lock);
 458                                spin_unlock(&sess->cr_i_lock);
 459
 460                                *cr_ptr = cr;
 461                                *cmd_ptr = cmd;
 462                                return -2;
 463                        }
 464                }
 465                spin_unlock(&cr->conn_recovery_cmd_lock);
 466        }
 467        spin_unlock(&sess->cr_i_lock);
 468        /*
 469         * Scan through the active connection recovery list's command list.
 470         * If init_task_tag matches the command is ready to be reassigned.
 471         */
 472        spin_lock(&sess->cr_a_lock);
 473        list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 474                spin_lock(&cr->conn_recovery_cmd_lock);
 475                list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 476                        if (cmd->init_task_tag == init_task_tag) {
 477                                spin_unlock(&cr->conn_recovery_cmd_lock);
 478                                spin_unlock(&sess->cr_a_lock);
 479
 480                                *cr_ptr = cr;
 481                                *cmd_ptr = cmd;
 482                                return 0;
 483                        }
 484                }
 485                spin_unlock(&cr->conn_recovery_cmd_lock);
 486        }
 487        spin_unlock(&sess->cr_a_lock);
 488
 489        return -1;
 490}
 491
 492void iscsit_add_cmd_to_immediate_queue(
 493        struct iscsi_cmd *cmd,
 494        struct iscsi_conn *conn,
 495        u8 state)
 496{
 497        struct iscsi_queue_req *qr;
 498
 499        qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 500        if (!qr) {
 501                pr_err("Unable to allocate memory for"
 502                                " struct iscsi_queue_req\n");
 503                return;
 504        }
 505        INIT_LIST_HEAD(&qr->qr_list);
 506        qr->cmd = cmd;
 507        qr->state = state;
 508
 509        spin_lock_bh(&conn->immed_queue_lock);
 510        list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 511        atomic_inc(&cmd->immed_queue_count);
 512        atomic_set(&conn->check_immediate_queue, 1);
 513        spin_unlock_bh(&conn->immed_queue_lock);
 514
 515        wake_up(&conn->queues_wq);
 516}
 517
 518struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 519{
 520        struct iscsi_queue_req *qr;
 521
 522        spin_lock_bh(&conn->immed_queue_lock);
 523        if (list_empty(&conn->immed_queue_list)) {
 524                spin_unlock_bh(&conn->immed_queue_lock);
 525                return NULL;
 526        }
 527        qr = list_first_entry(&conn->immed_queue_list,
 528                              struct iscsi_queue_req, qr_list);
 529
 530        list_del(&qr->qr_list);
 531        if (qr->cmd)
 532                atomic_dec(&qr->cmd->immed_queue_count);
 533        spin_unlock_bh(&conn->immed_queue_lock);
 534
 535        return qr;
 536}
 537
 538static void iscsit_remove_cmd_from_immediate_queue(
 539        struct iscsi_cmd *cmd,
 540        struct iscsi_conn *conn)
 541{
 542        struct iscsi_queue_req *qr, *qr_tmp;
 543
 544        spin_lock_bh(&conn->immed_queue_lock);
 545        if (!atomic_read(&cmd->immed_queue_count)) {
 546                spin_unlock_bh(&conn->immed_queue_lock);
 547                return;
 548        }
 549
 550        list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 551                if (qr->cmd != cmd)
 552                        continue;
 553
 554                atomic_dec(&qr->cmd->immed_queue_count);
 555                list_del(&qr->qr_list);
 556                kmem_cache_free(lio_qr_cache, qr);
 557        }
 558        spin_unlock_bh(&conn->immed_queue_lock);
 559
 560        if (atomic_read(&cmd->immed_queue_count)) {
 561                pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 562                        cmd->init_task_tag,
 563                        atomic_read(&cmd->immed_queue_count));
 564        }
 565}
 566
 567void iscsit_add_cmd_to_response_queue(
 568        struct iscsi_cmd *cmd,
 569        struct iscsi_conn *conn,
 570        u8 state)
 571{
 572        struct iscsi_queue_req *qr;
 573
 574        qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 575        if (!qr) {
 576                pr_err("Unable to allocate memory for"
 577                        " struct iscsi_queue_req\n");
 578                return;
 579        }
 580        INIT_LIST_HEAD(&qr->qr_list);
 581        qr->cmd = cmd;
 582        qr->state = state;
 583
 584        spin_lock_bh(&conn->response_queue_lock);
 585        list_add_tail(&qr->qr_list, &conn->response_queue_list);
 586        atomic_inc(&cmd->response_queue_count);
 587        spin_unlock_bh(&conn->response_queue_lock);
 588
 589        wake_up(&conn->queues_wq);
 590}
 591
 592struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 593{
