drivers/target/iscsi/iscsi_target_datain_values.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*******************************************************************************
   3  * This file contains the iSCSI Target DataIN value generation functions.
   4  *
   5  * (c) Copyright 2007-2013 Datera, Inc.
   6  *
   7  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   8  *
   9  ******************************************************************************/
  10
  11 #include <linux/slab.h>
  12 #include <scsi/iscsi_proto.h>
  13 #include <target/iscsi/iscsi_target_core.h>
  14 #include "iscsi_target_seq_pdu_list.h"
  15 #include "iscsi_target_erl1.h"
  16 #include "iscsi_target_util.h"
  17 #include "iscsi_target.h"
  18 #include "iscsi_target_datain_values.h"
  19
  20 struct iscsi_datain_req *iscsit_allocate_datain_req(void)
  21 {
  22         struct iscsi_datain_req *dr;
  23
  24         dr = kmem_cache_zalloc(lio_dr_cache, GFP_ATOMIC);
  25         if (!dr) {
  26                 pr_err("Unable to allocate memory for"
  27                                 " struct iscsi_datain_req\n");
  28                 return NULL;
  29         }
  30         INIT_LIST_HEAD(&dr->cmd_datain_node);
  31
  32         return dr;
  33 }
  34
  35 void iscsit_attach_datain_req(struct iscsi_cmd *cmd, struct iscsi_datain_req *dr)
  36 {
  37         spin_lock(&cmd->datain_lock);
  38         list_add_tail(&dr->cmd_datain_node, &cmd->datain_list);
  39         spin_unlock(&cmd->datain_lock);
  40 }
  41
  42 void iscsit_free_datain_req(struct iscsi_cmd *cmd, struct iscsi_datain_req *dr)
  43 {
  44         spin_lock(&cmd->datain_lock);
  45         list_del(&dr->cmd_datain_node);
  46         spin_unlock(&cmd->datain_lock);
  47
  48         kmem_cache_free(lio_dr_cache, dr);
  49 }
  50
  51 void iscsit_free_all_datain_reqs(struct iscsi_cmd *cmd)
  52 {
  53         struct iscsi_datain_req *dr, *dr_tmp;
  54
  55         spin_lock(&cmd->datain_lock);
  56         list_for_each_entry_safe(dr, dr_tmp, &cmd->datain_list, cmd_datain_node) {
  57                 list_del(&dr->cmd_datain_node);
  58                 kmem_cache_free(lio_dr_cache, dr);
  59         }
  60         spin_unlock(&cmd->datain_lock);
  61 }
  62
  63 struct iscsi_datain_req *iscsit_get_datain_req(struct iscsi_cmd *cmd)
  64 {
  65         if (list_empty(&cmd->datain_list)) {
  66                 pr_err("cmd->datain_list is empty for ITT:"
  67                         " 0x%08x\n", cmd->init_task_tag);
  68                 return NULL;
  69         }
  70
  71         return list_first_entry(&cmd->datain_list, struct iscsi_datain_req,
  72                                 cmd_datain_node);
  73 }
  74
  75 /*
  76  *      For Normal and Recovery DataSequenceInOrder=Yes and DataPDUInOrder=Yes.
  77  */
  78 static struct iscsi_datain_req *iscsit_set_datain_values_yes_and_yes(
  79         struct iscsi_cmd *cmd,
  80         struct iscsi_datain *datain)
  81 {
  82         u32 next_burst_len, read_data_done, read_data_left;
  83         struct iscsi_conn *conn = cmd->conn;
  84         struct iscsi_datain_req *dr;
  85
  86         dr = iscsit_get_datain_req(cmd);
  87         if (!dr)
  88                 return NULL;
  89
  90         if (dr->recovery && dr->generate_recovery_values) {
  91                 if (iscsit_create_recovery_datain_values_datasequenceinorder_yes(
  92                                         cmd, dr) < 0)
  93                         return NULL;
  94
  95                 dr->generate_recovery_values = 0;
  96         }
  97
  98         next_burst_len = (!dr->recovery) ?
