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(&conn->queues_wq);
 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(&conn->queues_wq);
 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 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 620 {
 621         bool empty;
 622
 623         spin_lock_bh(&conn->immed_queue_lock);
 624         empty = list_empty(&conn->immed_queue_list);
 625         spin_unlock_bh(&conn->immed_queue_lock);
 626
 627         if (!empty)
 628                 return empty;
 629
 630         spin_lock_bh(&conn->response_queue_lock);
 631         empty = list_empty(&conn->response_queue_list);
 632         spin_unlock_bh(&conn->response_queue_lock);
 633
 634         return empty;
 635 }
 636
 637 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 638 {
 639         struct iscsi_queue_req *qr, *qr_tmp;
 640
 641         spin_lock_bh(&conn->immed_queue_lock);
 642         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 643                 list_del(&qr->qr_list);
 644                 if (qr->cmd)
 645                         atomic_dec(&qr->cmd->immed_queue_count);
 646
 647                 kmem_cache_free(lio_qr_cache, qr);
 648         }
 649         spin_unlock_bh(&conn->immed_queue_lock);
 650
 651         spin_lock_bh(&conn->response_queue_lock);
 652         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 653                         qr_list) {
 654                 list_del(&qr->qr_list);
 655                 if (qr->cmd)
 656                         atomic_dec(&qr->cmd->response_queue_count);
 657
 658                 kmem_cache_free(lio_qr_cache, qr);
 659         }
 660         spin_unlock_bh(&conn->response_queue_lock);
 661 }
 662
 663 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 664 {
 665         struct iscsi_conn *conn = cmd->conn;
 666
 667         iscsit_free_r2ts_from_list(cmd);
 668         iscsit_free_all_datain_reqs(cmd);
 669
 670         kfree(cmd->buf_ptr);
 671         kfree(cmd->pdu_list);
 672         kfree(cmd->seq_list);
 673         kfree(cmd->tmr_req);
 674         kfree(cmd->iov_data);
 675
 676         if (conn) {
 677                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 678                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 679         }
 680
 681         kmem_cache_free(lio_cmd_cache, cmd);
 682 }
 683
 684 void iscsit_free_cmd(struct iscsi_cmd *cmd)
 685 {
 686         /*
 687          * Determine if a struct se_cmd is assoicated with
 688          * this struct iscsi_cmd.
 689          */
 690         switch (cmd->iscsi_opcode) {
 691         case ISCSI_OP_SCSI_CMD:
 692         case ISCSI_OP_SCSI_TMFUNC:
 693                 transport_generic_free_cmd(&cmd->se_cmd, 1);
 694                 break;
 695         case ISCSI_OP_REJECT:
 696                 /*
 697                  * Handle special case for REJECT when iscsi_add_reject*() has
 698                  * overwritten the original iscsi_opcode assignment, and the
 699                  * associated cmd->se_cmd needs to be released.
 700                  */
 701                 if (cmd->se_cmd.se_tfo != NULL) {
 702                         transport_generic_free_cmd(&cmd->se_cmd, 1);
 703                         break;
 704                 }
 705                 /* Fall-through */
 706         default:
 707                 iscsit_release_cmd(cmd);
 708                 break;
 709         }
 710 }
 711
 712 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 713 {
 714         spin_lock_bh(&sess->session_usage_lock);
 715         if (sess->session_usage_count != 0) {
 716                 sess->session_waiting_on_uc = 1;
 717                 spin_unlock_bh(&sess->session_usage_lock);
 718                 if (in_interrupt())
 719                         return 2;
 720
 721                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 722                 return 1;
 723         }
 724         spin_unlock_bh(&sess->session_usage_lock);
 725
 726         return 0;
 727 }
 728
 729 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 730 {
 731         spin_lock_bh(&sess->session_usage_lock);
 732         sess->session_usage_count--;
 733
 734         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 735                 complete(&sess->session_waiting_on_uc_comp);
 736
 737         spin_unlock_bh(&sess->session_usage_lock);
 738 }
 739
 740 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 741 {
 742         spin_lock_bh(&sess->session_usage_lock);
 743         sess->session_usage_count++;
 744         spin_unlock_bh(&sess->session_usage_lock);
 745 }
 746
 747 /*
 748  *      Setup conn->if_marker and conn->of_marker values based upon
 749  *      the initial marker-less interval. (see iSCSI v19 A.2)
 750  */
 751 int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 752 {
 753         int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 754         /*
 755          * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 756          */
 757         u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 758         u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 759
 760         if (conn->conn_ops->OFMarker) {
 761                 /*
 762                  * Account for the first Login Command received not
 763                  * via iscsi_recv_msg().