 594        struct iscsi_queue_req *qr;
 595
 596        spin_lock_bh(&conn->response_queue_lock);
 597        if (list_empty(&conn->response_queue_list)) {
 598                spin_unlock_bh(&conn->response_queue_lock);
 599                return NULL;
 600        }
 601
 602        qr = list_first_entry(&conn->response_queue_list,
 603                              struct iscsi_queue_req, qr_list);
 604
 605        list_del(&qr->qr_list);
 606        if (qr->cmd)
 607                atomic_dec(&qr->cmd->response_queue_count);
 608        spin_unlock_bh(&conn->response_queue_lock);
 609
 610        return qr;
 611}
 612
 613static void iscsit_remove_cmd_from_response_queue(
 614        struct iscsi_cmd *cmd,
 615        struct iscsi_conn *conn)
 616{
 617        struct iscsi_queue_req *qr, *qr_tmp;
 618
 619        spin_lock_bh(&conn->response_queue_lock);
 620        if (!atomic_read(&cmd->response_queue_count)) {
 621                spin_unlock_bh(&conn->response_queue_lock);
 622                return;
 623        }
 624
 625        list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 626                                qr_list) {
 627                if (qr->cmd != cmd)
 628                        continue;
 629
 630                atomic_dec(&qr->cmd->response_queue_count);
 631                list_del(&qr->qr_list);
 632                kmem_cache_free(lio_qr_cache, qr);
 633        }
 634        spin_unlock_bh(&conn->response_queue_lock);
 635
 636        if (atomic_read(&cmd->response_queue_count)) {
 637                pr_err("ITT: 0x%08x response_queue_count: %d\n",
 638                        cmd->init_task_tag,
 639                        atomic_read(&cmd->response_queue_count));
 640        }
 641}
 642
 643bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 644{
 645        bool empty;
 646
 647        spin_lock_bh(&conn->immed_queue_lock);
 648        empty = list_empty(&conn->immed_queue_list);
 649        spin_unlock_bh(&conn->immed_queue_lock);
 650
 651        if (!empty)
 652                return empty;
 653
 654        spin_lock_bh(&conn->response_queue_lock);
 655        empty = list_empty(&conn->response_queue_list);
 656        spin_unlock_bh(&conn->response_queue_lock);
 657
 658        return empty;
 659}
 660
 661void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 662{
 663        struct iscsi_queue_req *qr, *qr_tmp;
 664
 665        spin_lock_bh(&conn->immed_queue_lock);
 666        list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 667                list_del(&qr->qr_list);
 668                if (qr->cmd)
 669                        atomic_dec(&qr->cmd->immed_queue_count);
 670
 671                kmem_cache_free(lio_qr_cache, qr);
 672        }
 673        spin_unlock_bh(&conn->immed_queue_lock);
 674
 675        spin_lock_bh(&conn->response_queue_lock);
 676        list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 677                        qr_list) {
 678                list_del(&qr->qr_list);
 679                if (qr->cmd)
 680                        atomic_dec(&qr->cmd->response_queue_count);
 681
 682                kmem_cache_free(lio_qr_cache, qr);
 683        }
 684        spin_unlock_bh(&conn->response_queue_lock);
 685}
 686
 687void iscsit_release_cmd(struct iscsi_cmd *cmd)
 688{
 689        struct iscsi_session *sess;
 690        struct se_cmd *se_cmd = &cmd->se_cmd;
 691
 692        if (cmd->conn)
 693                sess = cmd->conn->sess;
 694        else
 695                sess = cmd->sess;
 696
 697        BUG_ON(!sess || !sess->se_sess);
 698
 699        kfree(cmd->buf_ptr);
 700        kfree(cmd->pdu_list);
 701        kfree(cmd->seq_list);
 702        kfree(cmd->tmr_req);
 703        kfree(cmd->iov_data);
 704        kfree(cmd->text_in_ptr);
 705
 706        percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 707}
 708EXPORT_SYMBOL(iscsit_release_cmd);
 709
 710void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool scsi_cmd,
 711                       bool check_queues)
 712{
 713        struct iscsi_conn *conn = cmd->conn;
 714
 715        if (scsi_cmd) {
 716                if (cmd->data_direction == DMA_TO_DEVICE) {
 717                        iscsit_stop_dataout_timer(cmd);
 718                        iscsit_free_r2ts_from_list(cmd);
 719                }
 720                if (cmd->data_direction == DMA_FROM_DEVICE)
 721                        iscsit_free_all_datain_reqs(cmd);
 722        }
 723
 724        if (conn && check_queues) {
 725                iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 726                iscsit_remove_cmd_from_response_queue(cmd, conn);
 727        }
 728}
 729
 730void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 731{
 732        struct se_cmd *se_cmd = NULL;
 733        int rc;
 734        /*
 735         * Determine if a struct se_cmd is associated with
 736         * this struct iscsi_cmd.
