drivers/target/iscsi/iscsi_target_util.c

   1 /*******************************************************************************
   2  * This file contains the iSCSI Target specific utility functions.
   3  *
   4  * \u00a9 Copyright 2007-2011 RisingTide Systems LLC.
   5  *
   6  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   7  *
   8  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  ******************************************************************************/
  20
  21 #include <linux/list.h>
  22 #include <scsi/scsi_tcq.h>
  23 #include <scsi/iscsi_proto.h>
  24 #include <target/target_core_base.h>
  25 #include <target/target_core_fabric.h>
  26 #include <target/target_core_configfs.h>
  27
  28 #include "iscsi_target_core.h"
  29 #include "iscsi_target_parameters.h"
  30 #include "iscsi_target_seq_pdu_list.h"
  31 #include "iscsi_target_datain_values.h"
  32 #include "iscsi_target_erl0.h"
  33 #include "iscsi_target_erl1.h"
  34 #include "iscsi_target_erl2.h"
  35 #include "iscsi_target_tpg.h"
  36 #include "iscsi_target_tq.h"
  37 #include "iscsi_target_util.h"
  38 #include "iscsi_target.h"
  39
  40 #define PRINT_BUFF(buff, len)                                   \
  41 {                                                               \
  42         int zzz;                                                \
  43                                                                 \
  44         pr_debug("%d:\n", __LINE__);                            \
  45         for (zzz = 0; zzz < len; zzz++) {                       \
  46                 if (zzz % 16 == 0) {                            \
  47                         if (zzz)                                \
  48                                 pr_debug("\n");                 \
  49                         pr_debug("%4i: ", zzz);                 \
  50                 }                                               \
  51                 pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  52         }                                                       \
  53         if ((len + 1) % 16)                                     \
  54                 pr_debug("\n");                                 \
  55 }
  56
  57 extern struct list_head g_tiqn_list;
  58 extern spinlock_t tiqn_lock;
  59
  60 /*
  61  *      Called with cmd->r2t_lock held.
  62  */
  63 int iscsit_add_r2t_to_list(
  64         struct iscsi_cmd *cmd,
  65         u32 offset,
  66         u32 xfer_len,
  67         int recovery,
  68         u32 r2t_sn)
  69 {
  70         struct iscsi_r2t *r2t;
  71
  72         r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  73         if (!r2t) {
  74                 pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  75                 return -1;
  76         }
  77         INIT_LIST_HEAD(&r2t->r2t_list);
  78
  79         r2t->recovery_r2t = recovery;
  80         r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  81         r2t->offset = offset;
  82         r2t->xfer_len = xfer_len;
  83         list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  84         spin_unlock_bh(&cmd->r2t_lock);
  85
  86         iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  87
  88         spin_lock_bh(&cmd->r2t_lock);
  89         return 0;
  90 }
  91
  92 struct iscsi_r2t *iscsit_get_r2t_for_eos(
  93         struct iscsi_cmd *cmd,
  94         u32 offset,
  95         u32 length)
  96 {
  97         struct iscsi_r2t *r2t;
  98
  99         spin_lock_bh(&cmd->r2t_lock);
 100         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 101                 if ((r2t->offset <= offset) &&
 102                     (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 103                         spin_unlock_bh(&cmd->r2t_lock);
 104                         return r2t;
 105                 }
 106         }
 107         spin_unlock_bh(&cmd->r2t_lock);
 108
 109         pr_err("Unable to locate R2T for Offset: %u, Length:"
 110                         " %u\n", offset, length);
 111         return NULL;
 112 }
 113
 114 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 115 {
 116         struct iscsi_r2t *r2t;
 117
 118         spin_lock_bh(&cmd->r2t_lock);
 119         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 120                 if (!r2t->sent_r2t) {
 121                         spin_unlock_bh(&cmd->r2t_lock);
 122                         return r2t;
 123                 }
 124         }
 125         spin_unlock_bh(&cmd->r2t_lock);
 126
 127         pr_err("Unable to locate next R2T to send for ITT:"
 128                         " 0x%08x.\n", cmd->init_task_tag);
 129         return NULL;
 130 }
 131
 132 /*
 133  *      Called with cmd->r2t_lock held.
 134  */
 135 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 136 {
 137         list_del(&r2t->r2t_list);
 138         kmem_cache_free(lio_r2t_cache, r2t);
 139 }
 140
 141 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 142 {
 143         struct iscsi_r2t *r2t, *r2t_tmp;
 144
 145         spin_lock_bh(&cmd->r2t_lock);
 146         list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 147                 iscsit_free_r2t(r2t, cmd);
 148         spin_unlock_bh(&cmd->r2t_lock);
 149 }
 150
 151 /*
 152  * May be called from software interrupt (timer) context for allocating
 153  * iSCSI NopINs.
