drivers/target/iscsi/iscsi_target_erl0.c

   1 /******************************************************************************
   2  * This file contains error recovery level zero functions used by
   3  * the iSCSI Target driver.
   4  *
   5  * (c) Copyright 2007-2013 Datera, Inc.
   6  *
   7  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  ******************************************************************************/
  19
  20 #include <scsi/iscsi_proto.h>
  21 #include <target/target_core_base.h>
  22 #include <target/target_core_fabric.h>
  23
  24 #include <target/iscsi/iscsi_target_core.h>
  25 #include "iscsi_target_seq_pdu_list.h"
  26 #include "iscsi_target_tq.h"
  27 #include "iscsi_target_erl0.h"
  28 #include "iscsi_target_erl1.h"
  29 #include "iscsi_target_erl2.h"
  30 #include "iscsi_target_util.h"
  31 #include "iscsi_target.h"
  32
  33 /*
  34  *      Used to set values in struct iscsi_cmd that iscsit_dataout_check_sequence()
  35  *      checks against to determine a PDU's Offset+Length is within the current
  36  *      DataOUT Sequence.  Used for DataSequenceInOrder=Yes only.
  37  */
  38 void iscsit_set_dataout_sequence_values(
  39         struct iscsi_cmd *cmd)
  40 {
  41         struct iscsi_conn *conn = cmd->conn;
  42         /*
  43          * Still set seq_start_offset and seq_end_offset for Unsolicited
  44          * DataOUT, even if DataSequenceInOrder=No.
  45          */
  46         if (cmd->unsolicited_data) {
  47                 cmd->seq_start_offset = cmd->write_data_done;
  48                 cmd->seq_end_offset = (cmd->write_data_done +
  49                         ((cmd->se_cmd.data_length >
  50                           conn->sess->sess_ops->FirstBurstLength) ?
  51                          conn->sess->sess_ops->FirstBurstLength : cmd->se_cmd.data_length));
  52                 return;
  53         }
  54
  55         if (!conn->sess->sess_ops->DataSequenceInOrder)
  56                 return;
  57
  58         if (!cmd->seq_start_offset && !cmd->seq_end_offset) {
  59                 cmd->seq_start_offset = cmd->write_data_done;
  60                 cmd->seq_end_offset = (cmd->se_cmd.data_length >
  61                         conn->sess->sess_ops->MaxBurstLength) ?
  62                         (cmd->write_data_done +
  63                         conn->sess->sess_ops->MaxBurstLength) : cmd->se_cmd.data_length;
  64         } else {
  65                 cmd->seq_start_offset = cmd->seq_end_offset;
  66                 cmd->seq_end_offset = ((cmd->seq_end_offset +
  67                         conn->sess->sess_ops->MaxBurstLength) >=
  68                         cmd->se_cmd.data_length) ? cmd->se_cmd.data_length :
  69                         (cmd->seq_end_offset +
  70                          conn->sess->sess_ops->MaxBurstLength);
  71         }
  72 }
  73
  74 static int iscsit_dataout_within_command_recovery_check(
  75         struct iscsi_cmd *cmd,
  76         unsigned char *buf)
  77 {
  78         struct iscsi_conn *conn = cmd->conn;
  79         struct iscsi_data *hdr = (struct iscsi_data *) buf;
  80         u32 payload_length = ntoh24(hdr->dlength);
  81
  82         /*
  83          * We do the within-command recovery checks here as it is
  84          * the first function called in iscsi_check_pre_dataout().
  85          * Basically, if we are in within-command recovery and
  86          * the PDU does not contain the offset the sequence needs,
  87          * dump the payload.
  88          *
  89          * This only applies to DataPDUInOrder=Yes, for
  90          * DataPDUInOrder=No we only re-request the failed PDU
  91          * and check that all PDUs in a sequence are received
  92          * upon end of sequence.
  93          */
  94         if (conn->sess->sess_ops->DataSequenceInOrder) {
  95                 if ((cmd->cmd_flags & ICF_WITHIN_COMMAND_RECOVERY) &&
  96                     cmd->write_data_done != be32_to_cpu(hdr->offset))
  97                         goto dump;
  98
  99                 cmd->cmd_flags &= ~ICF_WITHIN_COMMAND_RECOVERY;
 100         } else {
 101                 struct iscsi_seq *seq;
 102
 103                 seq = iscsit_get_seq_holder(cmd, be32_to_cpu(hdr->offset),
 104                                             payload_length);
 105                 if (!seq)
 106                         return DATAOUT_CANNOT_RECOVER;
 107                 /*
 108                  * Set the struct iscsi_seq pointer to reuse later.