 764                  */
 765                 conn->of_marker += ISCSI_HDR_LEN;
 766                 if (conn->of_marker <= OFMarkInt) {
 767                         conn->of_marker = (OFMarkInt - conn->of_marker);
 768                 } else {
 769                         login_ofmarker_count = (conn->of_marker / OFMarkInt);
 770                         next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 771                                         (login_ofmarker_count * MARKER_SIZE);
 772                         conn->of_marker = (next_marker - conn->of_marker);
 773                 }
 774                 conn->of_marker_offset = 0;
 775                 pr_debug("Setting OFMarker value to %u based on Initial"
 776                         " Markerless Interval.\n", conn->of_marker);
 777         }
 778
 779         if (conn->conn_ops->IFMarker) {
 780                 if (conn->if_marker <= IFMarkInt) {
 781                         conn->if_marker = (IFMarkInt - conn->if_marker);
 782                 } else {
 783                         login_ifmarker_count = (conn->if_marker / IFMarkInt);
 784                         next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 785                                         (login_ifmarker_count * MARKER_SIZE);
 786                         conn->if_marker = (next_marker - conn->if_marker);
 787                 }
 788                 pr_debug("Setting IFMarker value to %u based on Initial"
 789                         " Markerless Interval.\n", conn->if_marker);
 790         }
 791
 792         return 0;
 793 }
 794
 795 struct iscsi_conn *iscsit_get_conn_from_cid(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                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 803                         iscsit_inc_conn_usage_count(conn);
 804                         spin_unlock_bh(&sess->conn_lock);
 805                         return conn;
 806                 }
 807         }
 808         spin_unlock_bh(&sess->conn_lock);
 809
 810         return NULL;
 811 }
 812
 813 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 814 {
 815         struct iscsi_conn *conn;
 816
 817         spin_lock_bh(&sess->conn_lock);
 818         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 819                 if (conn->cid == cid) {
 820                         iscsit_inc_conn_usage_count(conn);
 821                         spin_lock(&conn->state_lock);
 822                         atomic_set(&conn->connection_wait_rcfr, 1);
 823                         spin_unlock(&conn->state_lock);
 824                         spin_unlock_bh(&sess->conn_lock);
 825                         return conn;
 826                 }
 827         }
 828         spin_unlock_bh(&sess->conn_lock);
 829
 830         return NULL;
 831 }
 832
 833 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 834 {
 835         spin_lock_bh(&conn->conn_usage_lock);
 836         if (conn->conn_usage_count != 0) {
 837                 conn->conn_waiting_on_uc = 1;
 838                 spin_unlock_bh(&conn->conn_usage_lock);
 839
 840                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 841                 return;
 842         }
 843         spin_unlock_bh(&conn->conn_usage_lock);
 844 }
 845
 846 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 847 {
 848         spin_lock_bh(&conn->conn_usage_lock);
 849         conn->conn_usage_count--;
 850
 851         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 852                 complete(&conn->conn_waiting_on_uc_comp);
 853
 854         spin_unlock_bh(&conn->conn_usage_lock);
 855 }
 856
 857 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 858 {
 859         spin_lock_bh(&conn->conn_usage_lock);
 860         conn->conn_usage_count++;
 861         spin_unlock_bh(&conn->conn_usage_lock);
 862 }
 863
 864 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 865 {
 866         u8 state;
 867         struct iscsi_cmd *cmd;
 868
 869         cmd = iscsit_allocate_cmd(conn, GFP_ATOMIC);
 870         if (!cmd)
 871                 return -1;
 872
 873         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 874         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 875                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 876         cmd->init_task_tag = RESERVED_ITT;
 877         spin_lock_bh(&conn->sess->ttt_lock);
 878         cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
 879                         0xFFFFFFFF;
 880         if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
 881                 cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
 882         spin_unlock_bh(&conn->sess->ttt_lock);
 883
 884         spin_lock_bh(&conn->cmd_lock);
 885         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 886         spin_unlock_bh(&conn->cmd_lock);
 887
 888         if (want_response)
 889                 iscsit_start_nopin_response_timer(conn);
 890         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 891
 892         return 0;
 893 }
 894
 895 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 896 {
 897         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 898
 899         iscsit_inc_conn_usage_count(conn);
 900
 901         spin_lock_bh(&conn->nopin_timer_lock);
 902         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 903                 spin_unlock_bh(&conn->nopin_timer_lock);
 904                 iscsit_dec_conn_usage_count(conn);
 905                 return;
 906         }
 907