 154  */
 155 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, gfp_t gfp_mask)
 156 {
 157         struct iscsi_cmd *cmd;
 158
 159         cmd = kmem_cache_zalloc(lio_cmd_cache, gfp_mask);
 160         if (!cmd) {
 161                 pr_err("Unable to allocate memory for struct iscsi_cmd.\n");
 162                 return NULL;
 163         }
 164
 165         cmd->conn       = conn;
 166         INIT_LIST_HEAD(&cmd->i_conn_node);
 167         INIT_LIST_HEAD(&cmd->datain_list);
 168         INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 169         init_completion(&cmd->reject_comp);
 170         spin_lock_init(&cmd->datain_lock);
 171         spin_lock_init(&cmd->dataout_timeout_lock);
 172         spin_lock_init(&cmd->istate_lock);
 173         spin_lock_init(&cmd->error_lock);
 174         spin_lock_init(&cmd->r2t_lock);
 175
 176         return cmd;
 177 }
 178
 179 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 180         struct iscsi_cmd *cmd,
 181         u32 seq_send_order)
 182 {
 183         u32 i;
 184
 185         for (i = 0; i < cmd->seq_count; i++)
 186                 if (cmd->seq_list[i].seq_send_order == seq_send_order)
 187                         return &cmd->seq_list[i];
 188
 189         return NULL;
 190 }
 191
 192 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 193 {
 194         u32 i;
 195
 196         if (!cmd->seq_list) {
 197                 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 198                 return NULL;
 199         }
 200
 201         for (i = 0; i < cmd->seq_count; i++) {
 202                 if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 203                         continue;
 204                 if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 205                         cmd->seq_send_order++;
 206                         return &cmd->seq_list[i];
 207                 }
 208         }
 209
 210         return NULL;
 211 }
 212
 213 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 214         struct iscsi_cmd *cmd,
 215         u32 r2t_sn)
 216 {
 217         struct iscsi_r2t *r2t;
 218
 219         spin_lock_bh(&cmd->r2t_lock);
 220         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 221                 if (r2t->r2t_sn == r2t_sn) {
 222                         spin_unlock_bh(&cmd->r2t_lock);
 223                         return r2t;
 224                 }
 225         }
 226         spin_unlock_bh(&cmd->r2t_lock);
 227
 228         return NULL;
 229 }
 230
 231 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 232 {
 233         int ret;
 234
 235         /*
 236          * This is the proper method of checking received CmdSN against
 237          * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 238          * or order CmdSNs due to multiple connection sessions and/or
 239          * CRC failures.
 240          */
 241         if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) {
 242                 pr_err("Received CmdSN: 0x%08x is greater than"
 243                        " MaxCmdSN: 0x%08x, protocol error.\n", cmdsn,
 244                        sess->max_cmd_sn);
 245                 ret = CMDSN_ERROR_CANNOT_RECOVER;
 246
 247         } else if (cmdsn == sess->exp_cmd_sn) {
 248                 sess->exp_cmd_sn++;
 249                 pr_debug("Received CmdSN matches ExpCmdSN,"
 250                       " incremented ExpCmdSN to: 0x%08x\n",
 251                       sess->exp_cmd_sn);
 252                 ret = CMDSN_NORMAL_OPERATION;
 253
 254         } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 255                 pr_debug("Received CmdSN: 0x%08x is greater"
 256                       " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 257                       cmdsn, sess->exp_cmd_sn);
 258                 ret = CMDSN_HIGHER_THAN_EXP;
 259
 260         } else {
 261                 pr_err("Received CmdSN: 0x%08x is less than"
 262                        " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 263                        sess->exp_cmd_sn);
 264                 ret = CMDSN_LOWER_THAN_EXP;
 265         }
 266
 267         return ret;
 268 }
 269
 270 /*
 271  * Commands may be received out of order if MC/S is in use.
 272  * Ensure they are executed in CmdSN order.
 273  */
 274 int iscsit_sequence_cmd(
 275         struct iscsi_conn *conn,
 276         struct iscsi_cmd *cmd,
 277         __be32 cmdsn)
 278 {
 279         int ret;
 280         int cmdsn_ret;
 281
 282         mutex_lock(&conn->sess->cmdsn_mutex);
 283
 284         cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
 285         switch (cmdsn_ret) {
 286         case CMDSN_NORMAL_OPERATION:
 287                 ret = iscsit_execute_cmd(cmd, 0);
 288                 if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 289                         iscsit_execute_ooo_cmdsns(conn->sess);
 290                 break;
 291         case CMDSN_HIGHER_THAN_EXP:
 292                 ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
 293                 break;
 294         case CMDSN_LOWER_THAN_EXP:
 295                 cmd->i_state = ISTATE_REMOVE;
 296                 iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 297                 ret = cmdsn_ret;
 298                 break;
 299         default:
 300                 ret = cmdsn_ret;
 301                 break;
 302         }
 303         mutex_unlock(&conn->sess->cmdsn_mutex);
 304
 305         return ret;
 306 }
 307
 308 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 309 {
 310         struct iscsi_conn *conn = cmd->conn;
 311         struct se_cmd *se_cmd = &cmd->se_cmd;
 312         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 313         u32 payload_length = ntoh24(hdr->dlength);
 314
 315         if (conn->sess->sess_ops->InitialR2T) {
 316                 pr_err("Received unexpected unsolicited data"
 317                         " while InitialR2T=Yes, protocol error.\n");
 318                 transport_send_check_condition_and_sense(se_cmd,
 319                                 TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 320                 return -1;
 321         }
 322
 323         if ((cmd->first_burst_len + payload_length) >
 324              conn->sess->sess_ops->FirstBurstLength) {
 325                 pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 326                         " for this Unsolicited DataOut Burst.\n",
 327                         (cmd->first_burst_len + payload_length),
 328                                 conn->sess->sess_ops->FirstBurstLength);
