linux/drivers/target/iscsi/iscsi_target_erl1.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*******************************************************************************
   3 * This file contains error recovery level one used by the iSCSI Target driver.
   4 *
   5 * (c) Copyright 2007-2013 Datera, Inc.
   6 *
   7 * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   8 *
   9 ******************************************************************************/
  10
  11#include <linux/list.h>
  12#include <linux/slab.h>
  13#include <scsi/iscsi_proto.h>
  14#include <target/target_core_base.h>
  15#include <target/target_core_fabric.h>
  16#include <target/iscsi/iscsi_transport.h>
  17
  18#include <target/iscsi/iscsi_target_core.h>
  19#include "iscsi_target_seq_pdu_list.h"
  20#include "iscsi_target_datain_values.h"
  21#include "iscsi_target_device.h"
  22#include "iscsi_target_tpg.h"
  23#include "iscsi_target_util.h"
  24#include "iscsi_target_erl0.h"
  25#include "iscsi_target_erl1.h"
  26#include "iscsi_target_erl2.h"
  27#include "iscsi_target.h"
  28
  29#define OFFLOAD_BUF_SIZE        32768U
  30
  31/*
  32 *      Used to dump excess datain payload for certain error recovery
  33 *      situations.  Receive in OFFLOAD_BUF_SIZE max of datain per rx_data().
  34 *
  35 *      dump_padding_digest denotes if padding and data digests need
  36 *      to be dumped.
  37 */
  38int iscsit_dump_data_payload(
  39        struct iscsit_conn *conn,
  40        u32 buf_len,
  41        int dump_padding_digest)
  42{
  43        char *buf;
  44        int ret = DATAOUT_WITHIN_COMMAND_RECOVERY, rx_got;
  45        u32 length, offset = 0, size;
  46        struct kvec iov;
  47
  48        if (conn->sess->sess_ops->RDMAExtensions)
  49                return 0;
  50
  51        if (dump_padding_digest) {
  52                buf_len = ALIGN(buf_len, 4);
  53                if (conn->conn_ops->DataDigest)
  54                        buf_len += ISCSI_CRC_LEN;
  55        }
  56
  57        length = min(buf_len, OFFLOAD_BUF_SIZE);
  58
  59        buf = kzalloc(length, GFP_ATOMIC);
  60        if (!buf) {
  61                pr_err("Unable to allocate %u bytes for offload"
  62                                " buffer.\n", length);
  63                return -1;
  64        }
  65        memset(&iov, 0, sizeof(struct kvec));
  66
  67        while (offset < buf_len) {
  68                size = min(buf_len - offset, length);
  69
  70                iov.iov_len = size;
  71                iov.iov_base = buf;
  72
  73                rx_got = rx_data(conn, &iov, 1, size);
  74                if (rx_got != size) {
  75                        ret = DATAOUT_CANNOT_RECOVER;
  76                        break;
  77                }
  78
  79                offset += size;
  80        }
  81
  82        kfree(buf);
  83        return ret;
  84}
  85
  86/*
  87 *      Used for retransmitting R2Ts from a R2T SNACK request.
  88 */
  89static int iscsit_send_recovery_r2t_for_snack(
  90        struct iscsit_cmd *cmd,
  91        struct iscsi_r2t *r2t)
  92{
  93        /*
  94         * If the struct iscsi_r2t has not been sent yet, we can safely
  95         * ignore retransmission
  96         * of the R2TSN in question.
  97         */
  98        spin_lock_bh(&cmd->r2t_lock);
  99        if (!r2t->sent_r2t) {
 100                spin_unlock_bh(&cmd->r2t_lock);
 101                return 0;
 102        }
 103        r2t->sent_r2t = 0;
 104        spin_unlock_bh(&cmd->r2t_lock);
 105
 106        iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
 107
 108        return 0;
 109}
 110
 111static int iscsit_handle_r2t_snack(
 112        struct iscsit_cmd *cmd,
 113        unsigned char *buf,
 114        u32 begrun,
 115        u32 runlength)
 116{
 117        u32 last_r2tsn;
 118        struct iscsi_r2t *r2t;
 119
 120        /*
 121         * Make sure the initiator is not requesting retransmission
 122         * of R2TSNs already acknowledged by a TMR TASK_REASSIGN.
 123         */
 124        if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
 125            (begrun <= cmd->acked_data_sn)) {
 126                pr_err("ITT: 0x%08x, R2T SNACK requesting"
 127                        " retransmission of R2TSN: 0x%08x to 0x%08x but already"
 128                        " acked to  R2TSN: 0x%08x by TMR TASK_REASSIGN,"
 129                        " protocol error.\n", cmd->init_task_tag, begrun,
 130                        (begrun + runlength), cmd->acked_data_sn);
 131
 132                return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
 133        }
 134
 135        if (runlength) {
 136                if ((begrun + runlength) > cmd->r2t_sn) {
 137                        pr_err("Command ITT: 0x%08x received R2T SNACK"
 138                        " with BegRun: 0x%08x, RunLength: 0x%08x, exceeds"
 139                        " current R2TSN: 0x%08x, protocol error.\n",
 140                        cmd->init_task_tag, begrun, runlength, cmd->r2t_sn);
 141                        return iscsit_reject_cmd(cmd,
 142                                        ISCSI_REASON_BOOKMARK_INVALID, buf);
 143                }
 144                last_r2tsn = (begrun + runlength);
 145        } else
 146                last_r2tsn = cmd->r2t_sn;
 147
 148        while (begrun < last_r2tsn) {
 149                r2t = iscsit_get_holder_for_r2tsn(cmd, begrun);
 150                if (!r2t)
 151                        return -1;
 152                if (iscsit_send_recovery_r2t_for_snack(cmd, r2t) < 0)
 153                        return -1;
 154
 155                begrun++;
 156        }
 157
 158        return 0;
 159}
 160
 161/*
 162 *      Generates Offsets and NextBurstLength based on Begrun and Runlength
 163 *      carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
 164 *
 165 *      For DataSequenceInOrder=Yes and DataPDUInOrder=[Yes,No] only.