 109                  */
 110                 cmd->seq_ptr = seq;
 111
 112                 if (conn->sess->sess_ops->DataPDUInOrder) {
 113                         if (seq->status ==
 114                             DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY &&
 115                            (seq->offset != be32_to_cpu(hdr->offset) ||
 116                             seq->data_sn != be32_to_cpu(hdr->datasn)))
 117                                 goto dump;
 118                 } else {
 119                         if (seq->status ==
 120                              DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY &&
 121                             seq->data_sn != be32_to_cpu(hdr->datasn))
 122                                 goto dump;
 123                 }
 124
 125                 if (seq->status == DATAOUT_SEQUENCE_COMPLETE)
 126                         goto dump;
 127
 128                 if (seq->status != DATAOUT_SEQUENCE_COMPLETE)
 129                         seq->status = 0;
 130         }
 131
 132         return DATAOUT_NORMAL;
 133
 134 dump:
 135         pr_err("Dumping DataOUT PDU Offset: %u Length: %d DataSN:"
 136                 " 0x%08x\n", hdr->offset, payload_length, hdr->datasn);
 137         return iscsit_dump_data_payload(conn, payload_length, 1);
 138 }
 139
 140 static int iscsit_dataout_check_unsolicited_sequence(
 141         struct iscsi_cmd *cmd,
 142         unsigned char *buf)
 143 {
 144         u32 first_burst_len;
 145         struct iscsi_conn *conn = cmd->conn;
 146         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 147         u32 payload_length = ntoh24(hdr->dlength);
 148
 149
 150         if ((be32_to_cpu(hdr->offset) < cmd->seq_start_offset) ||
 151            ((be32_to_cpu(hdr->offset) + payload_length) > cmd->seq_end_offset)) {
 152                 pr_err("Command ITT: 0x%08x with Offset: %u,"
 153                 " Length: %u outside of Unsolicited Sequence %u:%u while"
 154                 " DataSequenceInOrder=Yes.\n", cmd->init_task_tag,
 155                 be32_to_cpu(hdr->offset), payload_length, cmd->seq_start_offset,
 156                         cmd->seq_end_offset);
 157                 return DATAOUT_CANNOT_RECOVER;
 158         }
 159
 160         first_burst_len = (cmd->first_burst_len + payload_length);
 161
 162         if (first_burst_len > conn->sess->sess_ops->FirstBurstLength) {
 163                 pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 164                         " for this Unsolicited DataOut Burst.\n",
 165                         first_burst_len, conn->sess->sess_ops->FirstBurstLength);
 166                 transport_send_check_condition_and_sense(&cmd->se_cmd,
 167                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 168                 return DATAOUT_CANNOT_RECOVER;
 169         }
 170
 171         /*
 172          * Perform various MaxBurstLength and ISCSI_FLAG_CMD_FINAL sanity
 173          * checks for the current Unsolicited DataOUT Sequence.
 174          */
 175         if (hdr->flags & ISCSI_FLAG_CMD_FINAL) {
 176                 /*
 177                  * Ignore ISCSI_FLAG_CMD_FINAL checks while DataPDUInOrder=No, end of
 178                  * sequence checks are handled in
 179                  * iscsit_dataout_datapduinorder_no_fbit().
 180                  */
 181                 if (!conn->sess->sess_ops->DataPDUInOrder)
 182                         goto out;
 183
 184                 if ((first_burst_len != cmd->se_cmd.data_length) &&
 185                     (first_burst_len != conn->sess->sess_ops->FirstBurstLength)) {
 186                         pr_err("Unsolicited non-immediate data"
 187                         " received %u does not equal FirstBurstLength: %u, and"
 188                         " does not equal ExpXferLen %u.\n", first_burst_len,
 189                                 conn->sess->sess_ops->FirstBurstLength,
 190                                 cmd->se_cmd.data_length);
 191                         transport_send_check_condition_and_sense(&cmd->se_cmd,
 192                                         TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 193                         return DATAOUT_CANNOT_RECOVER;
 194                 }
 195         } else {
 196                 if (first_burst_len == conn->sess->sess_ops->FirstBurstLength) {
 197                         pr_err("Command ITT: 0x%08x reached"
 198                         " FirstBurstLength: %u, but ISCSI_FLAG_CMD_FINAL is not set. protocol"
 199                                 " error.\n", cmd->init_task_tag,
 200                                 conn->sess->sess_ops->FirstBurstLength);
 201                         return DATAOUT_CANNOT_RECOVER;
 202                 }
 203                 if (first_burst_len == cmd->se_cmd.data_length) {
 204                         pr_err("Command ITT: 0x%08x reached"
 205                         " ExpXferLen: %u, but ISCSI_FLAG_CMD_FINAL is not set. protocol"
 206                         " error.\n", cmd->init_task_tag, cmd->se_cmd.data_length);
 207                         return DATAOUT_CANNOT_RECOVER;
 208                 }
 209         }
 210
 211 out:
 212         return DATAOUT_NORMAL;
 213 }
 214
 215 static int iscsit_dataout_check_sequence(
 216         struct iscsi_cmd *cmd,
 217         unsigned char *buf)
 218 {
 219         u32 next_burst_len;
 220         struct iscsi_conn *conn = cmd->conn;
 221         struct iscsi_seq *seq = NULL;
 222         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 223         u32 payload_length = ntoh24(hdr->dlength);
 224
 225         /*
 226          * For DataSequenceInOrder=Yes: Check that the offset and offset+length
 227          * is within range as defined by iscsi_set_dataout_sequence_values().
 228          *
 229          * For DataSequenceInOrder=No: Check that an struct iscsi_seq exists for
 230          * offset+length tuple.
 231          */
 232         if (conn->sess->sess_ops->DataSequenceInOrder) {
 233                 /*
 234                  * Due to possibility of recovery DataOUT sent by the initiator
 235                  * fullfilling an Recovery R2T, it's best to just dump the
 236                  * payload here, instead of erroring out.