 329                 transport_send_check_condition_and_sense(se_cmd,
 330                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 331                 return -1;
 332         }
 333
 334         if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 335                 return 0;
 336
 337         if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 338             ((cmd->first_burst_len + payload_length) !=
 339               conn->sess->sess_ops->FirstBurstLength)) {
 340                 pr_err("Unsolicited non-immediate data received %u"
 341                         " does not equal FirstBurstLength: %u, and does"
 342                         " not equal ExpXferLen %u.\n",
 343                         (cmd->first_burst_len + payload_length),
 344                         conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 345                 transport_send_check_condition_and_sense(se_cmd,
 346                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 347                 return -1;
 348         }
 349         return 0;
 350 }
 351
 352 struct iscsi_cmd *iscsit_find_cmd_from_itt(
 353         struct iscsi_conn *conn,
 354         itt_t init_task_tag)
 355 {
 356         struct iscsi_cmd *cmd;
 357
 358         spin_lock_bh(&conn->cmd_lock);
 359         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 360                 if (cmd->init_task_tag == init_task_tag) {
 361                         spin_unlock_bh(&conn->cmd_lock);
 362                         return cmd;
 363                 }
 364         }
 365         spin_unlock_bh(&conn->cmd_lock);
 366
 367         pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 368                         init_task_tag, conn->cid);
 369         return NULL;
 370 }
 371
 372 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 373         struct iscsi_conn *conn,
 374         itt_t init_task_tag,
 375         u32 length)
 376 {
 377         struct iscsi_cmd *cmd;
 378
 379         spin_lock_bh(&conn->cmd_lock);
 380         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 381                 if (cmd->init_task_tag == init_task_tag) {
 382                         spin_unlock_bh(&conn->cmd_lock);
 383                         return cmd;
 384                 }
 385         }
 386         spin_unlock_bh(&conn->cmd_lock);
 387
 388         pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 389                         " dumping payload\n", init_task_tag, conn->cid);
 390         if (length)
 391                 iscsit_dump_data_payload(conn, length, 1);
 392
 393         return NULL;
 394 }
 395
 396 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 397         struct iscsi_conn *conn,
 398         u32 targ_xfer_tag)
 399 {
 400         struct iscsi_cmd *cmd = NULL;
 401
 402         spin_lock_bh(&conn->cmd_lock);
 403         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 404                 if (cmd->targ_xfer_tag == targ_xfer_tag) {
 405                         spin_unlock_bh(&conn->cmd_lock);
 406                         return cmd;
 407                 }
 408         }
 409         spin_unlock_bh(&conn->cmd_lock);
 410
 411         pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 412                         targ_xfer_tag, conn->cid);
 413         return NULL;
 414 }
 415
 416 int iscsit_find_cmd_for_recovery(
 417         struct iscsi_session *sess,
 418         struct iscsi_cmd **cmd_ptr,
 419         struct iscsi_conn_recovery **cr_ptr,
 420         itt_t init_task_tag)
 421 {
 422         struct iscsi_cmd *cmd = NULL;
 423         struct iscsi_conn_recovery *cr;
 424         /*
 425          * Scan through the inactive connection recovery list's command list.
 426          * If init_task_tag matches the command is still alligent.
 427          */
 428         spin_lock(&sess->cr_i_lock);
 429         list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 430                 spin_lock(&cr->conn_recovery_cmd_lock);
 431                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 432                         if (cmd->init_task_tag == init_task_tag) {
 433                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 434                                 spin_unlock(&sess->cr_i_lock);
 435
 436                                 *cr_ptr = cr;
 437                                 *cmd_ptr = cmd;
 438                                 return -2;
 439                         }
 440                 }
 441                 spin_unlock(&cr->conn_recovery_cmd_lock);
 442         }
 443         spin_unlock(&sess->cr_i_lock);
 444         /*
 445          * Scan through the active connection recovery list's command list.
 446          * If init_task_tag matches the command is ready to be reassigned.
 447          */
 448         spin_lock(&sess->cr_a_lock);
 449         list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 450                 spin_lock(&cr->conn_recovery_cmd_lock);
 451                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 452                         if (cmd->init_task_tag == init_task_tag) {
 453                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 454                                 spin_unlock(&sess->cr_a_lock);
 455
 456                                 *cr_ptr = cr;
 457                                 *cmd_ptr = cmd;
 458                                 return 0;
 459                         }
 460                 }
 461                 spin_unlock(&cr->conn_recovery_cmd_lock);
 462         }
 463         spin_unlock(&sess->cr_a_lock);
 464
 465         return -1;
 466 }
 467
 468 void iscsit_add_cmd_to_immediate_queue(
 469         struct iscsi_cmd *cmd,
 470         struct iscsi_conn *conn,
 471         u8 state)
 472 {
 473         struct iscsi_queue_req *qr;
 474
 475         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 476         if (!qr) {
 477                 pr_err("Unable to allocate memory for"
 478                                 " struct iscsi_queue_req\n");
 479                 return;
 480         }
 481         INIT_LIST_HEAD(&qr->qr_list);
 482         qr->cmd = cmd;
 483         qr->state = state;
 484
 485         spin_lock_bh(&conn->immed_queue_lock);
 486         list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 487         atomic_inc(&cmd->immed_queue_count);
 488         atomic_set(&conn->check_immediate_queue, 1);
 489         spin_unlock_bh(&conn->immed_queue_lock);
 490
 491         wake_up_process(conn->thread_set->tx_thread);
 492 }
 493
 494 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 495 {
 496         struct iscsi_queue_req *qr;