 166 *
 167 *      FIXME: How is this handled for a RData SNACK?
 168 */
 169int iscsit_create_recovery_datain_values_datasequenceinorder_yes(
 170        struct iscsit_cmd *cmd,
 171        struct iscsi_datain_req *dr)
 172{
 173        u32 data_sn = 0, data_sn_count = 0;
 174        u32 pdu_start = 0, seq_no = 0;
 175        u32 begrun = dr->begrun;
 176        struct iscsit_conn *conn = cmd->conn;
 177
 178        while (begrun > data_sn++) {
 179                data_sn_count++;
 180                if ((dr->next_burst_len +
 181                     conn->conn_ops->MaxRecvDataSegmentLength) <
 182                     conn->sess->sess_ops->MaxBurstLength) {
 183                        dr->read_data_done +=
 184                                conn->conn_ops->MaxRecvDataSegmentLength;
 185                        dr->next_burst_len +=
 186                                conn->conn_ops->MaxRecvDataSegmentLength;
 187                } else {
 188                        dr->read_data_done +=
 189                                (conn->sess->sess_ops->MaxBurstLength -
 190                                 dr->next_burst_len);
 191                        dr->next_burst_len = 0;
 192                        pdu_start += data_sn_count;
 193                        data_sn_count = 0;
 194                        seq_no++;
 195                }
 196        }
 197
 198        if (!conn->sess->sess_ops->DataPDUInOrder) {
 199                cmd->seq_no = seq_no;
 200                cmd->pdu_start = pdu_start;
 201                cmd->pdu_send_order = data_sn_count;
 202        }
 203
 204        return 0;
 205}
 206
 207/*
 208 *      Generates Offsets and NextBurstLength based on Begrun and Runlength
 209 *      carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
 210 *
 211 *      For DataSequenceInOrder=No and DataPDUInOrder=[Yes,No] only.
 212 *
 213 *      FIXME: How is this handled for a RData SNACK?
 214 */
 215int iscsit_create_recovery_datain_values_datasequenceinorder_no(
 216        struct iscsit_cmd *cmd,
 217        struct iscsi_datain_req *dr)
 218{
 219        int found_seq = 0, i;
 220        u32 data_sn, read_data_done = 0, seq_send_order = 0;
 221        u32 begrun = dr->begrun;
 222        u32 runlength = dr->runlength;
 223        struct iscsit_conn *conn = cmd->conn;
 224        struct iscsi_seq *first_seq = NULL, *seq = NULL;
 225
 226        if (!cmd->seq_list) {
 227                pr_err("struct iscsit_cmd->seq_list is NULL!\n");
 228                return -1;
 229        }
 230
 231        /*
 232         * Calculate read_data_done for all sequences containing a
 233         * first_datasn and last_datasn less than the BegRun.
 234         *
 235         * Locate the struct iscsi_seq the BegRun lies within and calculate
 236         * NextBurstLenghth up to the DataSN based on MaxRecvDataSegmentLength.
 237         *
 238         * Also use struct iscsi_seq->seq_send_order to determine where to start.
 239         */
 240        for (i = 0; i < cmd->seq_count; i++) {
 241                seq = &cmd->seq_list[i];
 242
 243                if (!seq->seq_send_order)
 244                        first_seq = seq;
 245
 246                /*
 247                 * No data has been transferred for this DataIN sequence, so the
 248                 * seq->first_datasn and seq->last_datasn have not been set.
 249                 */
 250                if (!seq->sent) {
 251                        pr_err("Ignoring non-sent sequence 0x%08x ->"
 252                                " 0x%08x\n\n", seq->first_datasn,
 253                                seq->last_datasn);
 254                        continue;
 255                }
 256
 257                /*
 258                 * This DataIN sequence is precedes the received BegRun, add the
 259                 * total xfer_len of the sequence to read_data_done and reset
 260                 * seq->pdu_send_order.
 261                 */
 262                if ((seq->first_datasn < begrun) &&
 263                                (seq->last_datasn < begrun)) {
 264                        pr_err("Pre BegRun sequence 0x%08x ->"
 265                                " 0x%08x\n", seq->first_datasn,
 266                                seq->last_datasn);
 267
 268                        read_data_done += cmd->seq_list[i].xfer_len;
 269                        seq->next_burst_len = seq->pdu_send_order = 0;
 270                        continue;
 271                }
 272
 273                /*
 274                 * The BegRun lies within this DataIN sequence.
 275                 */
 276                if ((seq->first_datasn <= begrun) &&
 277                                (seq->last_datasn >= begrun)) {
 278                        pr_err("Found sequence begrun: 0x%08x in"
 279                                " 0x%08x -> 0x%08x\n", begrun,
 280                                seq->first_datasn, seq->last_datasn);
 281
 282                        seq_send_order = seq->seq_send_order;
 283                        data_sn = seq->first_datasn;
 284                        seq->next_burst_len = seq->pdu_send_order = 0;
 285                        found_seq = 1;
 286
 287                        /*
 288                         * For DataPDUInOrder=Yes, while the first DataSN of
 289                         * the sequence is less than the received BegRun, add
 290                         * the MaxRecvDataSegmentLength to read_data_done and
 291                         * to the sequence's next_burst_len;
 292                         *
 293                         * For DataPDUInOrder=No, while the first DataSN of the
 294                         * sequence is less than the received BegRun, find the
 295                         * struct iscsi_pdu of the DataSN in question and add the
 296                         * MaxRecvDataSegmentLength to read_data_done and to the
 297                         * sequence's next_burst_len;
 298                         */
 299                        if (conn->sess->sess_ops->DataPDUInOrder) {
 300                                while (data_sn < begrun) {
 301                                        seq->pdu_send_order++;
 302                                        read_data_done +=
 303                                                conn->conn_ops->MaxRecvDataSegmentLength;
 304                                        seq->next_burst_len +=
 305                                                conn->conn_ops->MaxRecvDataSegmentLength;
 306                                        data_sn++;
 307                                }
 308                        } else {
 309                                int j;
 310                                struct iscsi_pdu *pdu;
 311
 312                                while (data_sn < begrun) {
 313                                        seq->pdu_send_order++;
 314
 315                                        for (j = 0; j < seq->pdu_count; j++) {
 316                                                pdu = &cmd->pdu_list[
 317                                                        seq->pdu_start + j];
 318                                                if (pdu->data_sn == data_sn) {
 319                                                        read_data_done +=
 320                                                                pdu->length;
 321                                                        seq->next_burst_len +=
 322                                                                pdu->length;
 323                                                }
 324                                        }
 325                                        data_sn++;
 326                                }
 327                        }
 328                        continue;
 329                }
 330
 331                /*
 332                 * This DataIN sequence is larger than the received BegRun,
 333                 * reset seq->pdu_send_order and continue.
