drivers/target/iscsi/iscsi_target_datain_values.c

   1 /*******************************************************************************
   2  * This file contains the iSCSI Target DataIN value generation functions.
   3  *
   4  * (c) Copyright 2007-2013 Datera, Inc.
   5  *
   6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  ******************************************************************************/
  18
  19 #include <linux/slab.h>
  20 #include <scsi/iscsi_proto.h>
  21 #include <target/iscsi/iscsi_target_core.h>
  22 #include "iscsi_target_seq_pdu_list.h"
  23 #include "iscsi_target_erl1.h"
  24 #include "iscsi_target_util.h"
  25 #include "iscsi_target.h"
  26 #include "iscsi_target_datain_values.h"
  27
  28 struct iscsi_datain_req *iscsit_allocate_datain_req(void)
  29 {
  30         struct iscsi_datain_req *dr;
  31
  32         dr = kmem_cache_zalloc(lio_dr_cache, GFP_ATOMIC);
  33         if (!dr) {
  34                 pr_err("Unable to allocate memory for"
  35                                 " struct iscsi_datain_req\n");
  36                 return NULL;
  37         }
  38         INIT_LIST_HEAD(&dr->cmd_datain_node);
  39
  40         return dr;
  41 }
  42
  43 void iscsit_attach_datain_req(struct iscsi_cmd *cmd, struct iscsi_datain_req *dr)
  44 {
  45         spin_lock(&cmd->datain_lock);
  46         list_add_tail(&dr->cmd_datain_node, &cmd->datain_list);
  47         spin_unlock(&cmd->datain_lock);
  48 }
  49
  50 void iscsit_free_datain_req(struct iscsi_cmd *cmd, struct iscsi_datain_req *dr)
  51 {
  52         spin_lock(&cmd->datain_lock);
  53         list_del(&dr->cmd_datain_node);
  54         spin_unlock(&cmd->datain_lock);
  55
  56         kmem_cache_free(lio_dr_cache, dr);
  57 }
  58
  59 void iscsit_free_all_datain_reqs(struct iscsi_cmd *cmd)
  60 {
  61         struct iscsi_datain_req *dr, *dr_tmp;
  62
  63         spin_lock(&cmd->datain_lock);
  64         list_for_each_entry_safe(dr, dr_tmp, &cmd->datain_list, cmd_datain_node) {
  65                 list_del(&dr->cmd_datain_node);
  66                 kmem_cache_free(lio_dr_cache, dr);
  67         }
  68         spin_unlock(&cmd->datain_lock);
  69 }
  70
  71 struct iscsi_datain_req *iscsit_get_datain_req(struct iscsi_cmd *cmd)
  72 {
  73         if (list_empty(&cmd->datain_list)) {
  74                 pr_err("cmd->datain_list is empty for ITT:"
  75                         " 0x%08x\n", cmd->init_task_tag);
  76                 return NULL;
  77         }
  78
  79         return list_first_entry(&cmd->datain_list, struct iscsi_datain_req,
  80                                 cmd_datain_node);
  81 }
  82
  83 /*
  84  *      For Normal and Recovery DataSequenceInOrder=Yes and DataPDUInOrder=Yes.
  85  */
  86 static struct iscsi_datain_req *iscsit_set_datain_values_yes_and_yes(
  87         struct iscsi_cmd *cmd,
  88         struct iscsi_datain *datain)
  89 {
  90         u32 next_burst_len, read_data_done, read_data_left;
  91         struct iscsi_conn *conn = cmd->conn;
  92         struct iscsi_datain_req *dr;
  93
  94         dr = iscsit_get_datain_req(cmd);
  95         if (!dr)
  96                 return NULL;
  97
  98         if (dr->recovery && dr->generate_recovery_values) {
  99                 if (iscsit_create_recovery_datain_values_datasequenceinorder_yes(
 100                                         cmd, dr) < 0)
 101                         return NULL;
 102
 103                 dr->generate_recovery_values = 0;
 104         }
 105
 106         next_burst_len = (!dr->recovery) ?