 497
 498         spin_lock_bh(&conn->immed_queue_lock);
 499         if (list_empty(&conn->immed_queue_list)) {
 500                 spin_unlock_bh(&conn->immed_queue_lock);
 501                 return NULL;
 502         }
 503         list_for_each_entry(qr, &conn->immed_queue_list, qr_list)
 504                 break;
 505
 506         list_del(&qr->qr_list);
 507         if (qr->cmd)
 508                 atomic_dec(&qr->cmd->immed_queue_count);
 509         spin_unlock_bh(&conn->immed_queue_lock);
 510
 511         return qr;
 512 }
 513
 514 static void iscsit_remove_cmd_from_immediate_queue(
 515         struct iscsi_cmd *cmd,
 516         struct iscsi_conn *conn)
 517 {
 518         struct iscsi_queue_req *qr, *qr_tmp;
 519
 520         spin_lock_bh(&conn->immed_queue_lock);
 521         if (!atomic_read(&cmd->immed_queue_count)) {
 522                 spin_unlock_bh(&conn->immed_queue_lock);
 523                 return;
 524         }
 525
 526         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 527                 if (qr->cmd != cmd)
 528                         continue;
 529
 530                 atomic_dec(&qr->cmd->immed_queue_count);
 531                 list_del(&qr->qr_list);
 532                 kmem_cache_free(lio_qr_cache, qr);
 533         }
 534         spin_unlock_bh(&conn->immed_queue_lock);
 535
 536         if (atomic_read(&cmd->immed_queue_count)) {
 537                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 538                         cmd->init_task_tag,
 539                         atomic_read(&cmd->immed_queue_count));
 540         }
 541 }
 542
 543 void iscsit_add_cmd_to_response_queue(
 544         struct iscsi_cmd *cmd,
 545         struct iscsi_conn *conn,
 546         u8 state)
 547 {
 548         struct iscsi_queue_req *qr;
 549
 550         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 551         if (!qr) {
 552                 pr_err("Unable to allocate memory for"
 553                         " struct iscsi_queue_req\n");
 554                 return;
 555         }
 556         INIT_LIST_HEAD(&qr->qr_list);
 557         qr->cmd = cmd;
 558         qr->state = state;
 559
 560         spin_lock_bh(&conn->response_queue_lock);
 561         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 562         atomic_inc(&cmd->response_queue_count);
 563         spin_unlock_bh(&conn->response_queue_lock);
 564
 565         wake_up_process(conn->thread_set->tx_thread);
 566 }
 567
 568 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 569 {
 570         struct iscsi_queue_req *qr;
 571
 572         spin_lock_bh(&conn->response_queue_lock);
 573         if (list_empty(&conn->response_queue_list)) {
 574                 spin_unlock_bh(&conn->response_queue_lock);
 575                 return NULL;
 576         }
 577
 578         list_for_each_entry(qr, &conn->response_queue_list, qr_list)
 579                 break;
 580
 581         list_del(&qr->qr_list);
 582         if (qr->cmd)
 583                 atomic_dec(&qr->cmd->response_queue_count);
 584         spin_unlock_bh(&conn->response_queue_lock);
 585
 586         return qr;
 587 }
 588
 589 static void iscsit_remove_cmd_from_response_queue(
 590         struct iscsi_cmd *cmd,
 591         struct iscsi_conn *conn)
 592 {
 593         struct iscsi_queue_req *qr, *qr_tmp;
 594
 595         spin_lock_bh(&conn->response_queue_lock);
 596         if (!atomic_read(&cmd->response_queue_count)) {
 597                 spin_unlock_bh(&conn->response_queue_lock);
 598                 return;
 599         }
 600
 601         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 602                                 qr_list) {
 603                 if (qr->cmd != cmd)
 604                         continue;
 605
 606                 atomic_dec(&qr->cmd->response_queue_count);
 607                 list_del(&qr->qr_list);
 608                 kmem_cache_free(lio_qr_cache, qr);
 609         }
 610         spin_unlock_bh(&conn->response_queue_lock);
 611
 612         if (atomic_read(&cmd->response_queue_count)) {
 613                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 614                         cmd->init_task_tag,
 615                         atomic_read(&cmd->response_queue_count));
 616         }
 617 }
 618
 619 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 620 {
 621         struct iscsi_queue_req *qr, *qr_tmp;
 622
 623         spin_lock_bh(&conn->immed_queue_lock);
 624         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 625                 list_del(&qr->qr_list);
 626                 if (qr->cmd)
 627                         atomic_dec(&qr->cmd->immed_queue_count);
 628
 629                 kmem_cache_free(lio_qr_cache, qr);
 630         }
 631         spin_unlock_bh(&conn->immed_queue_lock);
 632
 633         spin_lock_bh(&conn->response_queue_lock);
 634         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 635                         qr_list) {
 636                 list_del(&qr->qr_list);
 637                 if (qr->cmd)
 638                         atomic_dec(&qr->cmd->response_queue_count);
 639
 640                 kmem_cache_free(lio_qr_cache, qr);
 641         }
 642         spin_unlock_bh(&conn->response_queue_lock);
 643 }
 644
 645 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 646 {
 647         struct iscsi_conn *conn = cmd->conn;
 648
 649         iscsit_free_r2ts_from_list(cmd);
 650         iscsit_free_all_datain_reqs(cmd);
 651
 652         kfree(cmd->buf_ptr);
 653         kfree(cmd->pdu_list);
 654         kfree(cmd->seq_list);
 655         kfree(cmd->tmr_req);
 656         kfree(cmd->iov_data);
 657
 658         if (conn) {
 659                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 660                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 661         }
 662
 663         kmem_cache_free(lio_cmd_cache, cmd);
 664 }
 665
 666 void iscsit_free_cmd(struct iscsi_cmd *cmd)
 667 {
 668         /*
 669          * Determine if a struct se_cmd is associated with
 670          * this struct iscsi_cmd.
 671          */
 672         switch (cmd->iscsi_opcode) {
 673         case ISCSI_OP_SCSI_CMD:
 674         case ISCSI_OP_SCSI_TMFUNC:
 675                 transport_generic_free_cmd(&cmd->se_cmd, 1);
 676                 break;
 677         case ISCSI_OP_REJECT:
 678                 /*
 679                  * Handle special case for REJECT when iscsi_add_reject*() has
 680                  * overwritten the original iscsi_opcode assignment, and the
 681                  * associated cmd->se_cmd needs to be released.