 334                 */
 335                if ((seq->first_datasn > begrun) ||
 336                                (seq->last_datasn > begrun)) {
 337                        pr_err("Post BegRun sequence 0x%08x -> 0x%08x\n",
 338                                        seq->first_datasn, seq->last_datasn);
 339
 340                        seq->next_burst_len = seq->pdu_send_order = 0;
 341                        continue;
 342                }
 343        }
 344
 345        if (!found_seq) {
 346                if (!begrun) {
 347                        if (!first_seq) {
 348                                pr_err("ITT: 0x%08x, Begrun: 0x%08x"
 349                                        " but first_seq is NULL\n",
 350                                        cmd->init_task_tag, begrun);
 351                                return -1;
 352                        }
 353                        seq_send_order = first_seq->seq_send_order;
 354                        seq->next_burst_len = seq->pdu_send_order = 0;
 355                        goto done;
 356                }
 357
 358                pr_err("Unable to locate struct iscsi_seq for ITT: 0x%08x,"
 359                        " BegRun: 0x%08x, RunLength: 0x%08x while"
 360                        " DataSequenceInOrder=No and DataPDUInOrder=%s.\n",
 361                                cmd->init_task_tag, begrun, runlength,
 362                        (conn->sess->sess_ops->DataPDUInOrder) ? "Yes" : "No");
 363                return -1;
 364        }
 365
 366done:
 367        dr->read_data_done = read_data_done;
 368        dr->seq_send_order = seq_send_order;
 369
 370        return 0;
 371}
 372
 373static int iscsit_handle_recovery_datain(
 374        struct iscsit_cmd *cmd,
 375        unsigned char *buf,
 376        u32 begrun,
 377        u32 runlength)
 378{
 379        struct iscsit_conn *conn = cmd->conn;
 380        struct iscsi_datain_req *dr;
 381        struct se_cmd *se_cmd = &cmd->se_cmd;
 382
 383        if (!(se_cmd->transport_state & CMD_T_COMPLETE)) {
 384                pr_err("Ignoring ITT: 0x%08x Data SNACK\n",
 385                                cmd->init_task_tag);
 386                return 0;
 387        }
 388
 389        /*
 390         * Make sure the initiator is not requesting retransmission
 391         * of DataSNs already acknowledged by a Data ACK SNACK.
 392         */
 393        if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
 394            (begrun <= cmd->acked_data_sn)) {
 395                pr_err("ITT: 0x%08x, Data SNACK requesting"
 396                        " retransmission of DataSN: 0x%08x to 0x%08x but"
 397                        " already acked to DataSN: 0x%08x by Data ACK SNACK,"
 398                        " protocol error.\n", cmd->init_task_tag, begrun,
 399                        (begrun + runlength), cmd->acked_data_sn);
 400
 401                return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
 402        }
 403
 404        /*
 405         * Make sure BegRun and RunLength in the Data SNACK are sane.
 406         * Note: (cmd->data_sn - 1) will carry the maximum DataSN sent.
 407         */
 408        if ((begrun + runlength) > (cmd->data_sn - 1)) {
 409                pr_err("Initiator requesting BegRun: 0x%08x, RunLength"
 410                        ": 0x%08x greater than maximum DataSN: 0x%08x.\n",
 411                                begrun, runlength, (cmd->data_sn - 1));
 412                return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID,
 413                                         buf);
 414        }
 415
 416        dr = iscsit_allocate_datain_req();
 417        if (!dr)
 418                return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_NO_RESOURCES,
 419                                         buf);
 420
 421        dr->data_sn = dr->begrun = begrun;
 422        dr->runlength = runlength;
 423        dr->generate_recovery_values = 1;
 424        dr->recovery = DATAIN_WITHIN_COMMAND_RECOVERY;
 425
 426        iscsit_attach_datain_req(cmd, dr);
 427
 428        cmd->i_state = ISTATE_SEND_DATAIN;
 429        iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
 430
 431        return 0;
 432}
 433
 434int iscsit_handle_recovery_datain_or_r2t(
 435        struct iscsit_conn *conn,
 436        unsigned char *buf,
 437        itt_t init_task_tag,
 438        u32 targ_xfer_tag,
 439        u32 begrun,
 440        u32 runlength)
 441{
 442        struct iscsit_cmd *cmd;
 443
 444        cmd = iscsit_find_cmd_from_itt(conn, init_task_tag);
 445        if (!cmd)
 446                return 0;
 447
 448        /*
 449         * FIXME: This will not work for bidi commands.