 107                         cmd->next_burst_len : dr->next_burst_len;
 108         read_data_done = (!dr->recovery) ?
 109                         cmd->read_data_done : dr->read_data_done;
 110
 111         read_data_left = (cmd->se_cmd.data_length - read_data_done);
 112         if (!read_data_left) {
 113                 pr_err("ITT: 0x%08x read_data_left is zero!\n",
 114                                 cmd->init_task_tag);
 115                 return NULL;
 116         }
 117
 118         if ((read_data_left <= conn->conn_ops->MaxRecvDataSegmentLength) &&
 119             (read_data_left <= (conn->sess->sess_ops->MaxBurstLength -
 120              next_burst_len))) {
 121                 datain->length = read_data_left;
 122
 123                 datain->flags |= (ISCSI_FLAG_CMD_FINAL | ISCSI_FLAG_DATA_STATUS);
 124                 if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 125                         datain->flags |= ISCSI_FLAG_DATA_ACK;
 126         } else {
 127                 if ((next_burst_len +
 128                      conn->conn_ops->MaxRecvDataSegmentLength) <
 129                      conn->sess->sess_ops->MaxBurstLength) {
 130                         datain->length =
 131                                 conn->conn_ops->MaxRecvDataSegmentLength;
 132                         next_burst_len += datain->length;
 133                 } else {
 134                         datain->length = (conn->sess->sess_ops->MaxBurstLength -
 135                                           next_burst_len);
 136                         next_burst_len = 0;
 137
 138                         datain->flags |= ISCSI_FLAG_CMD_FINAL;
 139                         if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 140                                 datain->flags |= ISCSI_FLAG_DATA_ACK;
 141                 }
 142         }
 143
 144         datain->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
 145         datain->offset = read_data_done;
 146
 147         if (!dr->recovery) {
 148                 cmd->next_burst_len = next_burst_len;
 149                 cmd->read_data_done += datain->length;
 150         } else {
 151                 dr->next_burst_len = next_burst_len;
 152                 dr->read_data_done += datain->length;
 153         }
 154
 155         if (!dr->recovery) {
 156                 if (datain->flags & ISCSI_FLAG_DATA_STATUS)
 157                         dr->dr_complete = DATAIN_COMPLETE_NORMAL;
 158
 159                 return dr;
 160         }
 161
 162         if (!dr->runlength) {
 163                 if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
 164                         dr->dr_complete =
 165                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 166                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 167                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 168                 }
 169         } else {
 170                 if ((dr->begrun + dr->runlength) == dr->data_sn) {
 171                         dr->dr_complete =
 172                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 173                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 174                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 175                 }
 176         }
 177
 178         return dr;
 179 }
 180
 181 /*
 182  *      For Normal and Recovery DataSequenceInOrder=No and DataPDUInOrder=Yes.
 183  */
 184 static struct iscsi_datain_req *iscsit_set_datain_values_no_and_yes(
 185         struct iscsi_cmd *cmd,
 186         struct iscsi_datain *datain)
 187 {
 188         u32 offset, read_data_done, read_data_left, seq_send_order;
 189         struct iscsi_conn *conn = cmd->conn;
 190         struct iscsi_datain_req *dr;
 191         struct iscsi_seq *seq;
 192
 193         dr = iscsit_get_datain_req(cmd);
 194         if (!dr)
 195                 return NULL;
 196
 197         if (dr->recovery && dr->generate_recovery_values) {
 198                 if (iscsit_create_recovery_datain_values_datasequenceinorder_no(
 199                                         cmd, dr) < 0)
 200                         return NULL;
 201
 202                 dr->generate_recovery_values = 0;
 203         }
 204
 205         read_data_done = (!dr->recovery) ?
 206                         cmd->read_data_done : dr->read_data_done;
 207         seq_send_order = (!dr->recovery) ?