 682                  */
 683                 if (cmd->se_cmd.se_tfo != NULL) {
 684                         transport_generic_free_cmd(&cmd->se_cmd, 1);
 685                         break;
 686                 }
 687                 /* Fall-through */
 688         default:
 689                 iscsit_release_cmd(cmd);
 690                 break;
 691         }
 692 }
 693
 694 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 695 {
 696         spin_lock_bh(&sess->session_usage_lock);
 697         if (sess->session_usage_count != 0) {
 698                 sess->session_waiting_on_uc = 1;
 699                 spin_unlock_bh(&sess->session_usage_lock);
 700                 if (in_interrupt())
 701                         return 2;
 702
 703                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 704                 return 1;
 705         }
 706         spin_unlock_bh(&sess->session_usage_lock);
 707
 708         return 0;
 709 }
 710
 711 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 712 {
 713         spin_lock_bh(&sess->session_usage_lock);
 714         sess->session_usage_count--;
 715
 716         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 717                 complete(&sess->session_waiting_on_uc_comp);
 718
 719         spin_unlock_bh(&sess->session_usage_lock);
 720 }
 721
 722 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 723 {
 724         spin_lock_bh(&sess->session_usage_lock);
 725         sess->session_usage_count++;
 726         spin_unlock_bh(&sess->session_usage_lock);
 727 }
 728
 729 /*
 730  *      Setup conn->if_marker and conn->of_marker values based upon
 731  *      the initial marker-less interval. (see iSCSI v19 A.2)
 732  */
 733 int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 734 {
 735         int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 736         /*
 737          * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 738          */
 739         u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 740         u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 741
 742         if (conn->conn_ops->OFMarker) {
 743                 /*
 744                  * Account for the first Login Command received not
 745                  * via iscsi_recv_msg().
 746                  */
 747                 conn->of_marker += ISCSI_HDR_LEN;
 748                 if (conn->of_marker <= OFMarkInt) {
 749                         conn->of_marker = (OFMarkInt - conn->of_marker);
 750                 } else {
 751                         login_ofmarker_count = (conn->of_marker / OFMarkInt);
 752                         next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 753                                         (login_ofmarker_count * MARKER_SIZE);
 754                         conn->of_marker = (next_marker - conn->of_marker);
 755                 }
 756                 conn->of_marker_offset = 0;
 757                 pr_debug("Setting OFMarker value to %u based on Initial"
 758                         " Markerless Interval.\n", conn->of_marker);
 759         }
 760
 761         if (conn->conn_ops->IFMarker) {
 762                 if (conn->if_marker <= IFMarkInt) {
 763                         conn->if_marker = (IFMarkInt - conn->if_marker);
 764                 } else {
 765                         login_ifmarker_count = (conn->if_marker / IFMarkInt);
 766                         next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 767                                         (login_ifmarker_count * MARKER_SIZE);
 768                         conn->if_marker = (next_marker - conn->if_marker);
 769                 }
 770                 pr_debug("Setting IFMarker value to %u based on Initial"
 771                         " Markerless Interval.\n", conn->if_marker);
 772         }
 773
 774         return 0;
 775 }
 776
 777 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 778 {
 779         struct iscsi_conn *conn;
 780
 781         spin_lock_bh(&sess->conn_lock);
 782         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 783                 if ((conn->cid == cid) &&
 784                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 785                         iscsit_inc_conn_usage_count(conn);
 786                         spin_unlock_bh(&sess->conn_lock);
 787                         return conn;
 788                 }
 789         }
 790         spin_unlock_bh(&sess->conn_lock);
 791
 792         return NULL;
 793 }
 794
 795 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 796 {
 797         struct iscsi_conn *conn;
 798
 799         spin_lock_bh(&sess->conn_lock);
 800         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 801                 if (conn->cid == cid) {
 802                         iscsit_inc_conn_usage_count(conn);
 803                         spin_lock(&conn->state_lock);
 804                         atomic_set(&conn->connection_wait_rcfr, 1);
 805                         spin_unlock(&conn->state_lock);
 806                         spin_unlock_bh(&sess->conn_lock);
 807                         return conn;
 808                 }
 809         }
 810         spin_unlock_bh(&sess->conn_lock);
 811
 812         return NULL;
 813 }
 814
 815 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 816 {
 817         spin_lock_bh(&conn->conn_usage_lock);
 818         if (conn->conn_usage_count != 0) {
 819                 conn->conn_waiting_on_uc = 1;
 820                 spin_unlock_bh(&conn->conn_usage_lock);
 821
 822                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 823                 return;
 824         }
 825         spin_unlock_bh(&conn->conn_usage_lock);
 826 }
 827
 828 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 829 {
 830         spin_lock_bh(&conn->conn_usage_lock);
 831         conn->conn_usage_count--;
 832
 833         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 834                 complete(&conn->conn_waiting_on_uc_comp);
 835
 836         spin_unlock_bh(&conn->conn_usage_lock);
 837 }
 838
 839 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 840 {
 841         spin_lock_bh(&conn->conn_usage_lock);
 842         conn->conn_usage_count++;
 843         spin_unlock_bh(&conn->conn_usage_lock);
 844 }
 845
 846 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 847 {
 848         u8 state;
 849         struct iscsi_cmd *cmd;
 850
 851         cmd = iscsit_allocate_cmd(conn, GFP_ATOMIC);
 852         if (!cmd)
 853                 return -1;
 854
 855         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 856         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 857                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 858         cmd->init_task_tag = RESERVED_ITT;
 859         spin_lock_bh(&conn->sess->ttt_lock);