 237                  */
 238                 if ((be32_to_cpu(hdr->offset) < cmd->seq_start_offset) ||
 239                    ((be32_to_cpu(hdr->offset) + payload_length) > cmd->seq_end_offset)) {
 240                         pr_err("Command ITT: 0x%08x with Offset: %u,"
 241                         " Length: %u outside of Sequence %u:%u while"
 242                         " DataSequenceInOrder=Yes.\n", cmd->init_task_tag,
 243                         be32_to_cpu(hdr->offset), payload_length, cmd->seq_start_offset,
 244                                 cmd->seq_end_offset);
 245
 246                         if (iscsit_dump_data_payload(conn, payload_length, 1) < 0)
 247                                 return DATAOUT_CANNOT_RECOVER;
 248                         return DATAOUT_WITHIN_COMMAND_RECOVERY;
 249                 }
 250
 251                 next_burst_len = (cmd->next_burst_len + payload_length);
 252         } else {
 253                 seq = iscsit_get_seq_holder(cmd, be32_to_cpu(hdr->offset),
 254                                             payload_length);
 255                 if (!seq)
 256                         return DATAOUT_CANNOT_RECOVER;
 257                 /*
 258                  * Set the struct iscsi_seq pointer to reuse later.
 259                  */
 260                 cmd->seq_ptr = seq;
 261
 262                 if (seq->status == DATAOUT_SEQUENCE_COMPLETE) {
 263                         if (iscsit_dump_data_payload(conn, payload_length, 1) < 0)
 264                                 return DATAOUT_CANNOT_RECOVER;
 265                         return DATAOUT_WITHIN_COMMAND_RECOVERY;
 266                 }
 267
 268                 next_burst_len = (seq->next_burst_len + payload_length);
 269         }
 270
 271         if (next_burst_len > conn->sess->sess_ops->MaxBurstLength) {
 272                 pr_err("Command ITT: 0x%08x, NextBurstLength: %u and"
 273                         " Length: %u exceeds MaxBurstLength: %u. protocol"
 274                         " error.\n", cmd->init_task_tag,
 275                         (next_burst_len - payload_length),
 276                         payload_length, conn->sess->sess_ops->MaxBurstLength);
 277                 return DATAOUT_CANNOT_RECOVER;
 278         }
 279
 280         /*
 281          * Perform various MaxBurstLength and ISCSI_FLAG_CMD_FINAL sanity
 282          * checks for the current DataOUT Sequence.
 283          */
 284         if (hdr->flags & ISCSI_FLAG_CMD_FINAL) {
 285                 /*
 286                  * Ignore ISCSI_FLAG_CMD_FINAL checks while DataPDUInOrder=No, end of
 287                  * sequence checks are handled in
 288                  * iscsit_dataout_datapduinorder_no_fbit().
 289                  */
 290                 if (!conn->sess->sess_ops->DataPDUInOrder)
 291                         goto out;
 292
 293                 if (conn->sess->sess_ops->DataSequenceInOrder) {
 294                         if ((next_burst_len <
 295                              conn->sess->sess_ops->MaxBurstLength) &&
 296                            ((cmd->write_data_done + payload_length) <
 297                              cmd->se_cmd.data_length)) {
 298                                 pr_err("Command ITT: 0x%08x set ISCSI_FLAG_CMD_FINAL"
 299                                 " before end of DataOUT sequence, protocol"
 300                                 " error.\n", cmd->init_task_tag);
 301                                 return DATAOUT_CANNOT_RECOVER;
 302                         }
 303                 } else {
 304                         if (next_burst_len < seq->xfer_len) {
 305                                 pr_err("Command ITT: 0x%08x set ISCSI_FLAG_CMD_FINAL"
 306                                 " before end of DataOUT sequence, protocol"
 307                                 " error.\n", cmd->init_task_tag);
 308                                 return DATAOUT_CANNOT_RECOVER;
 309                         }
 310                 }
 311         } else {
 312                 if (conn->sess->sess_ops->DataSequenceInOrder) {
 313                         if (next_burst_len ==
 314                                         conn->sess->sess_ops->MaxBurstLength) {
 315                                 pr_err("Command ITT: 0x%08x reached"
 316                                 " MaxBurstLength: %u, but ISCSI_FLAG_CMD_FINAL is"
 317                                 " not set, protocol error.", cmd->init_task_tag,
 318                                         conn->sess->sess_ops->MaxBurstLength);
 319                                 return DATAOUT_CANNOT_RECOVER;
 320                         }
 321                         if ((cmd->write_data_done + payload_length) ==
 322                                         cmd->se_cmd.data_length) {
 323                                 pr_err("Command ITT: 0x%08x reached"
 324                                 " last DataOUT PDU in sequence but ISCSI_FLAG_"
 325                                 "CMD_FINAL is not set, protocol error.\n",
 326                                         cmd->init_task_tag);
 327                                 return DATAOUT_CANNOT_RECOVER;
 328                         }
 329                 } else {
 330                         if (next_burst_len == seq->xfer_len) {
 331                                 pr_err("Command ITT: 0x%08x reached"
 332                                 " last DataOUT PDU in sequence but ISCSI_FLAG_"
 333                                 "CMD_FINAL is not set, protocol error.\n",
 334                                         cmd->init_task_tag);
 335                                 return DATAOUT_CANNOT_RECOVER;
 336                         }
 337                 }
 338         }
 339
 340 out:
 341         return DATAOUT_NORMAL;
 342 }
 343
 344 static int iscsit_dataout_check_datasn(
 345         struct iscsi_cmd *cmd,
 346         unsigned char *buf)
 347 {
 348         u32 data_sn = 0;
 349         struct iscsi_conn *conn = cmd->conn;
 350         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 351         u32 payload_length = ntoh24(hdr->dlength);
 352
 353         /*
 354          * Considering the target has no method of re-requesting DataOUT
 355          * by DataSN, if we receieve a greater DataSN than expected we
 356          * assume the functions for DataPDUInOrder=[Yes,No] below will
 357          * handle it.