 737         */
 738        switch (cmd->iscsi_opcode) {
 739        case ISCSI_OP_SCSI_CMD:
 740                se_cmd = &cmd->se_cmd;
 741                __iscsit_free_cmd(cmd, true, shutdown);
 742                /*
 743                 * Fallthrough
 744                 */
 745        case ISCSI_OP_SCSI_TMFUNC:
 746                rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 747                if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
 748                        __iscsit_free_cmd(cmd, true, shutdown);
 749                        target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 750                }
 751                break;
 752        case ISCSI_OP_REJECT:
 753                /*
 754                 * Handle special case for REJECT when iscsi_add_reject*() has
 755                 * overwritten the original iscsi_opcode assignment, and the
 756                 * associated cmd->se_cmd needs to be released.
 757                 */
 758                if (cmd->se_cmd.se_tfo != NULL) {
 759                        se_cmd = &cmd->se_cmd;
 760                        __iscsit_free_cmd(cmd, true, shutdown);
 761
 762                        rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 763                        if (!rc && shutdown && se_cmd->se_sess) {
 764                                __iscsit_free_cmd(cmd, true, shutdown);
 765                                target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 766                        }
 767                        break;
 768                }
 769                /* Fall-through */
 770        default:
 771                __iscsit_free_cmd(cmd, false, shutdown);
 772                iscsit_release_cmd(cmd);
 773                break;
 774        }
 775}
 776
 777int iscsit_check_session_usage_count(struct iscsi_session *sess)
 778{
 779        spin_lock_bh(&sess->session_usage_lock);
 780        if (sess->session_usage_count != 0) {
 781                sess->session_waiting_on_uc = 1;
 782                spin_unlock_bh(&sess->session_usage_lock);
 783                if (in_interrupt())
 784                        return 2;
 785
 786                wait_for_completion(&sess->session_waiting_on_uc_comp);
 787                return 1;
 788        }
 789        spin_unlock_bh(&sess->session_usage_lock);
 790
 791        return 0;
 792}
 793
 794void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 795{
 796        spin_lock_bh(&sess->session_usage_lock);
 797        sess->session_usage_count--;
 798
 799        if (!sess->session_usage_count && sess->session_waiting_on_uc)
 800                complete(&sess->session_waiting_on_uc_comp);
 801
 802        spin_unlock_bh(&sess->session_usage_lock);
 803}
 804
 805void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 806{
 807        spin_lock_bh(&sess->session_usage_lock);
 808        sess->session_usage_count++;
 809        spin_unlock_bh(&sess->session_usage_lock);
 810}
 811
 812/*
 813 *      Setup conn->if_marker and conn->of_marker values based upon
 814 *      the initial marker-less interval. (see iSCSI v19 A.2)
 815 */
 816int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 817{
 818        int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 819        /*
 820         * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 821         */
 822        u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 823        u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 824
 825        if (conn->conn_ops->OFMarker) {
 826                /*
 827                 * Account for the first Login Command received not
 828                 * via iscsi_recv_msg().