 860         cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
 861                         0xFFFFFFFF;
 862         if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
 863                 cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
 864         spin_unlock_bh(&conn->sess->ttt_lock);
 865
 866         spin_lock_bh(&conn->cmd_lock);
 867         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 868         spin_unlock_bh(&conn->cmd_lock);
 869
 870         if (want_response)
 871                 iscsit_start_nopin_response_timer(conn);
 872         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 873
 874         return 0;
 875 }
 876
 877 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 878 {
 879         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 880
 881         iscsit_inc_conn_usage_count(conn);
 882
 883         spin_lock_bh(&conn->nopin_timer_lock);
 884         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 885                 spin_unlock_bh(&conn->nopin_timer_lock);
 886                 iscsit_dec_conn_usage_count(conn);
 887                 return;
 888         }
 889
 890         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 891                 " SID: %u, failing connection.\n", conn->cid,
 892                         conn->sess->sid);
 893         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 894         spin_unlock_bh(&conn->nopin_timer_lock);
 895
 896         {
 897         struct iscsi_portal_group *tpg = conn->sess->tpg;
 898         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 899
 900         if (tiqn) {
 901                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 902                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 903                                 conn->sess->sess_ops->InitiatorName);
 904                 tiqn->sess_err_stats.last_sess_failure_type =
 905                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 906                 tiqn->sess_err_stats.cxn_timeout_errors++;
 907                 conn->sess->conn_timeout_errors++;
 908                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 909         }
 910         }
 911
 912         iscsit_cause_connection_reinstatement(conn, 0);
 913         iscsit_dec_conn_usage_count(conn);
 914 }
 915
 916 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 917 {
 918         struct iscsi_session *sess = conn->sess;
 919         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 920
 921         spin_lock_bh(&conn->nopin_timer_lock);
 922         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 923                 spin_unlock_bh(&conn->nopin_timer_lock);
 924                 return;
 925         }
 926
 927         mod_timer(&conn->nopin_response_timer,
 928                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
 929         spin_unlock_bh(&conn->nopin_timer_lock);
 930 }
 931
 932 /*
 933  *      Called with conn->nopin_timer_lock held.
 934  */
 935 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
 936 {
 937         struct iscsi_session *sess = conn->sess;
 938         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 939
 940         spin_lock_bh(&conn->nopin_timer_lock);
 941         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
 942                 spin_unlock_bh(&conn->nopin_timer_lock);
 943                 return;
 944         }
 945
 946         init_timer(&conn->nopin_response_timer);
 947         conn->nopin_response_timer.expires =
 948                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
 949         conn->nopin_response_timer.data = (unsigned long)conn;
 950         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
 951         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
 952         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
 953         add_timer(&conn->nopin_response_timer);
 954
 955         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
 956                 " seconds\n", conn->cid, na->nopin_response_timeout);
 957         spin_unlock_bh(&conn->nopin_timer_lock);
 958 }
 959
 960 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
 961 {
 962         spin_lock_bh(&conn->nopin_timer_lock);
 963         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 964                 spin_unlock_bh(&conn->nopin_timer_lock);
 965                 return;
 966         }
 967         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
 968         spin_unlock_bh(&conn->nopin_timer_lock);
 969
 970         del_timer_sync(&conn->nopin_response_timer);
 971
 972         spin_lock_bh(&conn->nopin_timer_lock);
 973         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 974         spin_unlock_bh(&conn->nopin_timer_lock);
 975 }
 976
 977 static void iscsit_handle_nopin_timeout(unsigned long data)
 978 {
 979         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 980
 981         iscsit_inc_conn_usage_count(conn);
 982
 983         spin_lock_bh(&conn->nopin_timer_lock);
 984         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
 985                 spin_unlock_bh(&conn->nopin_timer_lock);
 986                 iscsit_dec_conn_usage_count(conn);
 987                 return;
 988         }
 989         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
 990         spin_unlock_bh(&conn->nopin_timer_lock);
 991
 992         iscsit_add_nopin(conn, 1);
 993         iscsit_dec_conn_usage_count(conn);
 994 }
 995
 996 /*
 997  * Called with conn->nopin_timer_lock held.
 998  */
 999 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1000 {
1001         struct iscsi_session *sess = conn->sess;
1002         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1003         /*
1004         * NOPIN timeout is disabled.
1005          */
1006         if (!na->nopin_timeout)
1007                 return;
1008
1009         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1010                 return;
1011
1012         init_timer(&conn->nopin_timer);
1013         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1014         conn->nopin_timer.data = (unsigned long)conn;
1015         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1016         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1017         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1018         add_timer(&conn->nopin_timer);
1019
1020         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1021                 " interval\n", conn->cid, na->nopin_timeout);
1022 }
1023
1024 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1025 {
1026         struct iscsi_session *sess = conn->sess;
1027         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1028         /*
1029          * NOPIN timeout is disabled..