 358          *
 359          * If the DataSN is less than expected, dump the payload.
 360          */
 361         if (conn->sess->sess_ops->DataSequenceInOrder)
 362                 data_sn = cmd->data_sn;
 363         else {
 364                 struct iscsi_seq *seq = cmd->seq_ptr;
 365                 data_sn = seq->data_sn;
 366         }
 367
 368         if (be32_to_cpu(hdr->datasn) > data_sn) {
 369                 pr_err("Command ITT: 0x%08x, received DataSN: 0x%08x"
 370                         " higher than expected 0x%08x.\n", cmd->init_task_tag,
 371                                 be32_to_cpu(hdr->datasn), data_sn);
 372                 goto recover;
 373         } else if (be32_to_cpu(hdr->datasn) < data_sn) {
 374                 pr_err("Command ITT: 0x%08x, received DataSN: 0x%08x"
 375                         " lower than expected 0x%08x, discarding payload.\n",
 376                         cmd->init_task_tag, be32_to_cpu(hdr->datasn), data_sn);
 377                 goto dump;
 378         }
 379
 380         return DATAOUT_NORMAL;
 381
 382 recover:
 383         if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
 384                 pr_err("Unable to perform within-command recovery"
 385                                 " while ERL=0.\n");
 386                 return DATAOUT_CANNOT_RECOVER;
 387         }
 388 dump:
 389         if (iscsit_dump_data_payload(conn, payload_length, 1) < 0)
 390                 return DATAOUT_CANNOT_RECOVER;
 391
 392         return DATAOUT_WITHIN_COMMAND_RECOVERY;
 393 }
 394
 395 static int iscsit_dataout_pre_datapduinorder_yes(
 396         struct iscsi_cmd *cmd,
 397         unsigned char *buf)
 398 {
 399         int dump = 0, recovery = 0;
 400         struct iscsi_conn *conn = cmd->conn;
 401         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 402         u32 payload_length = ntoh24(hdr->dlength);
 403
 404         /*
 405          * For DataSequenceInOrder=Yes: If the offset is greater than the global
 406          * DataPDUInOrder=Yes offset counter in struct iscsi_cmd a protcol error has
 407          * occurred and fail the connection.
 408          *
 409          * For DataSequenceInOrder=No: If the offset is greater than the per
 410          * sequence DataPDUInOrder=Yes offset counter in struct iscsi_seq a protocol
 411          * error has occurred and fail the connection.
 412          */
 413         if (conn->sess->sess_ops->DataSequenceInOrder) {
 414                 if (be32_to_cpu(hdr->offset) != cmd->write_data_done) {
 415                         pr_err("Command ITT: 0x%08x, received offset"
 416                         " %u different than expected %u.\n", cmd->init_task_tag,
 417                                 be32_to_cpu(hdr->offset), cmd->write_data_done);
 418                         recovery = 1;
 419                         goto recover;
 420                 }
 421         } else {
 422                 struct iscsi_seq *seq = cmd->seq_ptr;
 423
 424                 if (be32_to_cpu(hdr->offset) > seq->offset) {
 425                         pr_err("Command ITT: 0x%08x, received offset"
 426                         " %u greater than expected %u.\n", cmd->init_task_tag,
 427                                 be32_to_cpu(hdr->offset), seq->offset);
 428                         recovery = 1;
 429                         goto recover;
 430                 } else if (be32_to_cpu(hdr->offset) < seq->offset) {
 431                         pr_err("Command ITT: 0x%08x, received offset"
 432                         " %u less than expected %u, discarding payload.\n",
 433                                 cmd->init_task_tag, be32_to_cpu(hdr->offset),
 434                                 seq->offset);
 435                         dump = 1;
 436                         goto dump;
 437                 }
 438         }
 439
 440         return DATAOUT_NORMAL;
 441
 442 recover:
 443         if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
 444                 pr_err("Unable to perform within-command recovery"
 445                                 " while ERL=0.\n");
 446                 return DATAOUT_CANNOT_RECOVER;
 447         }
 448 dump:
 449         if (iscsit_dump_data_payload(conn, payload_length, 1) < 0)
 450                 return DATAOUT_CANNOT_RECOVER;
 451
 452         return (recovery) ? iscsit_recover_dataout_sequence(cmd,
 453                 be32_to_cpu(hdr->offset), payload_length) :
 454                (dump) ? DATAOUT_WITHIN_COMMAND_RECOVERY : DATAOUT_NORMAL;
 455 }
 456
 457 static int iscsit_dataout_pre_datapduinorder_no(
 458         struct iscsi_cmd *cmd,
 459         unsigned char *buf)
 460 {
 461         struct iscsi_pdu *pdu;
 462         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 463         u32 payload_length = ntoh24(hdr->dlength);
 464
 465         pdu = iscsit_get_pdu_holder(cmd, be32_to_cpu(hdr->offset),
 466                                     payload_length);
 467         if (!pdu)
 468                 return DATAOUT_CANNOT_RECOVER;
 469
 470         cmd->pdu_ptr = pdu;
 471
 472         switch (pdu->status) {
 473         case ISCSI_PDU_NOT_RECEIVED:
