drivers/target/iscsi/iscsi_target_util.c

   1 /*******************************************************************************
   2  * This file contains the iSCSI Target specific utility functions.
   3  *
   4  * (c) Copyright 2007-2013 Datera, Inc.
   5  *
   6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  ******************************************************************************/
  18
  19 #include <linux/list.h>
  20 #include <linux/percpu_ida.h>
  21 #include <net/ipv6.h>         /* ipv6_addr_equal() */
  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/iscsi/iscsi_transport.h>
  27
  28 #include <target/iscsi/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_util.h"
  37 #include "iscsi_target.h"
  38
  39 #define PRINT_BUFF(buff, len)                                   \
  40 {                                                               \
  41         int zzz;                                                \
  42                                                                 \
  43         pr_debug("%d:\n", __LINE__);                            \
  44         for (zzz = 0; zzz < len; zzz++) {                       \
  45                 if (zzz % 16 == 0) {                            \
  46                         if (zzz)                                \
  47                                 pr_debug("\n");                 \
  48                         pr_debug("%4i: ", zzz);                 \
  49                 }                                               \
  50                 pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  51         }                                                       \
  52         if ((len + 1) % 16)                                     \
  53                 pr_debug("\n");                                 \
  54 }
  55
  56 extern struct list_head g_tiqn_list;
  57 extern spinlock_t tiqn_lock;
  58
  59 /*
  60  *      Called with cmd->r2t_lock held.
  61  */
  62 int iscsit_add_r2t_to_list(
  63         struct iscsi_cmd *cmd,
  64         u32 offset,
  65         u32 xfer_len,
  66         int recovery,
  67         u32 r2t_sn)
  68 {
  69         struct iscsi_r2t *r2t;
  70
  71         r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  72         if (!r2t) {
  73                 pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  74                 return -1;
  75         }
  76         INIT_LIST_HEAD(&r2t->r2t_list);
  77
  78         r2t->recovery_r2t = recovery;
  79         r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  80         r2t->offset = offset;
  81         r2t->xfer_len = xfer_len;
  82         list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  83         spin_unlock_bh(&cmd->r2t_lock);
  84
  85         iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  86
  87         spin_lock_bh(&cmd->r2t_lock);
  88         return 0;
  89 }
  90
  91 struct iscsi_r2t *iscsit_get_r2t_for_eos(
  92         struct iscsi_cmd *cmd,
  93         u32 offset,
  94         u32 length)
  95 {
  96         struct iscsi_r2t *r2t;
  97
  98         spin_lock_bh(&cmd->r2t_lock);
  99         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 100                 if ((r2t->offset <= offset) &&
 101                     (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 102                         spin_unlock_bh(&cmd->r2t_lock);
 103                         return r2t;
 104                 }
 105         }
 106         spin_unlock_bh(&cmd->r2t_lock);
 107
 108         pr_err("Unable to locate R2T for Offset: %u, Length:"
 109                         " %u\n", offset, length);
 110         return NULL;
 111 }
 112
 113 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 114 {
 115         struct iscsi_r2t *r2t;
 116
 117         spin_lock_bh(&cmd->r2t_lock);
 118         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 119                 if (!r2t->sent_r2t) {
 120                         spin_unlock_bh(&cmd->r2t_lock);
 121                         return r2t;
 122                 }
 123         }
 124         spin_unlock_bh(&cmd->r2t_lock);
 125
 126         pr_err("Unable to locate next R2T to send for ITT:"
 127                         " 0x%08x.\n", cmd->init_task_tag);
 128         return NULL;
 129 }
 130
 131 /*
 132  *      Called with cmd->r2t_lock held.
 133  */
 134 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 135 {
 136         list_del(&r2t->r2t_list);
 137         kmem_cache_free(lio_r2t_cache, r2t);
 138 }
 139
 140 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 141 {
 142         struct iscsi_r2t *r2t, *r2t_tmp;
 143
 144         spin_lock_bh(&cmd->r2t_lock);
 145         list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 146                 iscsit_free_r2t(r2t, cmd);
 147         spin_unlock_bh(&cmd->r2t_lock);
 148 }
 149
 150 /*
 151  * May be called from software interrupt (timer) context for allocating
 152  * iSCSI NopINs.