  99                         cmd->next_burst_len : dr->next_burst_len;
 100         read_data_done = (!dr->recovery) ?
 101                         cmd->read_data_done : dr->read_data_done;
 102
 103         read_data_left = (cmd->se_cmd.data_length - read_data_done);
 104         if (!read_data_left) {
 105                 pr_err("ITT: 0x%08x read_data_left is zero!\n",
 106                                 cmd->init_task_tag);
 107                 return NULL;
 108         }
 109
 110         if ((read_data_left <= conn->conn_ops->MaxRecvDataSegmentLength) &&
 111             (read_data_left <= (conn->sess->sess_ops->MaxBurstLength -
 112              next_burst_len))) {
 113                 datain->length = read_data_left;
 114
 115                 datain->flags |= (ISCSI_FLAG_CMD_FINAL | ISCSI_FLAG_DATA_STATUS);
 116                 if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 117                         datain->flags |= ISCSI_FLAG_DATA_ACK;
 118         } else {
 119                 if ((next_burst_len +
 120                      conn->conn_ops->MaxRecvDataSegmentLength) <
 121                      conn->sess->sess_ops->MaxBurstLength) {
 122                         datain->length =
 123                                 conn->conn_ops->MaxRecvDataSegmentLength;
 124                         next_burst_len += datain->length;
 125                 } else {
 126                         datain->length = (conn->sess->sess_ops->MaxBurstLength -
 127                                           next_burst_len);
 128                         next_burst_len = 0;
 129
 130                         datain->flags |= ISCSI_FLAG_CMD_FINAL;
 131                         if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 132                                 datain->flags |= ISCSI_FLAG_DATA_ACK;
 133                 }
 134         }
 135
 136         datain->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
 137         datain->offset = read_data_done;
 138
 139         if (!dr->recovery) {
 140                 cmd->next_burst_len = next_burst_len;
 141                 cmd->read_data_done += datain->length;
 142         } else {
 143                 dr->next_burst_len = next_burst_len;
 144                 dr->read_data_done += datain->length;
 145         }
 146
 147         if (!dr->recovery) {
 148                 if (datain->flags & ISCSI_FLAG_DATA_STATUS)
 149                         dr->dr_complete = DATAIN_COMPLETE_NORMAL;
 150
 151                 return dr;
 152         }
 153
 154         if (!dr->runlength) {
 155                 if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
 156                         dr->dr_complete =
 157                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 158                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 159                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 160                 }
 161         } else {
 162                 if ((dr->begrun + dr->runlength) == dr->data_sn) {
 163                         dr->dr_complete =
 164                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 165                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 166                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 167                 }
 168         }
 169
 170         return dr;
 171 }
 172
 173 /*
 174  *      For Normal and Recovery DataSequenceInOrder=No and DataPDUInOrder=Yes.
 175  */
 176 static struct iscsi_datain_req *iscsit_set_datain_values_no_and_yes(
 177         struct iscsi_cmd *cmd,
 178         struct iscsi_datain *datain)
 179 {
 180         u32 offset, read_data_done, read_data_left, seq_send_order;
 181         struct iscsi_conn *conn = cmd->conn;
 182         struct iscsi_datain_req *dr;
 183         struct iscsi_seq *seq;
 184
 185         dr = iscsit_get_datain_req(cmd);
 186         if (!dr)
 187                 return NULL;
 188
 189         if (dr->recovery && dr->generate_recovery_values) {
 190                 if (iscsit_create_recovery_datain_values_datasequenceinorder_no(
 191                                         cmd, dr) < 0)
 192                         return NULL;
 193
 194                 dr->generate_recovery_values = 0;
 195         }
 196
 197         read_data_done = (!dr->recovery) ?
 198                         cmd->read_data_done : dr->read_data_done;
 199         seq_send_order = (!dr->recovery) ?