1030          */
1031         if (!na->nopin_timeout)
1032                 return;
1033
1034         spin_lock_bh(&conn->nopin_timer_lock);
1035         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1036                 spin_unlock_bh(&conn->nopin_timer_lock);
1037                 return;
1038         }
1039
1040         init_timer(&conn->nopin_timer);
1041         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1042         conn->nopin_timer.data = (unsigned long)conn;
1043         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1044         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1045         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1046         add_timer(&conn->nopin_timer);
1047
1048         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1049                         " interval\n", conn->cid, na->nopin_timeout);
1050         spin_unlock_bh(&conn->nopin_timer_lock);
1051 }
1052
1053 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1054 {
1055         spin_lock_bh(&conn->nopin_timer_lock);
1056         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1057                 spin_unlock_bh(&conn->nopin_timer_lock);
1058                 return;
1059         }
1060         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1061         spin_unlock_bh(&conn->nopin_timer_lock);
1062
1063         del_timer_sync(&conn->nopin_timer);
1064
1065         spin_lock_bh(&conn->nopin_timer_lock);
1066         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1067         spin_unlock_bh(&conn->nopin_timer_lock);
1068 }
1069
1070 int iscsit_send_tx_data(
1071         struct iscsi_cmd *cmd,
1072         struct iscsi_conn *conn,
1073         int use_misc)
1074 {
1075         int tx_sent, tx_size;
1076         u32 iov_count;
1077         struct kvec *iov;
1078
1079 send_data:
1080         tx_size = cmd->tx_size;
1081
1082         if (!use_misc) {
1083                 iov = &cmd->iov_data[0];
1084                 iov_count = cmd->iov_data_count;
1085         } else {
1086                 iov = &cmd->iov_misc[0];
1087                 iov_count = cmd->iov_misc_count;
1088         }
1089
1090         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1091         if (tx_size != tx_sent) {
1092                 if (tx_sent == -EAGAIN) {
1093                         pr_err("tx_data() returned -EAGAIN\n");
1094                         goto send_data;
1095                 } else
1096                         return -1;
1097         }
1098         cmd->tx_size = 0;
1099
1100         return 0;
1101 }
1102
1103 int iscsit_fe_sendpage_sg(
1104         struct iscsi_cmd *cmd,
1105         struct iscsi_conn *conn)
1106 {
1107         struct scatterlist *sg = cmd->first_data_sg;
1108         struct kvec iov;
1109         u32 tx_hdr_size, data_len;
1110         u32 offset = cmd->first_data_sg_off;
1111         int tx_sent, iov_off;
1112
1113 send_hdr:
1114         tx_hdr_size = ISCSI_HDR_LEN;
1115         if (conn->conn_ops->HeaderDigest)
1116                 tx_hdr_size += ISCSI_CRC_LEN;
1117
1118         iov.iov_base = cmd->pdu;
1119         iov.iov_len = tx_hdr_size;
1120
1121         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1122         if (tx_hdr_size != tx_sent) {
1123                 if (tx_sent == -EAGAIN) {
1124                         pr_err("tx_data() returned -EAGAIN\n");
1125                         goto send_hdr;
1126                 }
1127                 return -1;
1128         }
1129
1130         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1131         /*
1132          * Set iov_off used by padding and data digest tx_data() calls below
1133          * in order to determine proper offset into cmd->iov_data[]
1134          */
1135         if (conn->conn_ops->DataDigest) {
1136                 data_len -= ISCSI_CRC_LEN;
1137                 if (cmd->padding)
1138                         iov_off = (cmd->iov_data_count - 2);
1139                 else
1140                         iov_off = (cmd->iov_data_count - 1);
1141         } else {
1142                 iov_off = (cmd->iov_data_count - 1);
1143         }
1144         /*
1145          * Perform sendpage() for each page in the scatterlist
1146          */
1147         while (data_len) {
1148                 u32 space = (sg->length - offset);
1149                 u32 sub_len = min_t(u32, data_len, space);
1150 send_pg:
1151                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1152                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1153                 if (tx_sent != sub_len) {
1154                         if (tx_sent == -EAGAIN) {
1155                                 pr_err("tcp_sendpage() returned"
1156                                                 " -EAGAIN\n");
1157                                 goto send_pg;
1158                         }
1159
1160                         pr_err("tcp_sendpage() failure: %d\n",
1161                                         tx_sent);
1162                         return -1;
1163                 }
1164
1165                 data_len -= sub_len;
1166                 offset = 0;
1167                 sg = sg_next(sg);
1168         }
1169
1170 send_padding:
1171         if (cmd->padding) {
1172                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1173
1174                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1175                 if (cmd->padding != tx_sent) {
1176                         if (tx_sent == -EAGAIN) {
1177                                 pr_err("tx_data() returned -EAGAIN\n");
1178                                 goto send_padding;
1179                         }
1180                         return -1;
1181                 }
1182         }
1183
1184 send_datacrc:
1185         if (conn->conn_ops->DataDigest) {
1186                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1187
1188                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1189                 if (ISCSI_CRC_LEN != tx_sent) {
1190                         if (tx_sent == -EAGAIN) {
1191                                 pr_err("tx_data() returned -EAGAIN\n");
1192                                 goto send_datacrc;
1193                         }
1194                         return -1;
1195                 }
1196         }
1197
1198         return 0;
1199 }
1200
1201 /*
1202  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1203  *      back to the Initiator when an expection condition occurs with the
1204  *      errors set in status_class and status_detail.
1205  *
1206  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1207  *      Returns:        0 on success, -1 on error.