 450         */
 451        switch (cmd->data_direction) {
 452        case DMA_TO_DEVICE:
 453                return iscsit_handle_r2t_snack(cmd, buf, begrun, runlength);
 454        case DMA_FROM_DEVICE:
 455                return iscsit_handle_recovery_datain(cmd, buf, begrun,
 456                                runlength);
 457        default:
 458                pr_err("Unknown cmd->data_direction: 0x%02x\n",
 459                                cmd->data_direction);
 460                return -1;
 461        }
 462
 463        return 0;
 464}
 465
 466/* #warning FIXME: Status SNACK needs to be dependent on OPCODE!!! */
 467int iscsit_handle_status_snack(
 468        struct iscsit_conn *conn,
 469        itt_t init_task_tag,
 470        u32 targ_xfer_tag,
 471        u32 begrun,
 472        u32 runlength)
 473{
 474        struct iscsit_cmd *cmd = NULL;
 475        u32 last_statsn;
 476        int found_cmd;
 477
 478        if (!begrun) {
 479                begrun = conn->exp_statsn;
 480        } else if (conn->exp_statsn > begrun) {
 481                pr_err("Got Status SNACK Begrun: 0x%08x, RunLength:"
 482                        " 0x%08x but already got ExpStatSN: 0x%08x on CID:"
 483                        " %hu.\n", begrun, runlength, conn->exp_statsn,
 484                        conn->cid);
 485                return 0;
 486        }
 487
 488        last_statsn = (!runlength) ? conn->stat_sn : (begrun + runlength);
 489
 490        while (begrun < last_statsn) {
 491                found_cmd = 0;
 492
 493                spin_lock_bh(&conn->cmd_lock);
 494                list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 495                        if (cmd->stat_sn == begrun) {
 496                                found_cmd = 1;
 497                                break;
 498                        }
 499                }
 500                spin_unlock_bh(&conn->cmd_lock);
 501
 502                if (!found_cmd) {
 503                        pr_err("Unable to find StatSN: 0x%08x for"
 504                                " a Status SNACK, assuming this was a"
 505                                " protactic SNACK for an untransmitted"
 506                                " StatSN, ignoring.\n", begrun);
 507                        begrun++;
 508                        continue;
 509                }
 510
 511                spin_lock_bh(&cmd->istate_lock);
 512                if (cmd->i_state == ISTATE_SEND_DATAIN) {
 513                        spin_unlock_bh(&cmd->istate_lock);
 514                        pr_err("Ignoring Status SNACK for BegRun:"
 515                                " 0x%08x, RunLength: 0x%08x, assuming this was"
 516                                " a protactic SNACK for an untransmitted"
 517                                " StatSN\n", begrun, runlength);
 518                        begrun++;
 519                        continue;
 520                }
 521                spin_unlock_bh(&cmd->istate_lock);
 522
 523                cmd->i_state = ISTATE_SEND_STATUS_RECOVERY;
 524                iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
 525                begrun++;
 526        }
 527
 528        return 0;
 529}
 530
 531int iscsit_handle_data_ack(
 532        struct iscsit_conn *conn,
 533        u32 targ_xfer_tag,
 534        u32 begrun,
 535        u32 runlength)
 536{
 537        struct iscsit_cmd *cmd = NULL;
 538
 539        cmd = iscsit_find_cmd_from_ttt(conn, targ_xfer_tag);
 540        if (!cmd) {
 541                pr_err("Data ACK SNACK for TTT: 0x%08x is"
 542                        " invalid.\n", targ_xfer_tag);
 543                return -1;
 544        }
 545
 546        if (begrun <= cmd->acked_data_sn) {
 547                pr_err("ITT: 0x%08x Data ACK SNACK BegRUN: 0x%08x is"
 548                        " less than the already acked DataSN: 0x%08x.\n",
 549                        cmd->init_task_tag, begrun, cmd->acked_data_sn);
 550                return -1;
 551        }
 552
 553        /*
 554         * For Data ACK SNACK, BegRun is the next expected DataSN.
 555         * (see iSCSI v19: 10.16.6)
 556         */
 557        cmd->cmd_flags |= ICF_GOT_DATACK_SNACK;
 558        cmd->acked_data_sn = (begrun - 1);
 559
 560        pr_debug("Received Data ACK SNACK for ITT: 0x%08x,"
 561                " updated acked DataSN to 0x%08x.\n",
 562                        cmd->init_task_tag, cmd->acked_data_sn);
 563
 564        return 0;
 565}
 566
 567static int iscsit_send_recovery_r2t(
 568        struct iscsit_cmd *cmd,
 569        u32 offset,
 570        u32 xfer_len)
 571{
 572        int ret;
 573
 574        spin_lock_bh(&cmd->r2t_lock);
 575        ret = iscsit_add_r2t_to_list(cmd, offset, xfer_len, 1, 0);
 576        spin_unlock_bh(&cmd->r2t_lock);
 577
 578        return ret;
 579}
 580
 581int iscsit_dataout_datapduinorder_no_fbit(
 582        struct iscsit_cmd *cmd,
 583        struct iscsi_pdu *pdu)
 584{
 585        int i, send_recovery_r2t = 0, recovery = 0;
 586        u32 length = 0, offset = 0, pdu_count = 0, xfer_len = 0;
 587        struct iscsit_conn *conn = cmd->conn;
 588        struct iscsi_pdu *first_pdu = NULL;
 589
 590        /*
 591         * Get an struct iscsi_pdu pointer to the first PDU, and total PDU count
 592         * of the DataOUT sequence.
 593         */
 594        if (conn->sess->sess_ops->DataSequenceInOrder) {
 595                for (i = 0; i < cmd->pdu_count; i++) {
 596                        if (cmd->pdu_list[i].seq_no == pdu->seq_no) {
 597                                if (!first_pdu)
 598                                        first_pdu = &cmd->pdu_list[i];
 599                                xfer_len += cmd->pdu_list[i].length;
 600                                pdu_count++;
 601                        } else if (pdu_count)
 602                                break;
 603                }
 604        } else {
 605                struct iscsi_seq *seq = cmd->seq_ptr;
 606
 607                first_pdu = &cmd->pdu_list[seq->pdu_start];
 608                pdu_count = seq->pdu_count;
 609        }
 610
 611        if (!first_pdu || !pdu_count)
 612                return DATAOUT_CANNOT_RECOVER;
 613
 614        /*
 615         * Loop through the ending DataOUT Sequence checking each struct iscsi_pdu.
 616         * The following ugly logic does batching of not received PDUs.
 617         */
 618        for (i = 0; i < pdu_count; i++) {
 619                if (first_pdu[i].status == ISCSI_PDU_RECEIVED_OK) {
 620                        if (!send_recovery_r2t)
 621                                continue;
 622
 623                        if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
 624                                return DATAOUT_CANNOT_RECOVER;
 625
 626                        send_recovery_r2t = length = offset = 0;
 627                        continue;
 628                }
 629                /*
 630                 * Set recovery = 1 for any missing, CRC failed, or timed
 631                 * out PDUs to let the DataOUT logic know that this sequence
 632                 * has not been completed yet.