 153  */
 154 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, int state)
 155 {
 156         struct iscsi_cmd *cmd;
 157         struct se_session *se_sess = conn->sess->se_sess;
 158         int size, tag;
 159
 160         tag = percpu_ida_alloc(&se_sess->sess_tag_pool, state);
 161         if (tag < 0)
 162                 return NULL;
 163
 164         size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
 165         cmd = (struct iscsi_cmd *)(se_sess->sess_cmd_map + (tag * size));
 166         memset(cmd, 0, size);
 167
 168         cmd->se_cmd.map_tag = tag;
 169         cmd->conn = conn;
 170         cmd->data_direction = DMA_NONE;
 171         INIT_LIST_HEAD(&cmd->i_conn_node);
 172         INIT_LIST_HEAD(&cmd->datain_list);
 173         INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 174         spin_lock_init(&cmd->datain_lock);
 175         spin_lock_init(&cmd->dataout_timeout_lock);
 176         spin_lock_init(&cmd->istate_lock);
 177         spin_lock_init(&cmd->error_lock);
 178         spin_lock_init(&cmd->r2t_lock);
 179         timer_setup(&cmd->dataout_timer, iscsit_handle_dataout_timeout, 0);
 180
 181         return cmd;
 182 }
 183 EXPORT_SYMBOL(iscsit_allocate_cmd);
 184
 185 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 186         struct iscsi_cmd *cmd,
 187         u32 seq_send_order)
 188 {
 189         u32 i;
 190
 191         for (i = 0; i < cmd->seq_count; i++)
 192                 if (cmd->seq_list[i].seq_send_order == seq_send_order)
 193                         return &cmd->seq_list[i];
 194
 195         return NULL;
 196 }
 197
 198 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 199 {
 200         u32 i;
 201
 202         if (!cmd->seq_list) {
 203                 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 204                 return NULL;
 205         }
 206
 207         for (i = 0; i < cmd->seq_count; i++) {
 208                 if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 209                         continue;
 210                 if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 211                         cmd->seq_send_order++;
 212                         return &cmd->seq_list[i];
 213                 }
 214         }
 215
 216         return NULL;
 217 }
 218
 219 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 220         struct iscsi_cmd *cmd,
 221         u32 r2t_sn)
 222 {
 223         struct iscsi_r2t *r2t;
 224
 225         spin_lock_bh(&cmd->r2t_lock);
 226         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 227                 if (r2t->r2t_sn == r2t_sn) {
 228                         spin_unlock_bh(&cmd->r2t_lock);
 229                         return r2t;
 230                 }
 231         }
 232         spin_unlock_bh(&cmd->r2t_lock);
 233
 234         return NULL;
 235 }
 236
 237 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 238 {
 239         u32 max_cmdsn;
 240         int ret;
 241
 242         /*
 243          * This is the proper method of checking received CmdSN against
 244          * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 245          * or order CmdSNs due to multiple connection sessions and/or
 246          * CRC failures.
 247          */
 248         max_cmdsn = atomic_read(&sess->max_cmd_sn);
 249         if (iscsi_sna_gt(cmdsn, max_cmdsn)) {
 250                 pr_err("Received CmdSN: 0x%08x is greater than"
 251                        " MaxCmdSN: 0x%08x, ignoring.\n", cmdsn, max_cmdsn);
 252                 ret = CMDSN_MAXCMDSN_OVERRUN;
 253
 254         } else if (cmdsn == sess->exp_cmd_sn) {
 255                 sess->exp_cmd_sn++;
 256                 pr_debug("Received CmdSN matches ExpCmdSN,"
 257                       " incremented ExpCmdSN to: 0x%08x\n",
 258                       sess->exp_cmd_sn);
 259                 ret = CMDSN_NORMAL_OPERATION;
 260
 261         } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 262                 pr_debug("Received CmdSN: 0x%08x is greater"
 263                       " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 264                       cmdsn, sess->exp_cmd_sn);
 265                 ret = CMDSN_HIGHER_THAN_EXP;
 266
 267         } else {
 268                 pr_err("Received CmdSN: 0x%08x is less than"
 269                        " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 270                        sess->exp_cmd_sn);
 271                 ret = CMDSN_LOWER_THAN_EXP;
 272         }
 273
 274         return ret;
 275 }
 276
 277 /*
 278  * Commands may be received out of order if MC/S is in use.
 279  * Ensure they are executed in CmdSN order.