 908         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 909                 " SID: %u, failing connection.\n", conn->cid,
 910                         conn->sess->sid);
 911         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 912         spin_unlock_bh(&conn->nopin_timer_lock);
 913
 914         {
 915         struct iscsi_portal_group *tpg = conn->sess->tpg;
 916         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 917
 918         if (tiqn) {
 919                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 920                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 921                                 conn->sess->sess_ops->InitiatorName);
 922                 tiqn->sess_err_stats.last_sess_failure_type =
 923                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 924                 tiqn->sess_err_stats.cxn_timeout_errors++;
 925                 conn->sess->conn_timeout_errors++;
 926                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 927         }
 928         }
 929
 930         iscsit_cause_connection_reinstatement(conn, 0);
 931         iscsit_dec_conn_usage_count(conn);
 932 }
 933
 934 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 935 {
 936         struct iscsi_session *sess = conn->sess;
 937         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 938
 939         spin_lock_bh(&conn->nopin_timer_lock);
 940         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 941                 spin_unlock_bh(&conn->nopin_timer_lock);
 942                 return;
 943         }
 944
 945         mod_timer(&conn->nopin_response_timer,
 946                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
 947         spin_unlock_bh(&conn->nopin_timer_lock);
 948 }
 949
 950 /*
 951  *      Called with conn->nopin_timer_lock held.
 952  */
 953 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
 954 {
 955         struct iscsi_session *sess = conn->sess;
 956         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 957
 958         spin_lock_bh(&conn->nopin_timer_lock);
 959         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
 960                 spin_unlock_bh(&conn->nopin_timer_lock);
 961                 return;
 962         }
 963
 964         init_timer(&conn->nopin_response_timer);
 965         conn->nopin_response_timer.expires =
 966                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
 967         conn->nopin_response_timer.data = (unsigned long)conn;
 968         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
 969         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
 970         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
 971         add_timer(&conn->nopin_response_timer);
 972
 973         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
 974                 " seconds\n", conn->cid, na->nopin_response_timeout);
 975         spin_unlock_bh(&conn->nopin_timer_lock);
 976 }
 977
 978 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
 979 {
 980         spin_lock_bh(&conn->nopin_timer_lock);
 981         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 982                 spin_unlock_bh(&conn->nopin_timer_lock);
 983                 return;
 984         }
 985         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
 986         spin_unlock_bh(&conn->nopin_timer_lock);
 987
 988         del_timer_sync(&conn->nopin_response_timer);
 989
 990         spin_lock_bh(&conn->nopin_timer_lock);
 991         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 992         spin_unlock_bh(&conn->nopin_timer_lock);
 993 }
 994
 995 static void iscsit_handle_nopin_timeout(unsigned long data)
 996 {
 997         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 998
 999         iscsit_inc_conn_usage_count(conn);
1000
1001         spin_lock_bh(&conn->nopin_timer_lock);
1002         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1003                 spin_unlock_bh(&conn->nopin_timer_lock);
1004                 iscsit_dec_conn_usage_count(conn);
1005                 return;
1006         }
1007         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1008         spin_unlock_bh(&conn->nopin_timer_lock);
1009
1010         iscsit_add_nopin(conn, 1);
1011         iscsit_dec_conn_usage_count(conn);
1012 }
1013
1014 /*
1015  * Called with conn->nopin_timer_lock held.
1016  */
1017 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1018 {
1019         struct iscsi_session *sess = conn->sess;
1020         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1021         /*
1022         * NOPIN timeout is disabled.
1023          */
1024         if (!na->nopin_timeout)
1025                 return;
1026
1027         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1028                 return;
1029
1030         init_timer(&conn->nopin_timer);
1031         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1032         conn->nopin_timer.data = (unsigned long)conn;
1033         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1034         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1035         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1036         add_timer(&conn->nopin_timer);
1037
1038         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1039                 " interval\n", conn->cid, na->nopin_timeout);
1040 }
1041
1042 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1043 {
1044         struct iscsi_session *sess = conn->sess;
1045         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1046         /*
1047          * NOPIN timeout is disabled..