 200                         cmd->seq_send_order : dr->seq_send_order;
 201
 202         read_data_left = (cmd->se_cmd.data_length - read_data_done);
 203         if (!read_data_left) {
 204                 pr_err("ITT: 0x%08x read_data_left is zero!\n",
 205                                 cmd->init_task_tag);
 206                 return NULL;
 207         }
 208
 209         seq = iscsit_get_seq_holder_for_datain(cmd, seq_send_order);
 210         if (!seq)
 211                 return NULL;
 212
 213         seq->sent = 1;
 214
 215         if (!dr->recovery && !seq->next_burst_len)
 216                 seq->first_datasn = cmd->data_sn;
 217
 218         offset = (seq->offset + seq->next_burst_len);
 219
 220         if ((offset + conn->conn_ops->MaxRecvDataSegmentLength) >=
 221              cmd->se_cmd.data_length) {
 222                 datain->length = (cmd->se_cmd.data_length - offset);
 223                 datain->offset = offset;
 224
 225                 datain->flags |= ISCSI_FLAG_CMD_FINAL;
 226                 if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 227                         datain->flags |= ISCSI_FLAG_DATA_ACK;
 228
 229                 seq->next_burst_len = 0;
 230                 seq_send_order++;
 231         } else {
 232                 if ((seq->next_burst_len +
 233                      conn->conn_ops->MaxRecvDataSegmentLength) <
 234                      conn->sess->sess_ops->MaxBurstLength) {
 235                         datain->length =
 236                                 conn->conn_ops->MaxRecvDataSegmentLength;
 237                         datain->offset = (seq->offset + seq->next_burst_len);
 238
 239                         seq->next_burst_len += datain->length;
 240                 } else {
 241                         datain->length = (conn->sess->sess_ops->MaxBurstLength -
 242                                           seq->next_burst_len);
 243                         datain->offset = (seq->offset + seq->next_burst_len);
 244
 245                         datain->flags |= ISCSI_FLAG_CMD_FINAL;
 246                         if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 247                                 datain->flags |= ISCSI_FLAG_DATA_ACK;
 248
 249                         seq->next_burst_len = 0;
 250                         seq_send_order++;
 251                 }
 252         }
 253
 254         if ((read_data_done + datain->length) == cmd->se_cmd.data_length)
 255                 datain->flags |= ISCSI_FLAG_DATA_STATUS;
 256
 257         datain->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
 258         if (!dr->recovery) {
 259                 cmd->seq_send_order = seq_send_order;
 260                 cmd->read_data_done += datain->length;
 261         } else {
 262                 dr->seq_send_order = seq_send_order;
 263                 dr->read_data_done += datain->length;
 264         }
 265
 266         if (!dr->recovery) {
 267                 if (datain->flags & ISCSI_FLAG_CMD_FINAL)
 268                         seq->last_datasn = datain->data_sn;
 269                 if (datain->flags & ISCSI_FLAG_DATA_STATUS)
 270                         dr->dr_complete = DATAIN_COMPLETE_NORMAL;
 271
 272                 return dr;
 273         }
 274
 275         if (!dr->runlength) {
 276                 if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
 277                         dr->dr_complete =
 278                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 279                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 280                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 281                 }
 282         } else {
 283                 if ((dr->begrun + dr->runlength) == dr->data_sn) {
 284                         dr->dr_complete =
 285                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 286                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 287                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 288                 }
 289         }
 290
 291         return dr;
 292 }
 293
 294 /*
 295  *      For Normal and Recovery DataSequenceInOrder=Yes and DataPDUInOrder=No.
 296  */
 297 static struct iscsi_datain_req *iscsit_set_datain_values_yes_and_no(
 298         struct iscsi_cmd *cmd,
 299         struct iscsi_datain *datain)
 300 {
 301         u32 next_burst_len, read_data_done, read_data_left;
 302         struct iscsi_conn *conn = cmd->conn;
 303         struct iscsi_datain_req *dr;
 304         struct iscsi_pdu *pdu;
 305
 306         dr = iscsit_get_datain_req(cmd);
 307         if (!dr)
 308                 return NULL;
 309
 310         if (dr->recovery && dr->generate_recovery_values) {
 311                 if (iscsit_create_recovery_datain_values_datasequenceinorder_yes(
 312                                         cmd, dr) < 0)
 313                         return NULL;
 314
 315                 dr->generate_recovery_values = 0;
 316         }
 317
 318         next_burst_len = (!dr->recovery) ?