 280  */
 281 int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 282                         unsigned char *buf, __be32 cmdsn)
 283 {
 284         int ret, cmdsn_ret;
 285         bool reject = false;
 286         u8 reason = ISCSI_REASON_BOOKMARK_NO_RESOURCES;
 287
 288         mutex_lock(&conn->sess->cmdsn_mutex);
 289
 290         cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
 291         switch (cmdsn_ret) {
 292         case CMDSN_NORMAL_OPERATION:
 293                 ret = iscsit_execute_cmd(cmd, 0);
 294                 if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 295                         iscsit_execute_ooo_cmdsns(conn->sess);
 296                 else if (ret < 0) {
 297                         reject = true;
 298                         ret = CMDSN_ERROR_CANNOT_RECOVER;
 299                 }
 300                 break;
 301         case CMDSN_HIGHER_THAN_EXP:
 302                 ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
 303                 if (ret < 0) {
 304                         reject = true;
 305                         ret = CMDSN_ERROR_CANNOT_RECOVER;
 306                         break;
 307                 }
 308                 ret = CMDSN_HIGHER_THAN_EXP;
 309                 break;
 310         case CMDSN_LOWER_THAN_EXP:
 311         case CMDSN_MAXCMDSN_OVERRUN:
 312         default:
 313                 cmd->i_state = ISTATE_REMOVE;
 314                 iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 315                 /*
 316                  * Existing callers for iscsit_sequence_cmd() will silently
 317                  * ignore commands with CMDSN_LOWER_THAN_EXP, so force this
 318                  * return for CMDSN_MAXCMDSN_OVERRUN as well..
 319                  */
 320                 ret = CMDSN_LOWER_THAN_EXP;
 321                 break;
 322         }
 323         mutex_unlock(&conn->sess->cmdsn_mutex);
 324
 325         if (reject)
 326                 iscsit_reject_cmd(cmd, reason, buf);
 327
 328         return ret;
 329 }
 330 EXPORT_SYMBOL(iscsit_sequence_cmd);
 331
 332 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 333 {
 334         struct iscsi_conn *conn = cmd->conn;
 335         struct se_cmd *se_cmd = &cmd->se_cmd;
 336         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 337         u32 payload_length = ntoh24(hdr->dlength);
 338
 339         if (conn->sess->sess_ops->InitialR2T) {
 340                 pr_err("Received unexpected unsolicited data"
 341                         " while InitialR2T=Yes, protocol error.\n");
 342                 transport_send_check_condition_and_sense(se_cmd,
 343                                 TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 344                 return -1;
 345         }
 346
 347         if ((cmd->first_burst_len + payload_length) >
 348              conn->sess->sess_ops->FirstBurstLength) {
 349                 pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 350                         " for this Unsolicited DataOut Burst.\n",
 351                         (cmd->first_burst_len + payload_length),
 352                                 conn->sess->sess_ops->FirstBurstLength);
 353                 transport_send_check_condition_and_sense(se_cmd,
 354                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 355                 return -1;
 356         }
 357
 358         if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 359                 return 0;
 360
 361         if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 362             ((cmd->first_burst_len + payload_length) !=
 363               conn->sess->sess_ops->FirstBurstLength)) {
 364                 pr_err("Unsolicited non-immediate data received %u"
 365                         " does not equal FirstBurstLength: %u, and does"
 366                         " not equal ExpXferLen %u.\n",
 367                         (cmd->first_burst_len + payload_length),
 368                         conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 369                 transport_send_check_condition_and_sense(se_cmd,
 370                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 371                 return -1;
 372         }
 373         return 0;
 374 }
 375
 376 struct iscsi_cmd *iscsit_find_cmd_from_itt(
 377         struct iscsi_conn *conn,
 378         itt_t init_task_tag)
 379 {
 380         struct iscsi_cmd *cmd;
 381
 382         spin_lock_bh(&conn->cmd_lock);
 383         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 384                 if (cmd->init_task_tag == init_task_tag) {
 385                         spin_unlock_bh(&conn->cmd_lock);
 386                         return cmd;
 387                 }
 388         }
 389         spin_unlock_bh(&conn->cmd_lock);
 390
 391         pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 392                         init_task_tag, conn->cid);
 393         return NULL;
 394 }
 395 EXPORT_SYMBOL(iscsit_find_cmd_from_itt);
 396
 397 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 398         struct iscsi_conn *conn,
 399         itt_t init_task_tag,
 400         u32 length)
 401 {
 402         struct iscsi_cmd *cmd;
 403
 404         spin_lock_bh(&conn->cmd_lock);
 405         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 406                 if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT)
 407                         continue;
 408                 if (cmd->init_task_tag == init_task_tag) {
 409                         spin_unlock_bh(&conn->cmd_lock);
 410                         return cmd;
 411                 }
 412         }
 413         spin_unlock_bh(&conn->cmd_lock);
 414
 415         pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 416                         " dumping payload\n", init_task_tag, conn->cid);
 417         if (length)
 418                 iscsit_dump_data_payload(conn, length, 1);
 419
 420         return NULL;
 421 }
 422 EXPORT_SYMBOL(iscsit_find_cmd_from_itt_or_dump);
 423
 424 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 425         struct iscsi_conn *conn,
 426         u32 targ_xfer_tag)
 427 {
 428         struct iscsi_cmd *cmd = NULL;
 429
 430         spin_lock_bh(&conn->cmd_lock);
 431         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 432                 if (cmd->targ_xfer_tag == targ_xfer_tag) {
 433                         spin_unlock_bh(&conn->cmd_lock);
 434                         return cmd;
 435                 }
 436         }
 437         spin_unlock_bh(&conn->cmd_lock);
 438
 439         pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 440                         targ_xfer_tag, conn->cid);
 441         return NULL;
 442 }
 443
 444 int iscsit_find_cmd_for_recovery(
 445         struct iscsi_session *sess,
 446         struct iscsi_cmd **cmd_ptr,
 447         struct iscsi_conn_recovery **cr_ptr,
 448         itt_t init_task_tag)
 449 {
 450         struct iscsi_cmd *cmd = NULL;
 451         struct iscsi_conn_recovery *cr;
 452         /*
 453          * Scan through the inactive connection recovery list's command list.