1208  */
1209 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1210 {
1211         u8 iscsi_hdr[ISCSI_HDR_LEN];
1212         int err;
1213         struct kvec iov;
1214         struct iscsi_login_rsp *hdr;
1215
1216         iscsit_collect_login_stats(conn, status_class, status_detail);
1217
1218         memset(&iov, 0, sizeof(struct kvec));
1219         memset(&iscsi_hdr, 0x0, ISCSI_HDR_LEN);
1220
1221         hdr     = (struct iscsi_login_rsp *)&iscsi_hdr;
1222         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1223         hdr->status_class       = status_class;
1224         hdr->status_detail      = status_detail;
1225         hdr->itt                = conn->login_itt;
1226
1227         iov.iov_base            = &iscsi_hdr;
1228         iov.iov_len             = ISCSI_HDR_LEN;
1229
1230         PRINT_BUFF(iscsi_hdr, ISCSI_HDR_LEN);
1231
1232         err = tx_data(conn, &iov, 1, ISCSI_HDR_LEN);
1233         if (err != ISCSI_HDR_LEN) {
1234                 pr_err("tx_data returned less than expected\n");
1235                 return -1;
1236         }
1237
1238         return 0;
1239 }
1240
1241 void iscsit_print_session_params(struct iscsi_session *sess)
1242 {
1243         struct iscsi_conn *conn;
1244
1245         pr_debug("-----------------------------[Session Params for"
1246                 " SID: %u]-----------------------------\n", sess->sid);
1247         spin_lock_bh(&sess->conn_lock);
1248         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1249                 iscsi_dump_conn_ops(conn->conn_ops);
1250         spin_unlock_bh(&sess->conn_lock);
1251
1252         iscsi_dump_sess_ops(sess->sess_ops);
1253 }
1254
1255 static int iscsit_do_rx_data(
1256         struct iscsi_conn *conn,
1257         struct iscsi_data_count *count)
1258 {
1259         int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
1260         struct kvec *iov_p;
1261         struct msghdr msg;
1262
1263         if (!conn || !conn->sock || !conn->conn_ops)
1264                 return -1;
1265
1266         memset(&msg, 0, sizeof(struct msghdr));
1267
1268         iov_p = count->iov;
1269         iov_len = count->iov_count;
1270
1271         while (total_rx < data) {
1272                 rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
1273                                         (data - total_rx), MSG_WAITALL);
1274                 if (rx_loop <= 0) {
1275                         pr_debug("rx_loop: %d total_rx: %d\n",
1276                                 rx_loop, total_rx);
1277                         return rx_loop;
1278                 }
1279                 total_rx += rx_loop;
1280                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1281                                 rx_loop, total_rx, data);
1282         }
1283
1284         return total_rx;
1285 }
1286
1287 static int iscsit_do_tx_data(
1288         struct iscsi_conn *conn,
1289         struct iscsi_data_count *count)
1290 {
1291         int data = count->data_length, total_tx = 0, tx_loop = 0, iov_len;
1292         struct kvec *iov_p;
1293         struct msghdr msg;
1294
1295         if (!conn || !conn->sock || !conn->conn_ops)
1296                 return -1;
1297
1298         if (data <= 0) {
1299                 pr_err("Data length is: %d\n", data);
1300                 return -1;
1301         }
1302
1303         memset(&msg, 0, sizeof(struct msghdr));
1304
1305         iov_p = count->iov;
1306         iov_len = count->iov_count;
1307
1308         while (total_tx < data) {
1309                 tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1310                                         (data - total_tx));
1311                 if (tx_loop <= 0) {
1312                         pr_debug("tx_loop: %d total_tx %d\n",
1313                                 tx_loop, total_tx);
1314                         return tx_loop;
1315                 }
1316                 total_tx += tx_loop;
1317                 pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1318                                         tx_loop, total_tx, data);
1319         }
1320
1321         return total_tx;
1322 }
1323
1324 int rx_data(
1325         struct iscsi_conn *conn,
1326         struct kvec *iov,
1327         int iov_count,
1328         int data)
1329 {
1330         struct iscsi_data_count c;
1331
1332         if (!conn || !conn->sock || !conn->conn_ops)
1333                 return -1;
1334
1335         memset(&c, 0, sizeof(struct iscsi_data_count));
1336         c.iov = iov;
1337         c.iov_count = iov_count;
1338         c.data_length = data;
1339         c.type = ISCSI_RX_DATA;
1340
1341         return iscsit_do_rx_data(conn, &c);
1342 }
1343
1344 int tx_data(
1345         struct iscsi_conn *conn,
1346         struct kvec *iov,
1347         int iov_count,
1348         int data)
1349 {
1350         struct iscsi_data_count c;
1351
1352         if (!conn || !conn->sock || !conn->conn_ops)
1353                 return -1;
1354
1355         memset(&c, 0, sizeof(struct iscsi_data_count));
1356         c.iov = iov;
1357         c.iov_count = iov_count;
1358         c.data_length = data;
1359         c.type = ISCSI_TX_DATA;
1360
1361         return iscsit_do_tx_data(conn, &c);
1362 }
1363
1364 void iscsit_collect_login_stats(
1365         struct iscsi_conn *conn,
1366         u8 status_class,
1367         u8 status_detail)
1368 {
1369         struct iscsi_param *intrname = NULL;
1370         struct iscsi_tiqn *tiqn;
1371         struct iscsi_login_stats *ls;
1372
1373         tiqn = iscsit_snmp_get_tiqn(conn);
1374         if (!tiqn)
1375                 return;
1376
1377         ls = &tiqn->login_stats;
1378
1379         spin_lock(&ls->lock);
1380         if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1381             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1382                 /* We already have the failure info for this login */
1383                 spin_unlock(&ls->lock);
1384                 return;
1385         }
1386
1387         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1388                 ls->accepts++;
1389         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1390                 ls->redirects++;
1391                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1392         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1393                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1394                 ls->authenticate_fails++;
1395                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1396         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1397                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1398                 ls->authorize_fails++;
1399                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1400         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1401                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1402                 ls->negotiate_fails++;
1403                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1404         } else {
1405                 ls->other_fails++;
1406                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1407         }
1408
1409         /* Save initiator name, ip address and time, if it is a failed login */
1410         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1411                 if (conn->param_list)
1412                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1413                                                              conn->param_list);
1414                 strcpy(ls->last_intr_fail_name,
1415                        (intrname ? intrname->value : "Unknown"));
1416
1417                 ls->last_intr_fail_ip_family = conn->sock->sk->sk_family;
1418                 snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1419                                 "%s", conn->login_ip);
1420                 ls->last_fail_time = get_jiffies_64();
1421         }
1422
1423         spin_unlock(&ls->lock);
1424 }
1425
1426 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1427 {
1428         struct iscsi_portal_group *tpg;
1429
1430         if (!conn || !conn->sess)
1431                 return NULL;
1432
1433         tpg = conn->sess->tpg;
1434         if (!tpg)
1435                 return NULL;
1436
1437         if (!tpg->tpg_tiqn)
1438                 return NULL;
1439
1440         return tpg->tpg_tiqn;
1441 }