 208                         cmd->seq_send_order : dr->seq_send_order;
 209
 210         read_data_left = (cmd->se_cmd.data_length - read_data_done);
 211         if (!read_data_left) {
 212                 pr_err("ITT: 0x%08x read_data_left is zero!\n",
 213                                 cmd->init_task_tag);
 214                 return NULL;
 215         }
 216
 217         seq = iscsit_get_seq_holder_for_datain(cmd, seq_send_order);
 218         if (!seq)
 219                 return NULL;
 220
 221         seq->sent = 1;
 222
 223         if (!dr->recovery && !seq->next_burst_len)
 224                 seq->first_datasn = cmd->data_sn;
 225
 226         offset = (seq->offset + seq->next_burst_len);
 227
 228         if ((offset + conn->conn_ops->MaxRecvDataSegmentLength) >=
 229              cmd->se_cmd.data_length) {
 230                 datain->length = (cmd->se_cmd.data_length - offset);
 231                 datain->offset = offset;
 232
 233                 datain->flags |= ISCSI_FLAG_CMD_FINAL;
 234                 if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 235                         datain->flags |= ISCSI_FLAG_DATA_ACK;
 236
 237                 seq->next_burst_len = 0;
 238                 seq_send_order++;
 239         } else {
 240                 if ((seq->next_burst_len +
 241                      conn->conn_ops->MaxRecvDataSegmentLength) <
 242                      conn->sess->sess_ops->MaxBurstLength) {
 243                         datain->length =
 244                                 conn->conn_ops->MaxRecvDataSegmentLength;
 245                         datain->offset = (seq->offset + seq->next_burst_len);
 246
 247                         seq->next_burst_len += datain->length;
 248                 } else {
 249                         datain->length = (conn->sess->sess_ops->MaxBurstLength -
 250                                           seq->next_burst_len);
 251                         datain->offset = (seq->offset + seq->next_burst_len);
 252
 253                         datain->flags |= ISCSI_FLAG_CMD_FINAL;
 254                         if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 255                                 datain->flags |= ISCSI_FLAG_DATA_ACK;
 256
 257                         seq->next_burst_len = 0;
 258                         seq_send_order++;
 259                 }
 260         }
 261
 262         if ((read_data_done + datain->length) == cmd->se_cmd.data_length)
 263                 datain->flags |= ISCSI_FLAG_DATA_STATUS;
 264
 265         datain->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
 266         if (!dr->recovery) {
 267                 cmd->seq_send_order = seq_send_order;
 268                 cmd->read_data_done += datain->length;
 269         } else {
 270                 dr->seq_send_order = seq_send_order;
 271                 dr->read_data_done += datain->length;
 272         }
 273
 274         if (!dr->recovery) {
 275                 if (datain->flags & ISCSI_FLAG_CMD_FINAL)
 276                         seq->last_datasn = datain->data_sn;
 277                 if (datain->flags & ISCSI_FLAG_DATA_STATUS)
 278                         dr->dr_complete = DATAIN_COMPLETE_NORMAL;
 279
 280                 return dr;
 281         }
 282
 283         if (!dr->runlength) {
 284                 if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
 285                         dr->dr_complete =
 286                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 287                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 288                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 289                 }
 290         } else {
 291                 if ((dr->begrun + dr->runlength) == dr->data_sn) {
 292                         dr->dr_complete =
 293                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 294                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 295                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 296                 }
 297         }
 298
 299         return dr;
 300 }
 301
 302 /*
 303  *      For Normal and Recovery DataSequenceInOrder=Yes and DataPDUInOrder=No.
 304  */
 305 static struct iscsi_datain_req *iscsit_set_datain_values_yes_and_no(
 306         struct iscsi_cmd *cmd,
 307         struct iscsi_datain *datain)
 308 {
 309         u32 next_burst_len, read_data_done, read_data_left;
 310         struct iscsi_conn *conn = cmd->conn;
 311         struct iscsi_datain_req *dr;
 312         struct iscsi_pdu *pdu;
 313
 314         dr = iscsit_get_datain_req(cmd);
 315         if (!dr)
 316                 return NULL;
 317
 318         if (dr->recovery && dr->generate_recovery_values) {
 319                 if (iscsit_create_recovery_datain_values_datasequenceinorder_yes(
 320                                         cmd, dr) < 0)
 321                         return NULL;
 322
 323                 dr->generate_recovery_values = 0;
 324         }
 325
 326         next_burst_len = (!dr->recovery) ?