 633                 *
 634                 * Also, only send a Recovery R2T for ISCSI_PDU_NOT_RECEIVED.
 635                 * We assume if the PDU either failed CRC or timed out
 636                 * that a Recovery R2T has already been sent.
 637                 */
 638                recovery = 1;
 639
 640                if (first_pdu[i].status != ISCSI_PDU_NOT_RECEIVED)
 641                        continue;
 642
 643                if (!offset)
 644                        offset = first_pdu[i].offset;
 645                length += first_pdu[i].length;
 646
 647                send_recovery_r2t = 1;
 648        }
 649
 650        if (send_recovery_r2t)
 651                if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
 652                        return DATAOUT_CANNOT_RECOVER;
 653
 654        return (!recovery) ? DATAOUT_NORMAL : DATAOUT_WITHIN_COMMAND_RECOVERY;
 655}
 656
 657static int iscsit_recalculate_dataout_values(
 658        struct iscsit_cmd *cmd,
 659        u32 pdu_offset,
 660        u32 pdu_length,
 661        u32 *r2t_offset,
 662        u32 *r2t_length)
 663{
 664        int i;
 665        struct iscsit_conn *conn = cmd->conn;
 666        struct iscsi_pdu *pdu = NULL;
 667
 668        if (conn->sess->sess_ops->DataSequenceInOrder) {
 669                cmd->data_sn = 0;
 670
 671                if (conn->sess->sess_ops->DataPDUInOrder) {
 672                        *r2t_offset = cmd->write_data_done;
 673                        *r2t_length = (cmd->seq_end_offset -
 674                                        cmd->write_data_done);
 675                        return 0;
 676                }
 677
 678                *r2t_offset = cmd->seq_start_offset;
 679                *r2t_length = (cmd->seq_end_offset - cmd->seq_start_offset);
 680
 681                for (i = 0; i < cmd->pdu_count; i++) {
 682                        pdu = &cmd->pdu_list[i];
 683
 684                        if (pdu->status != ISCSI_PDU_RECEIVED_OK)
 685                                continue;
 686
 687                        if ((pdu->offset >= cmd->seq_start_offset) &&
 688                           ((pdu->offset + pdu->length) <=
 689                             cmd->seq_end_offset)) {
 690                                if (!cmd->unsolicited_data)
 691                                        cmd->next_burst_len -= pdu->length;
 692                                else
 693                                        cmd->first_burst_len -= pdu->length;
 694
 695                                cmd->write_data_done -= pdu->length;
 696                                pdu->status = ISCSI_PDU_NOT_RECEIVED;
 697                        }
 698                }
 699        } else {
 700                struct iscsi_seq *seq = NULL;
 701
 702                seq = iscsit_get_seq_holder(cmd, pdu_offset, pdu_length);
 703                if (!seq)
 704                        return -1;
 705
 706                *r2t_offset = seq->orig_offset;
 707                *r2t_length = seq->xfer_len;
 708
 709                cmd->write_data_done -= (seq->offset - seq->orig_offset);
 710                if (cmd->immediate_data)
 711                        cmd->first_burst_len = cmd->write_data_done;
 712
 713                seq->data_sn = 0;
 714                seq->offset = seq->orig_offset;
 715                seq->next_burst_len = 0;
 716                seq->status = DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY;
 717
 718                if (conn->sess->sess_ops->DataPDUInOrder)
 719                        return 0;
 720
 721                for (i = 0; i < seq->pdu_count; i++) {
 722                        pdu = &cmd->pdu_list[i+seq->pdu_start];
 723
 724                        if (pdu->status != ISCSI_PDU_RECEIVED_OK)
 725                                continue;
 726
 727                        pdu->status = ISCSI_PDU_NOT_RECEIVED;
 728                }
 729        }
 730
 731        return 0;
 732}
 733
 734int iscsit_recover_dataout_sequence(
 735        struct iscsit_cmd *cmd,
 736        u32 pdu_offset,
 737        u32 pdu_length)
 738{
 739        u32 r2t_length = 0, r2t_offset = 0;
 740
 741        spin_lock_bh(&cmd->istate_lock);
 742        cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
 743        spin_unlock_bh(&cmd->istate_lock);
 744
 745        if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
 746                        &r2t_offset, &r2t_length) < 0)
 747                return DATAOUT_CANNOT_RECOVER;
 748
 749        iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length);
 750
 751        return DATAOUT_WITHIN_COMMAND_RECOVERY;
 752}
 753
 754static struct iscsi_ooo_cmdsn *iscsit_allocate_ooo_cmdsn(void)
 755{
 756        struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL;
 757
 758        ooo_cmdsn = kmem_cache_zalloc(lio_ooo_cache, GFP_ATOMIC);
 759        if (!ooo_cmdsn) {
 760                pr_err("Unable to allocate memory for"
 761                        " struct iscsi_ooo_cmdsn.\n");
 762                return NULL;
 763        }
 764        INIT_LIST_HEAD(&ooo_cmdsn->ooo_list);
 765
 766        return ooo_cmdsn;
 767}
 768
 769static int iscsit_attach_ooo_cmdsn(
 770        struct iscsit_session *sess,
 771        struct iscsi_ooo_cmdsn *ooo_cmdsn)
 772{
 773        struct iscsi_ooo_cmdsn *ooo_tail, *ooo_tmp;
 774
 775        lockdep_assert_held(&sess->cmdsn_mutex);
 776
 777        /*
 778         * We attach the struct iscsi_ooo_cmdsn entry to the out of order
 779         * list in increasing CmdSN order.
 780         * This allows iscsi_execute_ooo_cmdsns() to detect any
 781         * additional CmdSN holes while performing delayed execution.
 782         */
 783        if (list_empty(&sess->sess_ooo_cmdsn_list))
 784                list_add_tail(&ooo_cmdsn->ooo_list,
 785                                &sess->sess_ooo_cmdsn_list);
 786        else {
 787                ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
 788                                typeof(*ooo_tail), ooo_list);
 789                /*
 790                 * CmdSN is greater than the tail of the list.