 474         case ISCSI_PDU_CRC_FAILED:
 475         case ISCSI_PDU_TIMED_OUT:
 476                 break;
 477         case ISCSI_PDU_RECEIVED_OK:
 478                 pr_err("Command ITT: 0x%08x received already gotten"
 479                         " Offset: %u, Length: %u\n", cmd->init_task_tag,
 480                                 be32_to_cpu(hdr->offset), payload_length);
 481                 return iscsit_dump_data_payload(cmd->conn, payload_length, 1);
 482         default:
 483                 return DATAOUT_CANNOT_RECOVER;
 484         }
 485
 486         return DATAOUT_NORMAL;
 487 }
 488
 489 static int iscsit_dataout_update_r2t(struct iscsi_cmd *cmd, u32 offset, u32 length)
 490 {
 491         struct iscsi_r2t *r2t;
 492
 493         if (cmd->unsolicited_data)
 494                 return 0;
 495
 496         r2t = iscsit_get_r2t_for_eos(cmd, offset, length);
 497         if (!r2t)
 498                 return -1;
 499
 500         spin_lock_bh(&cmd->r2t_lock);
 501         r2t->seq_complete = 1;
 502         cmd->outstanding_r2ts--;
 503         spin_unlock_bh(&cmd->r2t_lock);
 504
 505         return 0;
 506 }
 507
 508 static int iscsit_dataout_update_datapduinorder_no(
 509         struct iscsi_cmd *cmd,
 510         u32 data_sn,
 511         int f_bit)
 512 {
 513         int ret = 0;
 514         struct iscsi_pdu *pdu = cmd->pdu_ptr;
 515
 516         pdu->data_sn = data_sn;
 517
 518         switch (pdu->status) {
 519         case ISCSI_PDU_NOT_RECEIVED:
 520                 pdu->status = ISCSI_PDU_RECEIVED_OK;
 521                 break;
 522         case ISCSI_PDU_CRC_FAILED:
 523                 pdu->status = ISCSI_PDU_RECEIVED_OK;
 524                 break;
 525         case ISCSI_PDU_TIMED_OUT:
 526                 pdu->status = ISCSI_PDU_RECEIVED_OK;
 527                 break;
 528         default:
 529                 return DATAOUT_CANNOT_RECOVER;
 530         }
 531
 532         if (f_bit) {
 533                 ret = iscsit_dataout_datapduinorder_no_fbit(cmd, pdu);
 534                 if (ret == DATAOUT_CANNOT_RECOVER)
 535                         return ret;
 536         }
 537
 538         return DATAOUT_NORMAL;
 539 }
 540
 541 static int iscsit_dataout_post_crc_passed(
 542         struct iscsi_cmd *cmd,
 543         unsigned char *buf)
 544 {
 545         int ret, send_r2t = 0;
 546         struct iscsi_conn *conn = cmd->conn;
 547         struct iscsi_seq *seq = NULL;
 548         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 549         u32 payload_length = ntoh24(hdr->dlength);
 550
 551         if (cmd->unsolicited_data) {
 552                 if ((cmd->first_burst_len + payload_length) ==
 553                      conn->sess->sess_ops->FirstBurstLength) {
 554                         if (iscsit_dataout_update_r2t(cmd, be32_to_cpu(hdr->offset),
 555                                         payload_length) < 0)
 556                                 return DATAOUT_CANNOT_RECOVER;
 557                         send_r2t = 1;
 558                 }
 559
 560                 if (!conn->sess->sess_ops->DataPDUInOrder) {
 561                         ret = iscsit_dataout_update_datapduinorder_no(cmd,
 562                                 be32_to_cpu(hdr->datasn),
 563                                 (hdr->flags & ISCSI_FLAG_CMD_FINAL));
 564                         if (ret == DATAOUT_CANNOT_RECOVER)
 565                                 return ret;
 566                 }
 567
 568                 cmd->first_burst_len += payload_length;
 569
 570                 if (conn->sess->sess_ops->DataSequenceInOrder)
 571                         cmd->data_sn++;
 572                 else {
 573                         seq = cmd->seq_ptr;
 574                         seq->data_sn++;
 575                         seq->offset += payload_length;
 576                 }
 577
 578                 if (send_r2t) {
 579                         if (seq)
 580                                 seq->status = DATAOUT_SEQUENCE_COMPLETE;
 581                         cmd->first_burst_len = 0;
 582                         cmd->unsolicited_data = 0;
 583                 }
 584         } else {
 585                 if (conn->sess->sess_ops->DataSequenceInOrder) {
 586                         if ((cmd->next_burst_len + payload_length) ==
 587                              conn->sess->sess_ops->MaxBurstLength) {
 588                                 if (iscsit_dataout_update_r2t(cmd,
 589                                                 be32_to_cpu(hdr->offset),
 590                                                 payload_length) < 0)
 591                                         return DATAOUT_CANNOT_RECOVER;
 592                                 send_r2t = 1;
 593                         }
 594
 595                         if (!conn->sess->sess_ops->DataPDUInOrder) {
 596                                 ret = iscsit_dataout_update_datapduinorder_no(
 597                                                 cmd, be32_to_cpu(hdr->datasn),
 598                                                 (hdr->flags & ISCSI_FLAG_CMD_FINAL));
 599                                 if (ret == DATAOUT_CANNOT_RECOVER)