 829                 */
 830                conn->of_marker += ISCSI_HDR_LEN;
 831                if (conn->of_marker <= OFMarkInt) {
 832                        conn->of_marker = (OFMarkInt - conn->of_marker);
 833                } else {
 834                        login_ofmarker_count = (conn->of_marker / OFMarkInt);
 835                        next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 836                                        (login_ofmarker_count * MARKER_SIZE);
 837                        conn->of_marker = (next_marker - conn->of_marker);
 838                }
 839                conn->of_marker_offset = 0;
 840                pr_debug("Setting OFMarker value to %u based on Initial"
 841                        " Markerless Interval.\n", conn->of_marker);
 842        }
 843
 844        if (conn->conn_ops->IFMarker) {
 845                if (conn->if_marker <= IFMarkInt) {
 846                        conn->if_marker = (IFMarkInt - conn->if_marker);
 847                } else {
 848                        login_ifmarker_count = (conn->if_marker / IFMarkInt);
 849                        next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 850                                        (login_ifmarker_count * MARKER_SIZE);
 851                        conn->if_marker = (next_marker - conn->if_marker);
 852                }
 853                pr_debug("Setting IFMarker value to %u based on Initial"
 854                        " Markerless Interval.\n", conn->if_marker);
 855        }
 856
 857        return 0;
 858}
 859
 860struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 861{
 862        struct iscsi_conn *conn;
 863
 864        spin_lock_bh(&sess->conn_lock);
 865        list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 866                if ((conn->cid == cid) &&
 867                    (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 868                        iscsit_inc_conn_usage_count(conn);
 869                        spin_unlock_bh(&sess->conn_lock);
 870                        return conn;
 871                }
 872        }
 873        spin_unlock_bh(&sess->conn_lock);
 874
 875        return NULL;
 876}
 877
 878struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 879{
 880        struct iscsi_conn *conn;
 881
 882        spin_lock_bh(&sess->conn_lock);
 883        list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 884                if (conn->cid == cid) {
 885                        iscsit_inc_conn_usage_count(conn);
 886                        spin_lock(&conn->state_lock);
 887                        atomic_set(&conn->connection_wait_rcfr, 1);
 888                        spin_unlock(&conn->state_lock);
 889                        spin_unlock_bh(&sess->conn_lock);
 890                        return conn;
 891                }
 892        }
 893        spin_unlock_bh(&sess->conn_lock);
 894
 895        return NULL;
 896}
 897
 898void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 899{
 900        spin_lock_bh(&conn->conn_usage_lock);
 901        if (conn->conn_usage_count != 0) {
 902                conn->conn_waiting_on_uc = 1;
 903                spin_unlock_bh(&conn->conn_usage_lock);
 904
 905                wait_for_completion(&conn->conn_waiting_on_uc_comp);
 906                return;
 907        }
 908        spin_unlock_bh(&conn->conn_usage_lock);
 909}
 910
 911void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 912{
 913        spin_lock_bh(&conn->conn_usage_lock);
 914        conn->conn_usage_count--;
 915
 916        if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 917                complete(&conn->conn_waiting_on_uc_comp);
 918
 919        spin_unlock_bh(&conn->conn_usage_lock);
 920}
 921
 922void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 923{
 924        spin_lock_bh(&conn->conn_usage_lock);
 925        conn->conn_usage_count++;
 926        spin_unlock_bh(&conn->conn_usage_lock);
 927}
 928
 929static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 930{
 931        u8 state;
 932        struct iscsi_cmd *cmd;
 933
 934        cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
 935        if (!cmd)
 936                return -1;
 937
 938        cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 939        state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 940                                ISTATE_SEND_NOPIN_NO_RESPONSE;
 941        cmd->init_task_tag = RESERVED_ITT;
 942        cmd->targ_xfer_tag = (want_response) ?