 327                         cmd->next_burst_len : dr->next_burst_len;
 328         read_data_done = (!dr->recovery) ?
 329                         cmd->read_data_done : dr->read_data_done;
 330
 331         read_data_left = (cmd->se_cmd.data_length - read_data_done);
 332         if (!read_data_left) {
 333                 pr_err("ITT: 0x%08x read_data_left is zero!\n",
 334                                 cmd->init_task_tag);
 335                 return dr;
 336         }
 337
 338         pdu = iscsit_get_pdu_holder_for_seq(cmd, NULL);
 339         if (!pdu)
 340                 return dr;
 341
 342         if ((read_data_done + pdu->length) == cmd->se_cmd.data_length) {
 343                 pdu->flags |= (ISCSI_FLAG_CMD_FINAL | ISCSI_FLAG_DATA_STATUS);
 344                 if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 345                         pdu->flags |= ISCSI_FLAG_DATA_ACK;
 346
 347                 next_burst_len = 0;
 348         } else {
 349                 if ((next_burst_len + conn->conn_ops->MaxRecvDataSegmentLength) <
 350                      conn->sess->sess_ops->MaxBurstLength)
 351                         next_burst_len += pdu->length;
 352                 else {
 353                         pdu->flags |= ISCSI_FLAG_CMD_FINAL;
 354                         if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 355                                 pdu->flags |= ISCSI_FLAG_DATA_ACK;
 356
 357                         next_burst_len = 0;
 358                 }
 359         }
 360
 361         pdu->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
 362         if (!dr->recovery) {
 363                 cmd->next_burst_len = next_burst_len;
 364                 cmd->read_data_done += pdu->length;
 365         } else {
 366                 dr->next_burst_len = next_burst_len;
 367                 dr->read_data_done += pdu->length;
 368         }
 369
 370         datain->flags = pdu->flags;
 371         datain->length = pdu->length;
 372         datain->offset = pdu->offset;
 373         datain->data_sn = pdu->data_sn;
 374
 375         if (!dr->recovery) {
 376                 if (datain->flags & ISCSI_FLAG_DATA_STATUS)
 377                         dr->dr_complete = DATAIN_COMPLETE_NORMAL;
 378
 379                 return dr;
 380         }
 381
 382         if (!dr->runlength) {
 383                 if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
 384                         dr->dr_complete =
 385                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 386                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 387                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 388                 }
 389         } else {
 390                 if ((dr->begrun + dr->runlength) == dr->data_sn) {
 391                         dr->dr_complete =
 392                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 393                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 394                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 395                 }
 396         }
 397
 398         return dr;
 399 }
 400
 401 /*
 402  *      For Normal and Recovery DataSequenceInOrder=No and DataPDUInOrder=No.
 403  */
 404 static struct iscsi_datain_req *iscsit_set_datain_values_no_and_no(
 405         struct iscsi_cmd *cmd,
 406         struct iscsi_datain *datain)
 407 {
 408         u32 read_data_done, read_data_left, seq_send_order;
 409         struct iscsi_conn *conn = cmd->conn;
 410         struct iscsi_datain_req *dr;
 411         struct iscsi_pdu *pdu;
 412         struct iscsi_seq *seq = NULL;
 413
 414         dr = iscsit_get_datain_req(cmd);
 415         if (!dr)
 416                 return NULL;
 417
 418         if (dr->recovery && dr->generate_recovery_values) {
 419                 if (iscsit_create_recovery_datain_values_datasequenceinorder_no(
 420                                         cmd, dr) < 0)
 421                         return NULL;
 422
 423                 dr->generate_recovery_values = 0;
 424         }
 425
 426         read_data_done = (!dr->recovery) ?