 319                         cmd->next_burst_len : dr->next_burst_len;
 320         read_data_done = (!dr->recovery) ?
 321                         cmd->read_data_done : dr->read_data_done;
 322
 323         read_data_left = (cmd->se_cmd.data_length - read_data_done);
 324         if (!read_data_left) {
 325                 pr_err("ITT: 0x%08x read_data_left is zero!\n",
 326                                 cmd->init_task_tag);
 327                 return dr;
 328         }
 329
 330         pdu = iscsit_get_pdu_holder_for_seq(cmd, NULL);
 331         if (!pdu)
 332                 return dr;
 333
 334         if ((read_data_done + pdu->length) == cmd->se_cmd.data_length) {
 335                 pdu->flags |= (ISCSI_FLAG_CMD_FINAL | ISCSI_FLAG_DATA_STATUS);
 336                 if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 337                         pdu->flags |= ISCSI_FLAG_DATA_ACK;
 338
 339                 next_burst_len = 0;
 340         } else {
 341                 if ((next_burst_len + conn->conn_ops->MaxRecvDataSegmentLength) <
 342                      conn->sess->sess_ops->MaxBurstLength)
 343                         next_burst_len += pdu->length;
 344                 else {
 345                         pdu->flags |= ISCSI_FLAG_CMD_FINAL;
 346                         if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 347                                 pdu->flags |= ISCSI_FLAG_DATA_ACK;
 348
 349                         next_burst_len = 0;
 350                 }
 351         }
 352
 353         pdu->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
 354         if (!dr->recovery) {
 355                 cmd->next_burst_len = next_burst_len;
 356                 cmd->read_data_done += pdu->length;
 357         } else {
 358                 dr->next_burst_len = next_burst_len;
 359                 dr->read_data_done += pdu->length;
 360         }
 361
 362         datain->flags = pdu->flags;
 363         datain->length = pdu->length;
 364         datain->offset = pdu->offset;
 365         datain->data_sn = pdu->data_sn;
 366
 367         if (!dr->recovery) {
 368                 if (datain->flags & ISCSI_FLAG_DATA_STATUS)
 369                         dr->dr_complete = DATAIN_COMPLETE_NORMAL;
 370
 371                 return dr;
 372         }
 373
 374         if (!dr->runlength) {
 375                 if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
 376                         dr->dr_complete =
 377                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 378                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 379                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 380                 }
 381         } else {
 382                 if ((dr->begrun + dr->runlength) == dr->data_sn) {
 383                         dr->dr_complete =
 384                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 385                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 386                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 387                 }
 388         }
 389
 390         return dr;
 391 }
 392
 393 /*
 394  *      For Normal and Recovery DataSequenceInOrder=No and DataPDUInOrder=No.
 395  */
 396 static struct iscsi_datain_req *iscsit_set_datain_values_no_and_no(
 397         struct iscsi_cmd *cmd,
 398         struct iscsi_datain *datain)
 399 {
 400         u32 read_data_done, read_data_left, seq_send_order;
 401         struct iscsi_conn *conn = cmd->conn;
 402         struct iscsi_datain_req *dr;
 403         struct iscsi_pdu *pdu;
 404         struct iscsi_seq *seq = NULL;
 405
 406         dr = iscsit_get_datain_req(cmd);
 407         if (!dr)
 408                 return NULL;
 409
 410         if (dr->recovery && dr->generate_recovery_values) {
 411                 if (iscsit_create_recovery_datain_values_datasequenceinorder_no(
 412                                         cmd, dr) < 0)
 413                         return NULL;
 414
 415                 dr->generate_recovery_values = 0;
 416         }
 417
 418         read_data_done = (!dr->recovery) ?
 419                         cmd->read_data_done : dr->read_data_done;
 420         seq_send_order = (!dr->recovery) ?