 943                             session_get_next_ttt(conn->sess) : 0xFFFFFFFF;
 944        spin_lock_bh(&conn->cmd_lock);
 945        list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 946        spin_unlock_bh(&conn->cmd_lock);
 947
 948        if (want_response)
 949                iscsit_start_nopin_response_timer(conn);
 950        iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 951
 952        return 0;
 953}
 954
 955static void iscsit_handle_nopin_response_timeout(unsigned long data)
 956{
 957        struct iscsi_conn *conn = (struct iscsi_conn *) data;
 958
 959        iscsit_inc_conn_usage_count(conn);
 960
 961        spin_lock_bh(&conn->nopin_timer_lock);
 962        if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 963                spin_unlock_bh(&conn->nopin_timer_lock);
 964                iscsit_dec_conn_usage_count(conn);
 965                return;
 966        }
 967
 968        pr_debug("Did not receive response to NOPIN on CID: %hu on"
 969                " SID: %u, failing connection.\n", conn->cid,
 970                        conn->sess->sid);
 971        conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 972        spin_unlock_bh(&conn->nopin_timer_lock);
 973
 974        {
 975        struct iscsi_portal_group *tpg = conn->sess->tpg;
 976        struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 977
 978        if (tiqn) {
 979                spin_lock_bh(&tiqn->sess_err_stats.lock);
 980                strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 981                                conn->sess->sess_ops->InitiatorName);
 982                tiqn->sess_err_stats.last_sess_failure_type =
 983                                ISCSI_SESS_ERR_CXN_TIMEOUT;
 984                tiqn->sess_err_stats.cxn_timeout_errors++;
 985                atomic_long_inc(&conn->sess->conn_timeout_errors);
 986                spin_unlock_bh(&tiqn->sess_err_stats.lock);
 987        }
 988        }
 989
 990        iscsit_cause_connection_reinstatement(conn, 0);
 991        iscsit_dec_conn_usage_count(conn);
 992}
 993
 994void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 995{
 996        struct iscsi_session *sess = conn->sess;
 997        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 998
 999        spin_lock_bh(&conn->nopin_timer_lock);
1000        if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1001                spin_unlock_bh(&conn->nopin_timer_lock);
1002                return;
1003        }
1004
1005        mod_timer(&conn->nopin_response_timer,
1006                (get_jiffies_64() + na->nopin_response_timeout * HZ));
1007        spin_unlock_bh(&conn->nopin_timer_lock);
1008}
1009
1010/*
1011 *      Called with conn->nopin_timer_lock held.
1012 */
1013void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
1014{
1015        struct iscsi_session *sess = conn->sess;
1016        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1017
1018        spin_lock_bh(&conn->nopin_timer_lock);
1019        if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
1020                spin_unlock_bh(&conn->nopin_timer_lock);
1021                return;
1022        }
1023
1024        init_timer(&conn->nopin_response_timer);
1025        conn->nopin_response_timer.expires =
1026                (get_jiffies_64() + na->nopin_response_timeout * HZ);
1027        conn->nopin_response_timer.data = (unsigned long)conn;
1028        conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
1029        conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
1030        conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
1031        add_timer(&conn->nopin_response_timer);
1032
1033        pr_debug("Started NOPIN Response Timer on CID: %d to %u"
1034                " seconds\n", conn->cid, na->nopin_response_timeout);
1035        spin_unlock_bh(&conn->nopin_timer_lock);
1036}
1037
1038void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
1039{
1040        spin_lock_bh(&conn->nopin_timer_lock);
1041        if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1042                spin_unlock_bh(&conn->nopin_timer_lock);
1043                return;
1044        }
1045        conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1046        spin_unlock_bh(&conn->nopin_timer_lock);
1047
1048        del_timer_sync(&conn->nopin_response_timer);
1049
1050        spin_lock_bh(&conn->nopin_timer_lock);
1051        conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1052        spin_unlock_bh(&conn->nopin_timer_lock);
1053}
1054
1055static void iscsit_handle_nopin_timeout(unsigned long data)
1056{
1057        struct iscsi_conn *conn = (struct iscsi_conn *) data;
1058
1059        iscsit_inc_conn_usage_count(conn);
1060
1061        spin_lock_bh(&conn->nopin_timer_lock);
1062        if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1063                spin_unlock_bh(&conn->nopin_timer_lock);
1064                iscsit_dec_conn_usage_count(conn);
1065                return;
1066        }
1067        conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1068        spin_unlock_bh(&conn->nopin_timer_lock);
1069
1070        iscsit_add_nopin(conn, 1);
1071        iscsit_dec_conn_usage_count(conn);
1072}
1073
1074/*
1075 * Called with conn->nopin_timer_lock held.
1076 */
1077void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1078{
1079        struct iscsi_session *sess = conn->sess;
1080        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1081        /*
1082        * NOPIN timeout is disabled.