 454          * If init_task_tag matches the command is still alligent.
 455          */
 456         spin_lock(&sess->cr_i_lock);
 457         list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 458                 spin_lock(&cr->conn_recovery_cmd_lock);
 459                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 460                         if (cmd->init_task_tag == init_task_tag) {
 461                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 462                                 spin_unlock(&sess->cr_i_lock);
 463
 464                                 *cr_ptr = cr;
 465                                 *cmd_ptr = cmd;
 466                                 return -2;
 467                         }
 468                 }
 469                 spin_unlock(&cr->conn_recovery_cmd_lock);
 470         }
 471         spin_unlock(&sess->cr_i_lock);
 472         /*
 473          * Scan through the active connection recovery list's command list.
 474          * If init_task_tag matches the command is ready to be reassigned.
 475          */
 476         spin_lock(&sess->cr_a_lock);
 477         list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 478                 spin_lock(&cr->conn_recovery_cmd_lock);
 479                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 480                         if (cmd->init_task_tag == init_task_tag) {
 481                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 482                                 spin_unlock(&sess->cr_a_lock);
 483
 484                                 *cr_ptr = cr;
 485                                 *cmd_ptr = cmd;
 486                                 return 0;
 487                         }
 488                 }
 489                 spin_unlock(&cr->conn_recovery_cmd_lock);
 490         }
 491         spin_unlock(&sess->cr_a_lock);
 492
 493         return -1;
 494 }
 495
 496 void iscsit_add_cmd_to_immediate_queue(
 497         struct iscsi_cmd *cmd,
 498         struct iscsi_conn *conn,
 499         u8 state)
 500 {
 501         struct iscsi_queue_req *qr;
 502
 503         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 504         if (!qr) {
 505                 pr_err("Unable to allocate memory for"
 506                                 " struct iscsi_queue_req\n");
 507                 return;
 508         }
 509         INIT_LIST_HEAD(&qr->qr_list);
 510         qr->cmd = cmd;
 511         qr->state = state;
 512
 513         spin_lock_bh(&conn->immed_queue_lock);
 514         list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 515         atomic_inc(&cmd->immed_queue_count);
 516         atomic_set(&conn->check_immediate_queue, 1);
 517         spin_unlock_bh(&conn->immed_queue_lock);
 518
 519         wake_up(&conn->queues_wq);
 520 }
 521 EXPORT_SYMBOL(iscsit_add_cmd_to_immediate_queue);
 522
 523 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 524 {
 525         struct iscsi_queue_req *qr;
 526
 527         spin_lock_bh(&conn->immed_queue_lock);
 528         if (list_empty(&conn->immed_queue_list)) {
 529                 spin_unlock_bh(&conn->immed_queue_lock);
 530                 return NULL;
 531         }
 532         qr = list_first_entry(&conn->immed_queue_list,
 533                               struct iscsi_queue_req, qr_list);
 534
 535         list_del(&qr->qr_list);
 536         if (qr->cmd)
 537                 atomic_dec(&qr->cmd->immed_queue_count);
 538         spin_unlock_bh(&conn->immed_queue_lock);
 539
 540         return qr;
 541 }
 542
 543 static void iscsit_remove_cmd_from_immediate_queue(
 544         struct iscsi_cmd *cmd,
 545         struct iscsi_conn *conn)
 546 {
 547         struct iscsi_queue_req *qr, *qr_tmp;
 548
 549         spin_lock_bh(&conn->immed_queue_lock);
 550         if (!atomic_read(&cmd->immed_queue_count)) {
 551                 spin_unlock_bh(&conn->immed_queue_lock);
 552                 return;
 553         }
 554
 555         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 556                 if (qr->cmd != cmd)
 557                         continue;
 558
 559                 atomic_dec(&qr->cmd->immed_queue_count);
 560                 list_del(&qr->qr_list);
 561                 kmem_cache_free(lio_qr_cache, qr);
 562         }
 563         spin_unlock_bh(&conn->immed_queue_lock);
 564
 565         if (atomic_read(&cmd->immed_queue_count)) {
 566                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 567                         cmd->init_task_tag,
 568                         atomic_read(&cmd->immed_queue_count));
 569         }
 570 }
 571
 572 int iscsit_add_cmd_to_response_queue(
 573         struct iscsi_cmd *cmd,
 574         struct iscsi_conn *conn,
 575         u8 state)
 576 {
 577         struct iscsi_queue_req *qr;
 578
 579         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 580         if (!qr) {
 581                 pr_err("Unable to allocate memory for"
 582                         " struct iscsi_queue_req\n");
 583                 return -ENOMEM;
 584         }
 585         INIT_LIST_HEAD(&qr->qr_list);