 421                         cmd->seq_send_order : dr->seq_send_order;
 422
 423         read_data_left = (cmd->se_cmd.data_length - read_data_done);
 424         if (!read_data_left) {
 425                 pr_err("ITT: 0x%08x read_data_left is zero!\n",
 426                                 cmd->init_task_tag);
 427                 return NULL;
 428         }
 429
 430         seq = iscsit_get_seq_holder_for_datain(cmd, seq_send_order);
 431         if (!seq)
 432                 return NULL;
 433
 434         seq->sent = 1;
 435
 436         if (!dr->recovery && !seq->next_burst_len)
 437                 seq->first_datasn = cmd->data_sn;
 438
 439         pdu = iscsit_get_pdu_holder_for_seq(cmd, seq);
 440         if (!pdu)
 441                 return NULL;
 442
 443         if (seq->pdu_send_order == seq->pdu_count) {
 444                 pdu->flags |= ISCSI_FLAG_CMD_FINAL;
 445                 if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
 446                         pdu->flags |= ISCSI_FLAG_DATA_ACK;
 447
 448                 seq->next_burst_len = 0;
 449                 seq_send_order++;
 450         } else
 451                 seq->next_burst_len += pdu->length;
 452
 453         if ((read_data_done + pdu->length) == cmd->se_cmd.data_length)
 454                 pdu->flags |= ISCSI_FLAG_DATA_STATUS;
 455
 456         pdu->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
 457         if (!dr->recovery) {
 458                 cmd->seq_send_order = seq_send_order;
 459                 cmd->read_data_done += pdu->length;
 460         } else {
 461                 dr->seq_send_order = seq_send_order;
 462                 dr->read_data_done += pdu->length;
 463         }
 464
 465         datain->flags = pdu->flags;
 466         datain->length = pdu->length;
 467         datain->offset = pdu->offset;
 468         datain->data_sn = pdu->data_sn;
 469
 470         if (!dr->recovery) {
 471                 if (datain->flags & ISCSI_FLAG_CMD_FINAL)
 472                         seq->last_datasn = datain->data_sn;
 473                 if (datain->flags & ISCSI_FLAG_DATA_STATUS)
 474                         dr->dr_complete = DATAIN_COMPLETE_NORMAL;
 475
 476                 return dr;
 477         }
 478
 479         if (!dr->runlength) {
 480                 if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
 481                         dr->dr_complete =
 482                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 483                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 484                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 485                 }
 486         } else {
 487                 if ((dr->begrun + dr->runlength) == dr->data_sn) {
 488                         dr->dr_complete =
 489                             (dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
 490                                 DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
 491                                 DATAIN_COMPLETE_CONNECTION_RECOVERY;
 492                 }
 493         }
 494
 495         return dr;
 496 }
 497
 498 struct iscsi_datain_req *iscsit_get_datain_values(
 499         struct iscsi_cmd *cmd,
 500         struct iscsi_datain *datain)
 501 {
 502         struct iscsi_conn *conn = cmd->conn;
 503
 504         if (conn->sess->sess_ops->DataSequenceInOrder &&
 505             conn->sess->sess_ops->DataPDUInOrder)
 506                 return iscsit_set_datain_values_yes_and_yes(cmd, datain);
 507         else if (!conn->sess->sess_ops->DataSequenceInOrder &&
 508                   conn->sess->sess_ops->DataPDUInOrder)
 509                 return iscsit_set_datain_values_no_and_yes(cmd, datain);
 510         else if (conn->sess->sess_ops->DataSequenceInOrder &&
 511                  !conn->sess->sess_ops->DataPDUInOrder)
 512                 return iscsit_set_datain_values_yes_and_no(cmd, datain);
 513         else if (!conn->sess->sess_ops->DataSequenceInOrder &&
 514                    !conn->sess->sess_ops->DataPDUInOrder)
 515                 return iscsit_set_datain_values_no_and_no(cmd, datain);
 516
 517         return NULL;
 518 }
 519 EXPORT_SYMBOL(iscsit_get_datain_values);