1083         */
1084        if (!na->nopin_timeout)
1085                return;
1086
1087        if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1088                return;
1089
1090        init_timer(&conn->nopin_timer);
1091        conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1092        conn->nopin_timer.data = (unsigned long)conn;
1093        conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1094        conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1095        conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1096        add_timer(&conn->nopin_timer);
1097
1098        pr_debug("Started NOPIN Timer on CID: %d at %u second"
1099                " interval\n", conn->cid, na->nopin_timeout);
1100}
1101
1102void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1103{
1104        struct iscsi_session *sess = conn->sess;
1105        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1106        /*
1107         * NOPIN timeout is disabled..
1108         */
1109        if (!na->nopin_timeout)
1110                return;
1111
1112        spin_lock_bh(&conn->nopin_timer_lock);
1113        if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1114                spin_unlock_bh(&conn->nopin_timer_lock);
1115                return;
1116        }
1117
1118        init_timer(&conn->nopin_timer);
1119        conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1120        conn->nopin_timer.data = (unsigned long)conn;
1121        conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1122        conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1123        conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1124        add_timer(&conn->nopin_timer);
1125
1126        pr_debug("Started NOPIN Timer on CID: %d at %u second"
1127                        " interval\n", conn->cid, na->nopin_timeout);
1128        spin_unlock_bh(&conn->nopin_timer_lock);
1129}
1130
1131void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1132{
1133        spin_lock_bh(&conn->nopin_timer_lock);
1134        if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1135                spin_unlock_bh(&conn->nopin_timer_lock);
1136                return;
1137        }
1138        conn->nopin_timer_flags |= ISCSI_TF_STOP;
1139        spin_unlock_bh(&conn->nopin_timer_lock);
1140
1141        del_timer_sync(&conn->nopin_timer);
1142
1143        spin_lock_bh(&conn->nopin_timer_lock);
1144        conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1145        spin_unlock_bh(&conn->nopin_timer_lock);
1146}
1147
1148int iscsit_send_tx_data(
1149        struct iscsi_cmd *cmd,
1150        struct iscsi_conn *conn,
1151        int use_misc)
1152{
1153        int tx_sent, tx_size;
1154        u32 iov_count;
1155        struct kvec *iov;
1156
1157send_data:
1158        tx_size = cmd->tx_size;
1159
1160        if (!use_misc) {
1161                iov = &cmd->iov_data[0];
1162                iov_count = cmd->iov_data_count;
1163        } else {
1164                iov = &cmd->iov_misc[0];
1165                iov_count = cmd->iov_misc_count;
1166        }
1167
1168        tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1169        if (tx_size != tx_sent) {
1170                if (tx_sent == -EAGAIN) {
1171                        pr_err("tx_data() returned -EAGAIN\n");
1172                        goto send_data;
1173                } else
1174                        return -1;
1175        }
1176        cmd->tx_size = 0;
1177
1178        return 0;
1179}
1180
1181int iscsit_fe_sendpage_sg(
1182        struct iscsi_cmd *cmd,
1183        struct iscsi_conn *conn)
1184{
1185        struct scatterlist *sg = cmd->first_data_sg;
1186        struct kvec iov;
1187        u32 tx_hdr_size, data_len;
1188        u32 offset = cmd->first_data_sg_off;
1189        int tx_sent, iov_off;
1190
1191send_hdr:
1192        tx_hdr_size = ISCSI_HDR_LEN;
1193        if (conn->conn_ops->HeaderDigest)
1194                tx_hdr_size += ISCSI_CRC_LEN;
1195
1196        iov.iov_base = cmd->pdu;
1197        iov.iov_len = tx_hdr_size;
1198
1199        tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1200        if (tx_hdr_size != tx_sent) {
1201                if (tx_sent == -EAGAIN) {
1202                        pr_err("tx_data() returned -EAGAIN\n");
1203                        goto send_hdr;
1204                }
1205                return -1;
1206        }
1207
1208        data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1209        /*
1210         * Set iov_off used by padding and data digest tx_data() calls below
1211         * in order to determine proper offset into cmd->iov_data[]
1212         */
1213        if (conn->conn_ops->DataDigest) {
1214                data_len -= ISCSI_CRC_LEN;
1215                if (cmd->padding)
1216                        iov_off = (cmd->iov_data_count - 2);
1217                else
1218                        iov_off = (cmd->iov_data_count - 1);
1219        } else {
1220                iov_off = (cmd->iov_data_count - 1);
1221        }
1222        /*
1223         * Perform sendpage() for each page in the scatterlist