 586         qr->cmd = cmd;
 587         qr->state = state;
 588
 589         spin_lock_bh(&conn->response_queue_lock);
 590         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 591         atomic_inc(&cmd->response_queue_count);
 592         spin_unlock_bh(&conn->response_queue_lock);
 593
 594         wake_up(&conn->queues_wq);
 595         return 0;
 596 }
 597
 598 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 599 {
 600         struct iscsi_queue_req *qr;
 601
 602         spin_lock_bh(&conn->response_queue_lock);
 603         if (list_empty(&conn->response_queue_list)) {
 604                 spin_unlock_bh(&conn->response_queue_lock);
 605                 return NULL;
 606         }
 607
 608         qr = list_first_entry(&conn->response_queue_list,
 609                               struct iscsi_queue_req, qr_list);
 610
 611         list_del(&qr->qr_list);
 612         if (qr->cmd)
 613                 atomic_dec(&qr->cmd->response_queue_count);
 614         spin_unlock_bh(&conn->response_queue_lock);
 615
 616         return qr;
 617 }
 618
 619 static void iscsit_remove_cmd_from_response_queue(
 620         struct iscsi_cmd *cmd,
 621         struct iscsi_conn *conn)
 622 {
 623         struct iscsi_queue_req *qr, *qr_tmp;
 624
 625         spin_lock_bh(&conn->response_queue_lock);
 626         if (!atomic_read(&cmd->response_queue_count)) {
 627                 spin_unlock_bh(&conn->response_queue_lock);
 628                 return;
 629         }
 630
 631         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 632                                 qr_list) {
 633                 if (qr->cmd != cmd)
 634                         continue;
 635
 636                 atomic_dec(&qr->cmd->response_queue_count);
 637                 list_del(&qr->qr_list);
 638                 kmem_cache_free(lio_qr_cache, qr);
 639         }
 640         spin_unlock_bh(&conn->response_queue_lock);
 641
 642         if (atomic_read(&cmd->response_queue_count)) {
 643                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 644                         cmd->init_task_tag,
 645                         atomic_read(&cmd->response_queue_count));
 646         }
 647 }
 648
 649 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 650 {
 651         bool empty;
 652
 653         spin_lock_bh(&conn->immed_queue_lock);
 654         empty = list_empty(&conn->immed_queue_list);
 655         spin_unlock_bh(&conn->immed_queue_lock);
 656
 657         if (!empty)
 658                 return empty;
 659
 660         spin_lock_bh(&conn->response_queue_lock);
 661         empty = list_empty(&conn->response_queue_list);
 662         spin_unlock_bh(&conn->response_queue_lock);
 663
 664         return empty;
 665 }
 666
 667 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 668 {
 669         struct iscsi_queue_req *qr, *qr_tmp;
 670
 671         spin_lock_bh(&conn->immed_queue_lock);
 672         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 673                 list_del(&qr->qr_list);
 674                 if (qr->cmd)
 675                         atomic_dec(&qr->cmd->immed_queue_count);
 676
 677                 kmem_cache_free(lio_qr_cache, qr);
 678         }
 679         spin_unlock_bh(&conn->immed_queue_lock);
 680
 681         spin_lock_bh(&conn->response_queue_lock);
 682         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 683                         qr_list) {
 684                 list_del(&qr->qr_list);
 685                 if (qr->cmd)
 686                         atomic_dec(&qr->cmd->response_queue_count);
 687
 688                 kmem_cache_free(lio_qr_cache, qr);
 689         }
 690         spin_unlock_bh(&conn->response_queue_lock);
 691 }
 692
 693 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 694 {
 695         struct iscsi_session *sess;
 696         struct se_cmd *se_cmd = &cmd->se_cmd;
 697
 698         WARN_ON(!list_empty(&cmd->i_conn_node));
 699
 700         if (cmd->conn)
 701                 sess = cmd->conn->sess;
 702         else
 703                 sess = cmd->sess;
 704
 705         BUG_ON(!sess || !sess->se_sess);
 706
 707         kfree(cmd->buf_ptr);
 708         kfree(cmd->pdu_list);
 709         kfree(cmd->seq_list);
 710         kfree(cmd->tmr_req);
 711         kfree(cmd->iov_data);
 712         kfree(cmd->text_in_ptr);
 713
 714         percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 715 }
 716 EXPORT_SYMBOL(iscsit_release_cmd);
 717
 718 void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool check_queues)
 719 {
 720         struct iscsi_conn *conn = cmd->conn;
 721
 722         WARN_ON(!list_empty(&cmd->i_conn_node));
 723
 724         if (cmd->data_direction == DMA_TO_DEVICE) {
 725                 iscsit_stop_dataout_timer(cmd);
 726                 iscsit_free_r2ts_from_list(cmd);
 727         }
 728         if (cmd->data_direction == DMA_FROM_DEVICE)
 729                 iscsit_free_all_datain_reqs(cmd);
 730
 731         if (conn && check_queues) {