 600                                         return ret;
 601                         }
 602
 603                         cmd->next_burst_len += payload_length;
 604                         cmd->data_sn++;
 605
 606                         if (send_r2t)
 607                                 cmd->next_burst_len = 0;
 608                 } else {
 609                         seq = cmd->seq_ptr;
 610
 611                         if ((seq->next_burst_len + payload_length) ==
 612                              seq->xfer_len) {
 613                                 if (iscsit_dataout_update_r2t(cmd,
 614                                                 be32_to_cpu(hdr->offset),
 615                                                 payload_length) < 0)
 616                                         return DATAOUT_CANNOT_RECOVER;
 617                                 send_r2t = 1;
 618                         }
 619
 620                         if (!conn->sess->sess_ops->DataPDUInOrder) {
 621                                 ret = iscsit_dataout_update_datapduinorder_no(
 622                                                 cmd, be32_to_cpu(hdr->datasn),
 623                                                 (hdr->flags & ISCSI_FLAG_CMD_FINAL));
 624                                 if (ret == DATAOUT_CANNOT_RECOVER)
 625                                         return ret;
 626                         }
 627
 628                         seq->data_sn++;
 629                         seq->offset += payload_length;
 630                         seq->next_burst_len += payload_length;
 631
 632                         if (send_r2t) {
 633                                 seq->next_burst_len = 0;
 634                                 seq->status = DATAOUT_SEQUENCE_COMPLETE;
 635                         }
 636                 }
 637         }
 638
 639         if (send_r2t && conn->sess->sess_ops->DataSequenceInOrder)
 640                 cmd->data_sn = 0;
 641
 642         cmd->write_data_done += payload_length;
 643
 644         if (cmd->write_data_done == cmd->se_cmd.data_length)
 645                 return DATAOUT_SEND_TO_TRANSPORT;
 646         else if (send_r2t)
 647                 return DATAOUT_SEND_R2T;
 648         else
 649                 return DATAOUT_NORMAL;
 650 }
 651
 652 static int iscsit_dataout_post_crc_failed(
 653         struct iscsi_cmd *cmd,
 654         unsigned char *buf)
 655 {
 656         struct iscsi_conn *conn = cmd->conn;
 657         struct iscsi_pdu *pdu;
 658         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 659         u32 payload_length = ntoh24(hdr->dlength);
 660
 661         if (conn->sess->sess_ops->DataPDUInOrder)
 662                 goto recover;
 663         /*
 664          * The rest of this function is only called when DataPDUInOrder=No.
 665          */
 666         pdu = cmd->pdu_ptr;
 667
 668         switch (pdu->status) {
 669         case ISCSI_PDU_NOT_RECEIVED:
 670                 pdu->status = ISCSI_PDU_CRC_FAILED;
 671                 break;
 672         case ISCSI_PDU_CRC_FAILED:
 673                 break;
 674         case ISCSI_PDU_TIMED_OUT:
 675                 pdu->status = ISCSI_PDU_CRC_FAILED;
 676                 break;
 677         default:
 678                 return DATAOUT_CANNOT_RECOVER;
 679         }
 680
 681 recover:
 682         return iscsit_recover_dataout_sequence(cmd, be32_to_cpu(hdr->offset),
 683                                                 payload_length);
 684 }
 685
 686 /*
 687  *      Called from iscsit_handle_data_out() before DataOUT Payload is received
 688  *      and CRC computed.
 689  */
 690 int iscsit_check_pre_dataout(
 691         struct iscsi_cmd *cmd,
 692         unsigned char *buf)
 693 {
 694         int ret;
 695         struct iscsi_conn *conn = cmd->conn;
 696
 697         ret = iscsit_dataout_within_command_recovery_check(cmd, buf);
 698         if ((ret == DATAOUT_WITHIN_COMMAND_RECOVERY) ||
 699             (ret == DATAOUT_CANNOT_RECOVER))
 700                 return ret;
 701
 702         ret = iscsit_dataout_check_datasn(cmd, buf);
 703         if ((ret == DATAOUT_WITHIN_COMMAND_RECOVERY) ||
 704             (ret == DATAOUT_CANNOT_RECOVER))
 705                 return ret;
 706
 707         if (cmd->unsolicited_data) {
 708                 ret = iscsit_dataout_check_unsolicited_sequence(cmd, buf);
 709                 if ((ret == DATAOUT_WITHIN_COMMAND_RECOVERY) ||
 710                     (ret == DATAOUT_CANNOT_RECOVER))
 711                         return ret;
 712         } else {
 713                 ret = iscsit_dataout_check_sequence(cmd, buf);
 714                 if ((ret == DATAOUT_WITHIN_COMMAND_RECOVERY) ||
 715                     (ret == DATAOUT_CANNOT_RECOVER))
 716                         return ret;
 717         }
 718
 719         return (conn->sess->sess_ops->DataPDUInOrder) ?
 720                 iscsit_dataout_pre_datapduinorder_yes(cmd, buf) :
 721                 iscsit_dataout_pre_datapduinorder_no(cmd, buf);
 722 }
 723
 724 /*
 725  *      Called from iscsit_handle_data_out() after DataOUT Payload is received
 726  *      and CRC computed.