1048          */
1049         if (!na->nopin_timeout)
1050                 return;
1051
1052         spin_lock_bh(&conn->nopin_timer_lock);
1053         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1054                 spin_unlock_bh(&conn->nopin_timer_lock);
1055                 return;
1056         }
1057
1058         init_timer(&conn->nopin_timer);
1059         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1060         conn->nopin_timer.data = (unsigned long)conn;
1061         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1062         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1063         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1064         add_timer(&conn->nopin_timer);
1065
1066         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1067                         " interval\n", conn->cid, na->nopin_timeout);
1068         spin_unlock_bh(&conn->nopin_timer_lock);
1069 }
1070
1071 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1072 {
1073         spin_lock_bh(&conn->nopin_timer_lock);
1074         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1075                 spin_unlock_bh(&conn->nopin_timer_lock);
1076                 return;
1077         }
1078         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1079         spin_unlock_bh(&conn->nopin_timer_lock);
1080
1081         del_timer_sync(&conn->nopin_timer);
1082
1083         spin_lock_bh(&conn->nopin_timer_lock);
1084         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1085         spin_unlock_bh(&conn->nopin_timer_lock);
1086 }
1087
1088 int iscsit_send_tx_data(
1089         struct iscsi_cmd *cmd,
1090         struct iscsi_conn *conn,
1091         int use_misc)
1092 {
1093         int tx_sent, tx_size;
1094         u32 iov_count;
1095         struct kvec *iov;
1096
1097 send_data:
1098         tx_size = cmd->tx_size;
1099
1100         if (!use_misc) {
1101                 iov = &cmd->iov_data[0];
1102                 iov_count = cmd->iov_data_count;
1103         } else {
1104                 iov = &cmd->iov_misc[0];
1105                 iov_count = cmd->iov_misc_count;
1106         }
1107
1108         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1109         if (tx_size != tx_sent) {
1110                 if (tx_sent == -EAGAIN) {
1111                         pr_err("tx_data() returned -EAGAIN\n");
1112                         goto send_data;
1113                 } else
1114                         return -1;
1115         }
1116         cmd->tx_size = 0;
1117
1118         return 0;
1119 }
1120
1121 int iscsit_fe_sendpage_sg(
1122         struct iscsi_cmd *cmd,
1123         struct iscsi_conn *conn)
1124 {
1125         struct scatterlist *sg = cmd->first_data_sg;
1126         struct kvec iov;
1127         u32 tx_hdr_size, data_len;
1128         u32 offset = cmd->first_data_sg_off;
1129         int tx_sent, iov_off;
1130
1131 send_hdr:
1132         tx_hdr_size = ISCSI_HDR_LEN;
1133         if (conn->conn_ops->HeaderDigest)
1134                 tx_hdr_size += ISCSI_CRC_LEN;
1135
1136         iov.iov_base = cmd->pdu;
1137         iov.iov_len = tx_hdr_size;
1138
1139         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1140         if (tx_hdr_size != tx_sent) {
1141                 if (tx_sent == -EAGAIN) {
1142                         pr_err("tx_data() returned -EAGAIN\n");
1143                         goto send_hdr;
1144                 }
1145                 return -1;
1146         }
1147
1148         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1149         /*
1150          * Set iov_off used by padding and data digest tx_data() calls below
1151          * in order to determine proper offset into cmd->iov_data[]
1152          */
1153         if (conn->conn_ops->DataDigest) {
1154                 data_len -= ISCSI_CRC_LEN;
1155                 if (cmd->padding)
1156                         iov_off = (cmd->iov_data_count - 2);
1157                 else
1158                         iov_off = (cmd->iov_data_count - 1);
1159         } else {
1160                 iov_off = (cmd->iov_data_count - 1);
1161         }
1162         /*
1163          * Perform sendpage() for each page in the scatterlist
1164          */
1165         while (data_len) {
1166                 u32 space = (sg->length - offset);
1167                 u32 sub_len = min_t(u32, data_len, space);
1168 send_pg:
1169                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1170                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1171                 if (tx_sent != sub_len) {
1172                         if (tx_sent == -EAGAIN) {
1173                                 pr_err("tcp_sendpage() returned"
1174                                                 " -EAGAIN\n");
1175                                 goto send_pg;
1176                         }
1177
1178                         pr_err("tcp_sendpage() failure: %d\n",
1179                                         tx_sent);
1180                         return -1;