 732                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 733                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 734         }
 735
 736         if (conn && conn->conn_transport->iscsit_release_cmd)
 737                 conn->conn_transport->iscsit_release_cmd(conn, cmd);
 738 }
 739
 740 void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 741 {
 742         struct se_cmd *se_cmd = cmd->se_cmd.se_tfo ? &cmd->se_cmd : NULL;
 743         int rc;
 744
 745         __iscsit_free_cmd(cmd, shutdown);
 746         if (se_cmd) {
 747                 rc = transport_generic_free_cmd(se_cmd, shutdown);
 748                 if (!rc && shutdown && se_cmd->se_sess) {
 749                         __iscsit_free_cmd(cmd, shutdown);
 750                         target_put_sess_cmd(se_cmd);
 751                 }
 752         } else {
 753                 iscsit_release_cmd(cmd);
 754         }
 755 }
 756 EXPORT_SYMBOL(iscsit_free_cmd);
 757
 758 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 759 {
 760         spin_lock_bh(&sess->session_usage_lock);
 761         if (sess->session_usage_count != 0) {
 762                 sess->session_waiting_on_uc = 1;
 763                 spin_unlock_bh(&sess->session_usage_lock);
 764                 if (in_interrupt())
 765                         return 2;
 766
 767                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 768                 return 1;
 769         }
 770         spin_unlock_bh(&sess->session_usage_lock);
 771
 772         return 0;
 773 }
 774
 775 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 776 {
 777         spin_lock_bh(&sess->session_usage_lock);
 778         sess->session_usage_count--;
 779
 780         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 781                 complete(&sess->session_waiting_on_uc_comp);
 782
 783         spin_unlock_bh(&sess->session_usage_lock);
 784 }
 785
 786 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 787 {
 788         spin_lock_bh(&sess->session_usage_lock);
 789         sess->session_usage_count++;
 790         spin_unlock_bh(&sess->session_usage_lock);
 791 }
 792
 793 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 794 {
 795         struct iscsi_conn *conn;
 796
 797         spin_lock_bh(&sess->conn_lock);
 798         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 799                 if ((conn->cid == cid) &&
 800                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 801                         iscsit_inc_conn_usage_count(conn);
 802                         spin_unlock_bh(&sess->conn_lock);
 803                         return conn;
 804                 }
 805         }
 806         spin_unlock_bh(&sess->conn_lock);
 807
 808         return NULL;
 809 }
 810
 811 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 812 {
 813         struct iscsi_conn *conn;
 814
 815         spin_lock_bh(&sess->conn_lock);
 816         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 817                 if (conn->cid == cid) {
 818                         iscsit_inc_conn_usage_count(conn);
 819                         spin_lock(&conn->state_lock);
 820                         atomic_set(&conn->connection_wait_rcfr, 1);
 821                         spin_unlock(&conn->state_lock);
 822                         spin_unlock_bh(&sess->conn_lock);
 823                         return conn;
 824                 }
 825         }
 826         spin_unlock_bh(&sess->conn_lock);
 827
 828         return NULL;
 829 }
 830
 831 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 832 {
 833         spin_lock_bh(&conn->conn_usage_lock);
 834         if (conn->conn_usage_count != 0) {
 835                 conn->conn_waiting_on_uc = 1;
 836                 spin_unlock_bh(&conn->conn_usage_lock);
 837
 838                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 839                 return;
 840         }
 841         spin_unlock_bh(&conn->conn_usage_lock);
 842 }
 843
 844 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 845 {
 846         spin_lock_bh(&conn->conn_usage_lock);
 847         conn->conn_usage_count--;
 848
 849         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 850                 complete(&conn->conn_waiting_on_uc_comp);
 851
 852         spin_unlock_bh(&conn->conn_usage_lock);
 853 }
 854
 855 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 856 {
 857         spin_lock_bh(&conn->conn_usage_lock);
 858         conn->conn_usage_count++;
 859         spin_unlock_bh(&conn->conn_usage_lock);
 860 }
 861
 862 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 863 {
 864         u8 state;
 865         struct iscsi_cmd *cmd;
 866
 867         cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
 868         if (!cmd)
 869                 return -1;
 870
 871         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 872         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 873                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 874         cmd->init_task_tag = RESERVED_ITT;
 875         cmd->targ_xfer_tag = (want_response) ?