 727  */
 728 int iscsit_check_post_dataout(
 729         struct iscsi_cmd *cmd,
 730         unsigned char *buf,
 731         u8 data_crc_failed)
 732 {
 733         struct iscsi_conn *conn = cmd->conn;
 734
 735         cmd->dataout_timeout_retries = 0;
 736
 737         if (!data_crc_failed)
 738                 return iscsit_dataout_post_crc_passed(cmd, buf);
 739         else {
 740                 if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
 741                         pr_err("Unable to recover from DataOUT CRC"
 742                                 " failure while ERL=0, closing session.\n");
 743                         iscsit_reject_cmd(cmd, ISCSI_REASON_DATA_DIGEST_ERROR,
 744                                           buf);
 745                         return DATAOUT_CANNOT_RECOVER;
 746                 }
 747
 748                 iscsit_reject_cmd(cmd, ISCSI_REASON_DATA_DIGEST_ERROR, buf);
 749                 return iscsit_dataout_post_crc_failed(cmd, buf);
 750         }
 751 }
 752
 753 static void iscsit_handle_time2retain_timeout(unsigned long data)
 754 {
 755         struct iscsi_session *sess = (struct iscsi_session *) data;
 756         struct iscsi_portal_group *tpg = sess->tpg;
 757         struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
 758
 759         spin_lock_bh(&se_tpg->session_lock);
 760         if (sess->time2retain_timer_flags & ISCSI_TF_STOP) {
 761                 spin_unlock_bh(&se_tpg->session_lock);
 762                 return;
 763         }
 764         if (atomic_read(&sess->session_reinstatement)) {
 765                 pr_err("Exiting Time2Retain handler because"
 766                                 " session_reinstatement=1\n");
 767                 spin_unlock_bh(&se_tpg->session_lock);
 768                 return;
 769         }
 770         sess->time2retain_timer_flags |= ISCSI_TF_EXPIRED;
 771
 772         pr_err("Time2Retain timer expired for SID: %u, cleaning up"
 773                         " iSCSI session.\n", sess->sid);
 774         {
 775         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 776
 777         if (tiqn) {
 778                 spin_lock(&tiqn->sess_err_stats.lock);
 779                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 780                         (void *)sess->sess_ops->InitiatorName);
 781                 tiqn->sess_err_stats.last_sess_failure_type =
 782                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 783                 tiqn->sess_err_stats.cxn_timeout_errors++;
 784                 atomic_long_inc(&sess->conn_timeout_errors);
 785                 spin_unlock(&tiqn->sess_err_stats.lock);
 786         }
 787         }
 788
 789         spin_unlock_bh(&se_tpg->session_lock);
 790         target_put_session(sess->se_sess);
 791 }
 792
 793 void iscsit_start_time2retain_handler(struct iscsi_session *sess)
 794 {
 795         int tpg_active;
 796         /*
 797          * Only start Time2Retain timer when the associated TPG is still in
 798          * an ACTIVE (eg: not disabled or shutdown) state.
 799          */
 800         spin_lock(&sess->tpg->tpg_state_lock);
 801         tpg_active = (sess->tpg->tpg_state == TPG_STATE_ACTIVE);
 802         spin_unlock(&sess->tpg->tpg_state_lock);
 803
 804         if (!tpg_active)
 805                 return;
 806
 807         if (sess->time2retain_timer_flags & ISCSI_TF_RUNNING)
 808                 return;
 809
 810         pr_debug("Starting Time2Retain timer for %u seconds on"
 811                 " SID: %u\n", sess->sess_ops->DefaultTime2Retain, sess->sid);
 812
 813         init_timer(&sess->time2retain_timer);
 814         sess->time2retain_timer.expires =
 815                 (get_jiffies_64() + sess->sess_ops->DefaultTime2Retain * HZ);
 816         sess->time2retain_timer.data = (unsigned long)sess;
 817         sess->time2retain_timer.function = iscsit_handle_time2retain_timeout;
 818         sess->time2retain_timer_flags &= ~ISCSI_TF_STOP;
 819         sess->time2retain_timer_flags |= ISCSI_TF_RUNNING;
 820         add_timer(&sess->time2retain_timer);
 821 }
 822
 823 /*
 824  *      Called with spin_lock_bh(&struct se_portal_group->session_lock) held
 825  */
 826 int iscsit_stop_time2retain_timer(struct iscsi_session *sess)
 827 {
 828         struct iscsi_portal_group *tpg = sess->tpg;
 829         struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
 830
 831         if (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)
 832                 return -1;
 833
 834         if (!(sess->time2retain_timer_flags & ISCSI_TF_RUNNING))
 835                 return 0;
 836
 837         sess->time2retain_timer_flags |= ISCSI_TF_STOP;
 838         spin_unlock(&se_tpg->session_lock);
 839
 840         del_timer_sync(&sess->time2retain_timer);
 841
 842         spin_lock(&se_tpg->session_lock);
 843         sess->time2retain_timer_flags &= ~ISCSI_TF_RUNNING;
 844         pr_debug("Stopped Time2Retain Timer for SID: %u\n",
 845                         sess->sid);
 846         return 0;
 847 }
 848
 849 void iscsit_connection_reinstatement_rcfr(struct iscsi_conn *conn)
 850 {
 851         spin_lock_bh(&conn->state_lock);
 852         if (atomic_read(&conn->connection_exit)) {
 853                 spin_unlock_bh(&conn->state_lock);
 854                 goto sleep;
 855         }
 856
 857         if (atomic_read(&conn->transport_failed)) {
 858                 spin_unlock_bh(&conn->state_lock);
 859                 goto sleep;
 860         }
 861         spin_unlock_bh(&conn->state_lock);
 862
 863         iscsi_thread_set_force_reinstatement(conn);
 864
 865 sleep:
 866         wait_for_completion(&conn->conn_wait_rcfr_comp);