1181                 }
1182
1183                 data_len -= sub_len;
1184                 offset = 0;
1185                 sg = sg_next(sg);
1186         }
1187
1188 send_padding:
1189         if (cmd->padding) {
1190                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1191
1192                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1193                 if (cmd->padding != tx_sent) {
1194                         if (tx_sent == -EAGAIN) {
1195                                 pr_err("tx_data() returned -EAGAIN\n");
1196                                 goto send_padding;
1197                         }
1198                         return -1;
1199                 }
1200         }
1201
1202 send_datacrc:
1203         if (conn->conn_ops->DataDigest) {
1204                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1205
1206                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1207                 if (ISCSI_CRC_LEN != tx_sent) {
1208                         if (tx_sent == -EAGAIN) {
1209                                 pr_err("tx_data() returned -EAGAIN\n");
1210                                 goto send_datacrc;
1211                         }
1212                         return -1;
1213                 }
1214         }
1215
1216         return 0;
1217 }
1218
1219 /*
1220  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1221  *      back to the Initiator when an expection condition occurs with the
1222  *      errors set in status_class and status_detail.
1223  *
1224  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1225  *      Returns:        0 on success, -1 on error.
1226  */
1227 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1228 {
1229         u8 iscsi_hdr[ISCSI_HDR_LEN];
1230         int err;
1231         struct kvec iov;
1232         struct iscsi_login_rsp *hdr;
1233
1234         iscsit_collect_login_stats(conn, status_class, status_detail);
1235
1236         memset(&iov, 0, sizeof(struct kvec));
1237         memset(&iscsi_hdr, 0x0, ISCSI_HDR_LEN);
1238
1239         hdr     = (struct iscsi_login_rsp *)&iscsi_hdr;
1240         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1241         hdr->status_class       = status_class;
1242         hdr->status_detail      = status_detail;
1243         hdr->itt                = conn->login_itt;
1244
1245         iov.iov_base            = &iscsi_hdr;
1246         iov.iov_len             = ISCSI_HDR_LEN;
1247
1248         PRINT_BUFF(iscsi_hdr, ISCSI_HDR_LEN);
1249
1250         err = tx_data(conn, &iov, 1, ISCSI_HDR_LEN);
1251         if (err != ISCSI_HDR_LEN) {
1252                 pr_err("tx_data returned less than expected\n");
1253                 return -1;
1254         }
1255
1256         return 0;
1257 }
1258
1259 void iscsit_print_session_params(struct iscsi_session *sess)
1260 {
1261         struct iscsi_conn *conn;
1262
1263         pr_debug("-----------------------------[Session Params for"
1264                 " SID: %u]-----------------------------\n", sess->sid);
1265         spin_lock_bh(&sess->conn_lock);
1266         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1267                 iscsi_dump_conn_ops(conn->conn_ops);
1268         spin_unlock_bh(&sess->conn_lock);
1269
1270         iscsi_dump_sess_ops(sess->sess_ops);
1271 }
1272
1273 static int iscsit_do_rx_data(
1274         struct iscsi_conn *conn,
1275         struct iscsi_data_count *count)
1276 {
1277         int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
1278         struct kvec *iov_p;
1279         struct msghdr msg;
1280
1281         if (!conn || !conn->sock || !conn->conn_ops)
1282                 return -1;
1283
1284         memset(&msg, 0, sizeof(struct msghdr));
1285
1286         iov_p = count->iov;
1287         iov_len = count->iov_count;
1288
1289         while (total_rx < data) {
1290                 rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
1291                                         (data - total_rx), MSG_WAITALL);
1292                 if (rx_loop <= 0) {
1293                         pr_debug("rx_loop: %d total_rx: %d\n",
1294                                 rx_loop, total_rx);
1295                         return rx_loop;
1296                 }
1297                 total_rx += rx_loop;
1298                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1299                                 rx_loop, total_rx, data);
1300         }
1301
1302         return total_rx;
1303 }
1304
1305 static int iscsit_do_tx_data(
1306         struct iscsi_conn *conn,
1307         struct iscsi_data_count *count)
1308 {
1309         int data = count->data_length, total_tx = 0, tx_loop = 0, iov_len;
1310         struct kvec *iov_p;
1311         struct msghdr msg;
1312
1313         if (!conn || !conn->sock || !conn->conn_ops)
1314                 return -1;
1315
1316         if (data <= 0) {
1317                 pr_err("Data length is: %d\n", data);
1318                 return -1;
1319         }
1320
1321         memset(&msg, 0, sizeof(struct msghdr));