 791                 */
 792                if (iscsi_sna_lt(ooo_tail->cmdsn, ooo_cmdsn->cmdsn))
 793                        list_add_tail(&ooo_cmdsn->ooo_list,
 794                                        &sess->sess_ooo_cmdsn_list);
 795                else {
 796                        /*
 797                         * CmdSN is either lower than the head,  or somewhere
 798                         * in the middle.
 799                         */
 800                        list_for_each_entry(ooo_tmp, &sess->sess_ooo_cmdsn_list,
 801                                                ooo_list) {
 802                                if (iscsi_sna_lt(ooo_tmp->cmdsn, ooo_cmdsn->cmdsn))
 803                                        continue;
 804
 805                                /* Insert before this entry */
 806                                list_add(&ooo_cmdsn->ooo_list,
 807                                        ooo_tmp->ooo_list.prev);
 808                                break;
 809                        }
 810                }
 811        }
 812
 813        return 0;
 814}
 815
 816/*
 817 *      Removes an struct iscsi_ooo_cmdsn from a session's list,
 818 *      called with struct iscsit_session->cmdsn_mutex held.
 819 */
 820void iscsit_remove_ooo_cmdsn(
 821        struct iscsit_session *sess,
 822        struct iscsi_ooo_cmdsn *ooo_cmdsn)
 823{
 824        list_del(&ooo_cmdsn->ooo_list);
 825        kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
 826}
 827
 828void iscsit_clear_ooo_cmdsns_for_conn(struct iscsit_conn *conn)
 829{
 830        struct iscsi_ooo_cmdsn *ooo_cmdsn;
 831        struct iscsit_session *sess = conn->sess;
 832
 833        mutex_lock(&sess->cmdsn_mutex);
 834        list_for_each_entry(ooo_cmdsn, &sess->sess_ooo_cmdsn_list, ooo_list) {
 835                if (ooo_cmdsn->cid != conn->cid)
 836                        continue;
 837
 838                ooo_cmdsn->cmd = NULL;
 839        }
 840        mutex_unlock(&sess->cmdsn_mutex);
 841}
 842
 843int iscsit_execute_ooo_cmdsns(struct iscsit_session *sess)
 844{
 845        int ooo_count = 0;
 846        struct iscsit_cmd *cmd = NULL;
 847        struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
 848
 849        lockdep_assert_held(&sess->cmdsn_mutex);
 850
 851        list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
 852                                &sess->sess_ooo_cmdsn_list, ooo_list) {
 853                if (ooo_cmdsn->cmdsn != sess->exp_cmd_sn)
 854                        continue;
 855
 856                if (!ooo_cmdsn->cmd) {
 857                        sess->exp_cmd_sn++;
 858                        iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
 859                        continue;
 860                }
 861
 862                cmd = ooo_cmdsn->cmd;
 863                cmd->i_state = cmd->deferred_i_state;
 864                ooo_count++;
 865                sess->exp_cmd_sn++;
 866                pr_debug("Executing out of order CmdSN: 0x%08x,"
 867                        " incremented ExpCmdSN to 0x%08x.\n",
 868                        cmd->cmd_sn, sess->exp_cmd_sn);
 869
 870                iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
 871
 872                if (iscsit_execute_cmd(cmd, 1) < 0)
 873                        return -1;
 874        }
 875
 876        return ooo_count;
 877}
 878
 879/*
 880 *      Called either:
 881 *
 882 *      1. With sess->cmdsn_mutex held from iscsi_execute_ooo_cmdsns()
 883 *      or iscsi_check_received_cmdsn().
 884 *      2. With no locks held directly from iscsi_handle_XXX_pdu() functions
 885 *      for immediate commands.
 886 */
 887int iscsit_execute_cmd(struct iscsit_cmd *cmd, int ooo)
 888{
 889        struct se_cmd *se_cmd = &cmd->se_cmd;
 890        struct iscsit_conn *conn = cmd->conn;
 891        int lr = 0;
 892
 893        spin_lock_bh(&cmd->istate_lock);
 894        if (ooo)
 895                cmd->cmd_flags &= ~ICF_OOO_CMDSN;
 896
 897        switch (cmd->iscsi_opcode) {
 898        case ISCSI_OP_SCSI_CMD:
 899                /*
 900                 * Go ahead and send the CHECK_CONDITION status for
 901                 * any SCSI CDB exceptions that may have occurred.
 902                 */
 903                if (cmd->sense_reason) {
 904                        if (cmd->sense_reason == TCM_RESERVATION_CONFLICT) {
 905                                cmd->i_state = ISTATE_SEND_STATUS;
 906                                spin_unlock_bh(&cmd->istate_lock);
 907                                iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
 908                                                cmd->i_state);
 909                                return 0;
 910                        }
 911                        spin_unlock_bh(&cmd->istate_lock);
 912                        if (cmd->se_cmd.transport_state & CMD_T_ABORTED)
 913                                return 0;
 914                        return transport_send_check_condition_and_sense(se_cmd,
 915                                        cmd->sense_reason, 0);
 916                }
 917                /*
 918                 * Special case for delayed CmdSN with Immediate
 919                 * Data and/or Unsolicited Data Out attached.
 920                 */
 921                if (cmd->immediate_data) {
 922                        if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
 923                                spin_unlock_bh(&cmd->istate_lock);
 924                                target_execute_cmd(&cmd->se_cmd);
 925                                return 0;
 926                        }
 927                        spin_unlock_bh(&cmd->istate_lock);
 928
 929                        if (!(cmd->cmd_flags &
 930                                        ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
 931                                if (cmd->se_cmd.transport_state & CMD_T_ABORTED)
 932                                        return 0;
 933
 934                                iscsit_set_dataout_sequence_values(cmd);
 935                                conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
 936                        }
 937                        return 0;
 938                }
 939                /*
 940                 * The default handler.