 867         complete(&conn->conn_post_wait_comp);
 868 }
 869
 870 void iscsit_cause_connection_reinstatement(struct iscsi_conn *conn, int sleep)
 871 {
 872         spin_lock_bh(&conn->state_lock);
 873         if (atomic_read(&conn->connection_exit)) {
 874                 spin_unlock_bh(&conn->state_lock);
 875                 return;
 876         }
 877
 878         if (atomic_read(&conn->transport_failed)) {
 879                 spin_unlock_bh(&conn->state_lock);
 880                 return;
 881         }
 882
 883         if (atomic_read(&conn->connection_reinstatement)) {
 884                 spin_unlock_bh(&conn->state_lock);
 885                 return;
 886         }
 887
 888         if (iscsi_thread_set_force_reinstatement(conn) < 0) {
 889                 spin_unlock_bh(&conn->state_lock);
 890                 return;
 891         }
 892
 893         atomic_set(&conn->connection_reinstatement, 1);
 894         if (!sleep) {
 895                 spin_unlock_bh(&conn->state_lock);
 896                 return;
 897         }
 898
 899         atomic_set(&conn->sleep_on_conn_wait_comp, 1);
 900         spin_unlock_bh(&conn->state_lock);
 901
 902         wait_for_completion(&conn->conn_wait_comp);
 903         complete(&conn->conn_post_wait_comp);
 904 }
 905 EXPORT_SYMBOL(iscsit_cause_connection_reinstatement);
 906
 907 void iscsit_fall_back_to_erl0(struct iscsi_session *sess)
 908 {
 909         pr_debug("Falling back to ErrorRecoveryLevel=0 for SID:"
 910                         " %u\n", sess->sid);
 911
 912         atomic_set(&sess->session_fall_back_to_erl0, 1);
 913 }
 914
 915 static void iscsit_handle_connection_cleanup(struct iscsi_conn *conn)
 916 {
 917         struct iscsi_session *sess = conn->sess;
 918
 919         if ((sess->sess_ops->ErrorRecoveryLevel == 2) &&
 920             !atomic_read(&sess->session_reinstatement) &&
 921             !atomic_read(&sess->session_fall_back_to_erl0))
 922                 iscsit_connection_recovery_transport_reset(conn);
 923         else {
 924                 pr_debug("Performing cleanup for failed iSCSI"
 925                         " Connection ID: %hu from %s\n", conn->cid,
 926                         sess->sess_ops->InitiatorName);
 927                 iscsit_close_connection(conn);
 928         }
 929 }
 930
 931 void iscsit_take_action_for_connection_exit(struct iscsi_conn *conn)
 932 {
 933         spin_lock_bh(&conn->state_lock);
 934         if (atomic_read(&conn->connection_exit)) {
 935                 spin_unlock_bh(&conn->state_lock);
 936                 return;
 937         }
 938         atomic_set(&conn->connection_exit, 1);
 939
 940         if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT) {
 941                 spin_unlock_bh(&conn->state_lock);
 942                 iscsit_close_connection(conn);
 943                 return;
 944         }
 945
 946         if (conn->conn_state == TARG_CONN_STATE_CLEANUP_WAIT) {
 947                 spin_unlock_bh(&conn->state_lock);
 948                 return;
 949         }
 950
 951         pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
 952         conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
 953         spin_unlock_bh(&conn->state_lock);
 954
 955         iscsit_handle_connection_cleanup(conn);
 956 }
 957
 958 /*
 959  *      This is the simple function that makes the magic of
 960  *      sync and steering happen in the follow paradoxical order:
 961  *
 962  *      0) Receive conn->of_marker (bytes left until next OFMarker)
 963  *         bytes into an offload buffer.  When we pass the exact number
 964  *         of bytes in conn->of_marker, iscsit_dump_data_payload() and hence
 965  *         rx_data() will automatically receive the identical u32 marker
 966  *         values and store it in conn->of_marker_offset;
 967  *      1) Now conn->of_marker_offset will contain the offset to the start
 968  *         of the next iSCSI PDU.  Dump these remaining bytes into another
 969  *         offload buffer.
 970  *      2) We are done!
 971  *         Next byte in the TCP stream will contain the next iSCSI PDU!
 972  *         Cool Huh?!
 973  */
 974 int iscsit_recover_from_unknown_opcode(struct iscsi_conn *conn)
 975 {
 976         /*
 977          * Make sure the remaining bytes to next maker is a sane value.
 978          */
 979         if (conn->of_marker > (conn->conn_ops->OFMarkInt * 4)) {
 980                 pr_err("Remaining bytes to OFMarker: %u exceeds"
 981                         " OFMarkInt bytes: %u.\n", conn->of_marker,
 982                                 conn->conn_ops->OFMarkInt * 4);
 983                 return -1;
 984         }
 985
 986         pr_debug("Advancing %u bytes in TCP stream to get to the"
 987                         " next OFMarker.\n", conn->of_marker);
 988
 989         if (iscsit_dump_data_payload(conn, conn->of_marker, 0) < 0)
 990                 return -1;
 991
 992         /*
 993          * Make sure the offset marker we retrived is a valid value.
 994          */
 995         if (conn->of_marker_offset > (ISCSI_HDR_LEN + (ISCSI_CRC_LEN * 2) +
 996             conn->conn_ops->MaxRecvDataSegmentLength)) {
 997                 pr_err("OfMarker offset value: %u exceeds limit.\n",
 998                         conn->of_marker_offset);
 999                 return -1;
1000         }
1001
1002         pr_debug("Discarding %u bytes of TCP stream to get to the"
1003                         " next iSCSI Opcode.\n", conn->of_marker_offset);
1004
1005         if (iscsit_dump_data_payload(conn, conn->of_marker_offset, 0) < 0)
1006                 return -1;
1007
1008         return 0;
1009 }