 876                              session_get_next_ttt(conn->sess) : 0xFFFFFFFF;
 877         spin_lock_bh(&conn->cmd_lock);
 878         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 879         spin_unlock_bh(&conn->cmd_lock);
 880
 881         if (want_response)
 882                 iscsit_start_nopin_response_timer(conn);
 883         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 884
 885         return 0;
 886 }
 887
 888 void iscsit_handle_nopin_response_timeout(struct timer_list *t)
 889 {
 890         struct iscsi_conn *conn = from_timer(conn, t, nopin_response_timer);
 891
 892         iscsit_inc_conn_usage_count(conn);
 893
 894         spin_lock_bh(&conn->nopin_timer_lock);
 895         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 896                 spin_unlock_bh(&conn->nopin_timer_lock);
 897                 iscsit_dec_conn_usage_count(conn);
 898                 return;
 899         }
 900
 901         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 902                 " SID: %u, failing connection.\n", conn->cid,
 903                         conn->sess->sid);
 904         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 905         spin_unlock_bh(&conn->nopin_timer_lock);
 906
 907         {
 908         struct iscsi_portal_group *tpg = conn->sess->tpg;
 909         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 910
 911         if (tiqn) {
 912                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 913                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 914                                 conn->sess->sess_ops->InitiatorName);
 915                 tiqn->sess_err_stats.last_sess_failure_type =
 916                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 917                 tiqn->sess_err_stats.cxn_timeout_errors++;
 918                 atomic_long_inc(&conn->sess->conn_timeout_errors);
 919                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 920         }
 921         }
 922
 923         iscsit_cause_connection_reinstatement(conn, 0);
 924         iscsit_dec_conn_usage_count(conn);
 925 }
 926
 927 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 928 {
 929         struct iscsi_session *sess = conn->sess;
 930         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 931
 932         spin_lock_bh(&conn->nopin_timer_lock);
 933         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 934                 spin_unlock_bh(&conn->nopin_timer_lock);
 935                 return;
 936         }
 937
 938         mod_timer(&conn->nopin_response_timer,
 939                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
 940         spin_unlock_bh(&conn->nopin_timer_lock);
 941 }
 942
 943 /*
 944  *      Called with conn->nopin_timer_lock held.
 945  */
 946 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
 947 {
 948         struct iscsi_session *sess = conn->sess;
 949         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 950
 951         spin_lock_bh(&conn->nopin_timer_lock);
 952         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
 953                 spin_unlock_bh(&conn->nopin_timer_lock);
 954                 return;
 955         }
 956
 957         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
 958         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
 959         mod_timer(&conn->nopin_response_timer,
 960                   jiffies + na->nopin_response_timeout * HZ);
 961
 962         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
 963                 " seconds\n", conn->cid, na->nopin_response_timeout);
 964         spin_unlock_bh(&conn->nopin_timer_lock);
 965 }
 966
 967 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
 968 {
 969         spin_lock_bh(&conn->nopin_timer_lock);
 970         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 971                 spin_unlock_bh(&conn->nopin_timer_lock);
 972                 return;
 973         }
 974         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
 975         spin_unlock_bh(&conn->nopin_timer_lock);
 976
 977         del_timer_sync(&conn->nopin_response_timer);
 978
 979         spin_lock_bh(&conn->nopin_timer_lock);
 980         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 981         spin_unlock_bh(&conn->nopin_timer_lock);
 982 }
 983
 984 void iscsit_handle_nopin_timeout(struct timer_list *t)
 985 {
 986         struct iscsi_conn *conn = from_timer(conn, t, nopin_timer);
 987
 988         iscsit_inc_conn_usage_count(conn);
 989
 990         spin_lock_bh(&conn->nopin_timer_lock);
 991         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
 992                 spin_unlock_bh(&conn->nopin_timer_lock);
 993                 iscsit_dec_conn_usage_count(conn);
 994                 return;
 995         }
 996         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
 997         spin_unlock_bh(&conn->nopin_timer_lock);
 998
 999         iscsit_add_nopin(conn, 1);
1000         iscsit_dec_conn_usage_count(conn);
1001 }
1002
1003 /*
1004  * Called with conn->nopin_timer_lock held.