1322
1323         iov_p = count->iov;
1324         iov_len = count->iov_count;
1325
1326         while (total_tx < data) {
1327                 tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1328                                         (data - total_tx));
1329                 if (tx_loop <= 0) {
1330                         pr_debug("tx_loop: %d total_tx %d\n",
1331                                 tx_loop, total_tx);
1332                         return tx_loop;
1333                 }
1334                 total_tx += tx_loop;
1335                 pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1336                                         tx_loop, total_tx, data);
1337         }
1338
1339         return total_tx;
1340 }
1341
1342 int rx_data(
1343         struct iscsi_conn *conn,
1344         struct kvec *iov,
1345         int iov_count,
1346         int data)
1347 {
1348         struct iscsi_data_count c;
1349
1350         if (!conn || !conn->sock || !conn->conn_ops)
1351                 return -1;
1352
1353         memset(&c, 0, sizeof(struct iscsi_data_count));
1354         c.iov = iov;
1355         c.iov_count = iov_count;
1356         c.data_length = data;
1357         c.type = ISCSI_RX_DATA;
1358
1359         return iscsit_do_rx_data(conn, &c);
1360 }
1361
1362 int tx_data(
1363         struct iscsi_conn *conn,
1364         struct kvec *iov,
1365         int iov_count,
1366         int data)
1367 {
1368         struct iscsi_data_count c;
1369
1370         if (!conn || !conn->sock || !conn->conn_ops)
1371                 return -1;
1372
1373         memset(&c, 0, sizeof(struct iscsi_data_count));
1374         c.iov = iov;
1375         c.iov_count = iov_count;
1376         c.data_length = data;
1377         c.type = ISCSI_TX_DATA;
1378
1379         return iscsit_do_tx_data(conn, &c);
1380 }
1381
1382 void iscsit_collect_login_stats(
1383         struct iscsi_conn *conn,
1384         u8 status_class,
1385         u8 status_detail)
1386 {
1387         struct iscsi_param *intrname = NULL;
1388         struct iscsi_tiqn *tiqn;
1389         struct iscsi_login_stats *ls;
1390
1391         tiqn = iscsit_snmp_get_tiqn(conn);
1392         if (!tiqn)
1393                 return;
1394
1395         ls = &tiqn->login_stats;
1396
1397         spin_lock(&ls->lock);
1398         if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1399             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1400                 /* We already have the failure info for this login */
1401                 spin_unlock(&ls->lock);
1402                 return;
1403         }
1404
1405         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1406                 ls->accepts++;
1407         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1408                 ls->redirects++;
1409                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1410         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1411                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1412                 ls->authenticate_fails++;
1413                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1414         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1415                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1416                 ls->authorize_fails++;
1417                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1418         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1419                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1420                 ls->negotiate_fails++;
1421                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1422         } else {
1423                 ls->other_fails++;
1424                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1425         }
1426
1427         /* Save initiator name, ip address and time, if it is a failed login */
1428         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1429                 if (conn->param_list)
1430                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1431                                                              conn->param_list);
1432                 strcpy(ls->last_intr_fail_name,
1433                        (intrname ? intrname->value : "Unknown"));
1434
1435                 ls->last_intr_fail_ip_family = conn->sock->sk->sk_family;
1436                 snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1437                                 "%s", conn->login_ip);
1438                 ls->last_fail_time = get_jiffies_64();
1439         }
1440
1441         spin_unlock(&ls->lock);
1442 }
1443
1444 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1445 {
1446         struct iscsi_portal_group *tpg;
1447
1448         if (!conn || !conn->sess)
1449                 return NULL;
1450
1451         tpg = conn->sess->tpg;
1452         if (!tpg)
1453                 return NULL;
1454
1455         if (!tpg->tpg_tiqn)
1456                 return NULL;
1457
1458         return tpg->tpg_tiqn;
1459 }