 941                 */
 942                spin_unlock_bh(&cmd->istate_lock);
 943
 944                if ((cmd->data_direction == DMA_TO_DEVICE) &&
 945                    !(cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
 946                        if (cmd->se_cmd.transport_state & CMD_T_ABORTED)
 947                                return 0;
 948
 949                        iscsit_set_unsolicited_dataout(cmd);
 950                }
 951                return transport_handle_cdb_direct(&cmd->se_cmd);
 952
 953        case ISCSI_OP_NOOP_OUT:
 954        case ISCSI_OP_TEXT:
 955                spin_unlock_bh(&cmd->istate_lock);
 956                iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
 957                break;
 958        case ISCSI_OP_SCSI_TMFUNC:
 959                if (cmd->se_cmd.se_tmr_req->response) {
 960                        spin_unlock_bh(&cmd->istate_lock);
 961                        iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
 962                                        cmd->i_state);
 963                        return 0;
 964                }
 965                spin_unlock_bh(&cmd->istate_lock);
 966
 967                return transport_generic_handle_tmr(&cmd->se_cmd);
 968        case ISCSI_OP_LOGOUT:
 969                spin_unlock_bh(&cmd->istate_lock);
 970                switch (cmd->logout_reason) {
 971                case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
 972                        lr = iscsit_logout_closesession(cmd, cmd->conn);
 973                        break;
 974                case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
 975                        lr = iscsit_logout_closeconnection(cmd, cmd->conn);
 976                        break;
 977                case ISCSI_LOGOUT_REASON_RECOVERY:
 978                        lr = iscsit_logout_removeconnforrecovery(cmd, cmd->conn);
 979                        break;
 980                default:
 981                        pr_err("Unknown iSCSI Logout Request Code:"
 982                                " 0x%02x\n", cmd->logout_reason);
 983                        return -1;
 984                }
 985
 986                return lr;
 987        default:
 988                spin_unlock_bh(&cmd->istate_lock);
 989                pr_err("Cannot perform out of order execution for"
 990                " unknown iSCSI Opcode: 0x%02x\n", cmd->iscsi_opcode);
 991                return -1;
 992        }
 993
 994        return 0;
 995}
 996
 997void iscsit_free_all_ooo_cmdsns(struct iscsit_session *sess)
 998{
 999        struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
1000
1001        mutex_lock(&sess->cmdsn_mutex);
1002        list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
1003                        &sess->sess_ooo_cmdsn_list, ooo_list) {
1004
1005                list_del(&ooo_cmdsn->ooo_list);
1006                kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
1007        }
1008        mutex_unlock(&sess->cmdsn_mutex);
1009}
1010
1011int iscsit_handle_ooo_cmdsn(
1012        struct iscsit_session *sess,
1013        struct iscsit_cmd *cmd,
1014        u32 cmdsn)
1015{
1016        int batch = 0;
1017        struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL, *ooo_tail = NULL;
1018
1019        cmd->deferred_i_state           = cmd->i_state;
1020        cmd->i_state                    = ISTATE_DEFERRED_CMD;
1021        cmd->cmd_flags                  |= ICF_OOO_CMDSN;
1022
1023        if (list_empty(&sess->sess_ooo_cmdsn_list))
1024                batch = 1;
1025        else {
1026                ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
1027                                typeof(*ooo_tail), ooo_list);
1028                if (ooo_tail->cmdsn != (cmdsn - 1))
1029                        batch = 1;
1030        }
1031
1032        ooo_cmdsn = iscsit_allocate_ooo_cmdsn();
1033        if (!ooo_cmdsn)
1034                return -ENOMEM;
1035
1036        ooo_cmdsn->cmd                  = cmd;
1037        ooo_cmdsn->batch_count          = (batch) ?
1038                                          (cmdsn - sess->exp_cmd_sn) : 1;
1039        ooo_cmdsn->cid                  = cmd->conn->cid;
1040        ooo_cmdsn->exp_cmdsn            = sess->exp_cmd_sn;
1041        ooo_cmdsn->cmdsn                = cmdsn;
1042
1043        if (iscsit_attach_ooo_cmdsn(sess, ooo_cmdsn) < 0) {
1044                kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
1045                return -ENOMEM;
1046        }
1047
1048        return 0;
1049}
1050
1051static int iscsit_set_dataout_timeout_values(
1052        struct iscsit_cmd *cmd,
1053        u32 *offset,
1054        u32 *length)
1055{
1056        struct iscsit_conn *conn = cmd->conn;
1057        struct iscsi_r2t *r2t;
1058
1059        if (cmd->unsolicited_data) {
1060                *offset = 0;
1061                *length = (conn->sess->sess_ops->FirstBurstLength >
1062                           cmd->se_cmd.data_length) ?
1063                           cmd->se_cmd.data_length :
1064                           conn->sess->sess_ops->FirstBurstLength;
1065                return 0;
1066        }
1067
1068        spin_lock_bh(&cmd->r2t_lock);
1069        if (list_empty(&cmd->cmd_r2t_list)) {
1070                pr_err("cmd->cmd_r2t_list is empty!\n");
1071                spin_unlock_bh(&cmd->r2t_lock);
1072                return -1;
1073        }
1074
1075        list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
1076                if (r2t->sent_r2t && !r2t->recovery_r2t && !r2t->seq_complete) {
1077                        *offset = r2t->offset;
1078                        *length = r2t->xfer_len;
1079                        spin_unlock_bh(&cmd->r2t_lock);
1080                        return 0;
1081                }
1082        }
1083        spin_unlock_bh(&cmd->r2t_lock);
1084
1085        pr_err("Unable to locate any incomplete DataOUT"
1086                " sequences for ITT: 0x%08x.\n", cmd->init_task_tag);
1087
1088        return -1;
1089}
1090
1091/*
1092 *      NOTE: Called from interrupt (timer) context.