1224         */
1225        while (data_len) {
1226                u32 space = (sg->length - offset);
1227                u32 sub_len = min_t(u32, data_len, space);
1228send_pg:
1229                tx_sent = conn->sock->ops->sendpage(conn->sock,
1230                                        sg_page(sg), sg->offset + offset, sub_len, 0);
1231                if (tx_sent != sub_len) {
1232                        if (tx_sent == -EAGAIN) {
1233                                pr_err("tcp_sendpage() returned"
1234                                                " -EAGAIN\n");
1235                                goto send_pg;
1236                        }
1237
1238                        pr_err("tcp_sendpage() failure: %d\n",
1239                                        tx_sent);
1240                        return -1;
1241                }
1242
1243                data_len -= sub_len;
1244                offset = 0;
1245                sg = sg_next(sg);
1246        }
1247
1248send_padding:
1249        if (cmd->padding) {
1250                struct kvec *iov_p = &cmd->iov_data[iov_off++];
1251
1252                tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1253                if (cmd->padding != tx_sent) {
1254                        if (tx_sent == -EAGAIN) {
1255                                pr_err("tx_data() returned -EAGAIN\n");
1256                                goto send_padding;
1257                        }
1258                        return -1;
1259                }
1260        }
1261
1262send_datacrc:
1263        if (conn->conn_ops->DataDigest) {
1264                struct kvec *iov_d = &cmd->iov_data[iov_off];
1265
1266                tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1267                if (ISCSI_CRC_LEN != tx_sent) {
1268                        if (tx_sent == -EAGAIN) {
1269                                pr_err("tx_data() returned -EAGAIN\n");
1270                                goto send_datacrc;
1271                        }
1272                        return -1;
1273                }
1274        }
1275
1276        return 0;
1277}
1278
1279/*
1280 *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1281 *      back to the Initiator when an expection condition occurs with the
1282 *      errors set in status_class and status_detail.
1283 *
1284 *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1285 *      Returns:        0 on success, -1 on error.
1286 */
1287int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1288{
1289        struct iscsi_login_rsp *hdr;
1290        struct iscsi_login *login = conn->conn_login;
1291
1292        login->login_failed = 1;
1293        iscsit_collect_login_stats(conn, status_class, status_detail);
1294
1295        memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1296
1297        hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1298        hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1299        hdr->status_class       = status_class;
1300        hdr->status_detail      = status_detail;
1301        hdr->itt                = conn->login_itt;
1302
1303        return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1304}
1305
1306void iscsit_print_session_params(struct iscsi_session *sess)
1307{
1308        struct iscsi_conn *conn;
1309
1310        pr_debug("-----------------------------[Session Params for"
1311                " SID: %u]-----------------------------\n", sess->sid);
1312        spin_lock_bh(&sess->conn_lock);
1313        list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1314                iscsi_dump_conn_ops(conn->conn_ops);
1315        spin_unlock_bh(&sess->conn_lock);
1316
1317        iscsi_dump_sess_ops(sess->sess_ops);
1318}
1319
1320static int iscsit_do_rx_data(
1321        struct iscsi_conn *conn,
1322        struct iscsi_data_count *count)
1323{
1324        int data = count->data_length, rx_loop = 0, total_rx = 0;
1325        struct msghdr msg;
1326
1327        if (!conn || !conn->sock || !conn->conn_ops)
1328                return -1;
1329
1330        memset(&msg, 0, sizeof(struct msghdr));
1331        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC,
1332                      count->iov, count->iov_count, data);
1333
1334        while (total_rx < data) {
1335                rx_loop = sock_recvmsg(conn->sock, &msg,
1336                                      (data - total_rx), MSG_WAITALL);
1337                if (rx_loop <= 0) {
1338                        pr_debug("rx_loop: %d total_rx: %d\n",
1339                                rx_loop, total_rx);
1340                        return rx_loop;
1341                }
1342                total_rx += rx_loop;
1343                pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1344                                rx_loop, total_rx, data);
1345        }
1346
1347        return total_rx;
1348}
1349
1350static int iscsit_do_tx_data(
1351        struct iscsi_conn *conn,
1352        struct iscsi_data_count *count)
1353{
1354        int ret, iov_len;
1355        struct kvec *iov_p;
1356        struct msghdr msg;
1357