 427                         cmd->read_data_done : dr->read_data_done;
 428         seq_send_order = (!dr->recovery) ?
 429                         cmd->seq_send_order : dr->seq_send_order;
 430
 431         read_data_left = (cmd->se_cmd.data_length - read_data_done);
 432         if (!read_data_left) {
 433                 pr_err("ITT: 0x%08x read_data_left is zero!\n",
 434                                 cmd->init_task_tag);
 435                 return NULL;
 436         }
 437
 438         seq = iscsit_get_seq_holder_for_datain(cmd, seq_send_order);
 439         if (!seq)
 440                 return NULL;
 441
 442         seq->sent = 1;
 443
 444         if (!dr->recovery && !seq->next_burst_len)
 445                 seq->first_datasn = cmd->data_sn;
 446
 447         pdu = iscsit_get_pdu_holder_for_seq(cmd, seq);
 448         if (!pdu)
 449                 return NULL;
 450
 451         if (seq->pdu_send_order == seq->pdu_count) {
 452                 pdu->flags |= ISCSI_FLAG_CMD_FINAL;
 453                 if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 454                         pdu->flags |= ISCSI_FLAG_DATA_ACK;
 455
 456                 seq->next_burst_len = 0;
 457                 seq_send_order++;
 458         } else
 459                 seq->next_burst_len += pdu->length;
 460
 461         if ((read_data_done + pdu->length) == cmd->se_cmd.data_length)
 462                 pdu->flags |= ISCSI_FLAG_DATA_STATUS;
 463
 464         pdu->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
 465         if (!dr->recovery) {
 466                 cmd->seq_send_order = seq_send_order;
 467                 cmd->read_data_done += pdu->length;
 468         } else {
 469                 dr->seq_send_order = seq_send_order;
 470                 dr->read_data_done += pdu->length;
 471         }
 472
 473         datain->flags = pdu->flags;
 474         datain->length = pdu->length;
 475         datain->offset = pdu->offset;
 476         datain->data_sn = pdu->data_sn;
 477
 478         if (!dr->recovery) {
 479                 if (datain->flags & ISCSI_FLAG_CMD_FINAL)
 480                         seq->last_datasn = datain->data_sn;
 481                 if (datain->flags & ISCSI_FLAG_DATA_STATUS)
 482                         dr->dr_complete = DATAIN_COMPLETE_NORMAL;
 483
 484                 return dr;
 485         }
 486
 487         if (!dr->runlength) {
 488                 if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
 489                         dr->dr_complete =
 490                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 491                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 492                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 493                 }
 494         } else {
 495                 if ((dr->begrun + dr->runlength) == dr->data_sn) {
 496                         dr->dr_complete =
 497                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 498                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 499                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 500                 }
 501         }
 502
 503         return dr;
 504 }
 505
 506 struct iscsi_datain_req *iscsit_get_datain_values(
 507         struct iscsi_cmd *cmd,
 508         struct iscsi_datain *datain)
 509 {
 510         struct iscsi_conn *conn = cmd->conn;
 511
 512         if (conn->sess->sess_ops->DataSequenceInOrder &&
 513             conn->sess->sess_ops->DataPDUInOrder)
 514                 return iscsit_set_datain_values_yes_and_yes(cmd, datain);
 515         else if (!conn->sess->sess_ops->DataSequenceInOrder &&
 516                   conn->sess->sess_ops->DataPDUInOrder)
 517                 return iscsit_set_datain_values_no_and_yes(cmd, datain);
 518         else if (conn->sess->sess_ops->DataSequenceInOrder &&
 519                  !conn->sess->sess_ops->DataPDUInOrder)
 520                 return iscsit_set_datain_values_yes_and_no(cmd, datain);
 521         else if (!conn->sess->sess_ops->DataSequenceInOrder &&
 522                    !conn->sess->sess_ops->DataPDUInOrder)
 523                 return iscsit_set_datain_values_no_and_no(cmd, datain);
 524
 525         return NULL;
 526 }
 527 EXPORT_SYMBOL(iscsit_get_datain_values);