1093 */
1094void iscsit_handle_dataout_timeout(struct timer_list *t)
1095{
1096        u32 pdu_length = 0, pdu_offset = 0;
1097        u32 r2t_length = 0, r2t_offset = 0;
1098        struct iscsit_cmd *cmd = from_timer(cmd, t, dataout_timer);
1099        struct iscsit_conn *conn = cmd->conn;
1100        struct iscsit_session *sess = NULL;
1101        struct iscsi_node_attrib *na;
1102
1103        iscsit_inc_conn_usage_count(conn);
1104
1105        spin_lock_bh(&cmd->dataout_timeout_lock);
1106        if (cmd->dataout_timer_flags & ISCSI_TF_STOP) {
1107                spin_unlock_bh(&cmd->dataout_timeout_lock);
1108                iscsit_dec_conn_usage_count(conn);
1109                return;
1110        }
1111        cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1112        sess = conn->sess;
1113        na = iscsit_tpg_get_node_attrib(sess);
1114
1115        if (!sess->sess_ops->ErrorRecoveryLevel) {
1116                pr_err("Unable to recover from DataOut timeout while"
1117                        " in ERL=0, closing iSCSI connection for I_T Nexus"
1118                        " %s,i,0x%6phN,%s,t,0x%02x\n",
1119                        sess->sess_ops->InitiatorName, sess->isid,
1120                        sess->tpg->tpg_tiqn->tiqn, (u32)sess->tpg->tpgt);
1121                goto failure;
1122        }
1123
1124        if (++cmd->dataout_timeout_retries == na->dataout_timeout_retries) {
1125                pr_err("Command ITT: 0x%08x exceeded max retries"
1126                        " for DataOUT timeout %u, closing iSCSI connection for"
1127                        " I_T Nexus %s,i,0x%6phN,%s,t,0x%02x\n",
1128                        cmd->init_task_tag, na->dataout_timeout_retries,
1129                        sess->sess_ops->InitiatorName, sess->isid,
1130                        sess->tpg->tpg_tiqn->tiqn, (u32)sess->tpg->tpgt);
1131                goto failure;
1132        }
1133
1134        cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
1135
1136        if (conn->sess->sess_ops->DataSequenceInOrder) {
1137                if (conn->sess->sess_ops->DataPDUInOrder) {
1138                        pdu_offset = cmd->write_data_done;
1139                        if ((pdu_offset + (conn->sess->sess_ops->MaxBurstLength -
1140                             cmd->next_burst_len)) > cmd->se_cmd.data_length)
1141                                pdu_length = (cmd->se_cmd.data_length -
1142                                        cmd->write_data_done);
1143                        else
1144                                pdu_length = (conn->sess->sess_ops->MaxBurstLength -
1145                                                cmd->next_burst_len);
1146                } else {
1147                        pdu_offset = cmd->seq_start_offset;
1148                        pdu_length = (cmd->seq_end_offset -
1149                                cmd->seq_start_offset);
1150                }
1151        } else {
1152                if (iscsit_set_dataout_timeout_values(cmd, &pdu_offset,
1153                                &pdu_length) < 0)
1154                        goto failure;
1155        }
1156
1157        if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
1158                        &r2t_offset, &r2t_length) < 0)
1159                goto failure;
1160
1161        pr_debug("Command ITT: 0x%08x timed out waiting for"
1162                " completion of %sDataOUT Sequence Offset: %u, Length: %u\n",
1163                cmd->init_task_tag, (cmd->unsolicited_data) ? "Unsolicited " :
1164                "", r2t_offset, r2t_length);
1165
1166        if (iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length) < 0)
1167                goto failure;
1168
1169        iscsit_start_dataout_timer(cmd, conn);
1170        spin_unlock_bh(&cmd->dataout_timeout_lock);
1171        iscsit_dec_conn_usage_count(conn);
1172
1173        return;
1174
1175failure:
1176        spin_unlock_bh(&cmd->dataout_timeout_lock);
1177        iscsit_fill_cxn_timeout_err_stats(sess);
1178        iscsit_cause_connection_reinstatement(conn, 0);
1179        iscsit_dec_conn_usage_count(conn);
1180}
1181
1182void iscsit_mod_dataout_timer(struct iscsit_cmd *cmd)
1183{
1184        struct iscsit_conn *conn = cmd->conn;
1185        struct iscsit_session *sess = conn->sess;
1186        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1187
1188        spin_lock_bh(&cmd->dataout_timeout_lock);
1189        if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
1190                spin_unlock_bh(&cmd->dataout_timeout_lock);
1191                return;
1192        }
1193
1194        mod_timer(&cmd->dataout_timer,
1195                (get_jiffies_64() + na->dataout_timeout * HZ));
1196        pr_debug("Updated DataOUT timer for ITT: 0x%08x",
1197                        cmd->init_task_tag);
1198        spin_unlock_bh(&cmd->dataout_timeout_lock);
1199}
1200
1201void iscsit_start_dataout_timer(
1202        struct iscsit_cmd *cmd,
1203        struct iscsit_conn *conn)
1204{
1205        struct iscsit_session *sess = conn->sess;
1206        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1207
1208        lockdep_assert_held(&cmd->dataout_timeout_lock);
1209
1210        if (cmd->dataout_timer_flags & ISCSI_TF_RUNNING)
1211                return;
1212
1213        pr_debug("Starting DataOUT timer for ITT: 0x%08x on"
1214                " CID: %hu.\n", cmd->init_task_tag, conn->cid);
1215
1216        cmd->dataout_timer_flags &= ~ISCSI_TF_STOP;
1217        cmd->dataout_timer_flags |= ISCSI_TF_RUNNING;
1218        mod_timer(&cmd->dataout_timer, jiffies + na->dataout_timeout * HZ);
1219}
1220
1221void iscsit_stop_dataout_timer(struct iscsit_cmd *cmd)
1222{
1223        spin_lock_bh(&cmd->dataout_timeout_lock);
1224        if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
1225                spin_unlock_bh(&cmd->dataout_timeout_lock);
1226                return;
1227        }
1228        cmd->dataout_timer_flags |= ISCSI_TF_STOP;
1229        spin_unlock_bh(&cmd->dataout_timeout_lock);
1230
1231        del_timer_sync(&cmd->dataout_timer);
1232
1233        spin_lock_bh(&cmd->dataout_timeout_lock);
1234        cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1235        pr_debug("Stopped DataOUT Timer for ITT: 0x%08x\n",
1236                        cmd->init_task_tag);
1237        spin_unlock_bh(&cmd->dataout_timeout_lock);
1238}
1239EXPORT_SYMBOL(iscsit_stop_dataout_timer);
1240