1358        if (!conn || !conn->sock || !conn->conn_ops)
1359                return -1;
1360
1361        if (count->data_length <= 0) {
1362                pr_err("Data length is: %d\n", count->data_length);
1363                return -1;
1364        }
1365
1366        memset(&msg, 0, sizeof(struct msghdr));
1367
1368        iov_p = count->iov;
1369        iov_len = count->iov_count;
1370
1371        ret = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1372                             count->data_length);
1373        if (ret != count->data_length) {
1374                pr_err("Unexpected ret: %d send data %d\n",
1375                       ret, count->data_length);
1376                return -EPIPE;
1377        }
1378        pr_debug("ret: %d, sent data: %d\n", ret, count->data_length);
1379
1380        return ret;
1381}
1382
1383int rx_data(
1384        struct iscsi_conn *conn,
1385        struct kvec *iov,
1386        int iov_count,
1387        int data)
1388{
1389        struct iscsi_data_count c;
1390
1391        if (!conn || !conn->sock || !conn->conn_ops)
1392                return -1;
1393
1394        memset(&c, 0, sizeof(struct iscsi_data_count));
1395        c.iov = iov;
1396        c.iov_count = iov_count;
1397        c.data_length = data;
1398        c.type = ISCSI_RX_DATA;
1399
1400        return iscsit_do_rx_data(conn, &c);
1401}
1402
1403int tx_data(
1404        struct iscsi_conn *conn,
1405        struct kvec *iov,
1406        int iov_count,
1407        int data)
1408{
1409        struct iscsi_data_count c;
1410
1411        if (!conn || !conn->sock || !conn->conn_ops)
1412                return -1;
1413
1414        memset(&c, 0, sizeof(struct iscsi_data_count));
1415        c.iov = iov;
1416        c.iov_count = iov_count;
1417        c.data_length = data;
1418        c.type = ISCSI_TX_DATA;
1419
1420        return iscsit_do_tx_data(conn, &c);
1421}
1422
1423void iscsit_collect_login_stats(
1424        struct iscsi_conn *conn,
1425        u8 status_class,
1426        u8 status_detail)
1427{
1428        struct iscsi_param *intrname = NULL;
1429        struct iscsi_tiqn *tiqn;
1430        struct iscsi_login_stats *ls;
1431
1432        tiqn = iscsit_snmp_get_tiqn(conn);
1433        if (!tiqn)
1434                return;
1435
1436        ls = &tiqn->login_stats;
1437
1438        spin_lock(&ls->lock);
1439        if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1440            ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1441                /* We already have the failure info for this login */
1442                spin_unlock(&ls->lock);
1443                return;
1444        }
1445
1446        if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1447                ls->accepts++;
1448        else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1449                ls->redirects++;
1450                ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1451        } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1452                 (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1453                ls->authenticate_fails++;
1454                ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1455        } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1456                 (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1457                ls->authorize_fails++;
1458                ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1459        } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1460                 (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1461                ls->negotiate_fails++;
1462                ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1463        } else {
1464                ls->other_fails++;
1465                ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1466        }
1467
1468        /* Save initiator name, ip address and time, if it is a failed login */
1469        if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1470                if (conn->param_list)
1471                        intrname = iscsi_find_param_from_key(INITIATORNAME,
1472                                                             conn->param_list);
1473                strlcpy(ls->last_intr_fail_name,
1474                       (intrname ? intrname->value : "Unknown"),
1475                       sizeof(ls->last_intr_fail_name));
1476
1477                ls->last_intr_fail_ip_family = conn->login_family;
1478
1479                snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1480                                "%s", conn->login_ip);
1481                ls->last_fail_time = get_jiffies_64();
1482        }
1483
1484        spin_unlock(&ls->lock);
1485}
1486
1487struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1488{
1489        struct iscsi_portal_group *tpg;
1490
1491        if (!conn || !conn->sess)
1492                return NULL;
1493
1494        tpg = conn->sess->tpg;
1495        if (!tpg)
1496                return NULL;
1497
1498        if (!tpg->tpg_tiqn)
1499                return NULL;
1500
1501        return tpg->tpg_tiqn;
1502}
1503