1005  */
1006 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1007 {
1008         struct iscsi_session *sess = conn->sess;
1009         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1010         /*
1011         * NOPIN timeout is disabled.
1012          */
1013         if (!na->nopin_timeout)
1014                 return;
1015
1016         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1017                 return;
1018
1019         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1020         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1021         mod_timer(&conn->nopin_timer, jiffies + na->nopin_timeout * HZ);
1022
1023         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1024                 " interval\n", conn->cid, na->nopin_timeout);
1025 }
1026
1027 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1028 {
1029         struct iscsi_session *sess = conn->sess;
1030         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1031         /*
1032          * NOPIN timeout is disabled..
1033          */
1034         if (!na->nopin_timeout)
1035                 return;
1036
1037         spin_lock_bh(&conn->nopin_timer_lock);
1038         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1039                 spin_unlock_bh(&conn->nopin_timer_lock);
1040                 return;
1041         }
1042
1043         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1044         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1045         mod_timer(&conn->nopin_timer, jiffies + na->nopin_timeout * HZ);
1046
1047         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1048                         " interval\n", conn->cid, na->nopin_timeout);
1049         spin_unlock_bh(&conn->nopin_timer_lock);
1050 }
1051
1052 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1053 {
1054         spin_lock_bh(&conn->nopin_timer_lock);
1055         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1056                 spin_unlock_bh(&conn->nopin_timer_lock);
1057                 return;
1058         }
1059         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1060         spin_unlock_bh(&conn->nopin_timer_lock);
1061
1062         del_timer_sync(&conn->nopin_timer);
1063
1064         spin_lock_bh(&conn->nopin_timer_lock);
1065         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1066         spin_unlock_bh(&conn->nopin_timer_lock);
1067 }
1068
1069 int iscsit_send_tx_data(
1070         struct iscsi_cmd *cmd,
1071         struct iscsi_conn *conn,
1072         int use_misc)
1073 {
1074         int tx_sent, tx_size;
1075         u32 iov_count;
1076         struct kvec *iov;
1077
1078 send_data:
1079         tx_size = cmd->tx_size;
1080
1081         if (!use_misc) {
1082                 iov = &cmd->iov_data[0];
1083                 iov_count = cmd->iov_data_count;
1084         } else {
1085                 iov = &cmd->iov_misc[0];
1086                 iov_count = cmd->iov_misc_count;
1087         }
1088
1089         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1090         if (tx_size != tx_sent) {
1091                 if (tx_sent == -EAGAIN) {
1092                         pr_err("tx_data() returned -EAGAIN\n");
1093                         goto send_data;
1094                 } else
1095                         return -1;
1096         }
1097         cmd->tx_size = 0;
1098
1099         return 0;
1100 }
1101
1102 int iscsit_fe_sendpage_sg(
1103         struct iscsi_cmd *cmd,
1104         struct iscsi_conn *conn)
1105 {
1106         struct scatterlist *sg = cmd->first_data_sg;
1107         struct kvec iov;
1108         u32 tx_hdr_size, data_len;
1109         u32 offset = cmd->first_data_sg_off;
1110         int tx_sent, iov_off;
1111
1112 send_hdr:
1113         tx_hdr_size = ISCSI_HDR_LEN;
1114         if (conn->conn_ops->HeaderDigest)
1115                 tx_hdr_size += ISCSI_CRC_LEN;
1116
1117         iov.iov_base = cmd->pdu;
1118         iov.iov_len = tx_hdr_size;
1119
1120         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1121         if (tx_hdr_size != tx_sent) {
1122                 if (tx_sent == -EAGAIN) {
1123                         pr_err("tx_data() returned -EAGAIN\n");
1124                         goto send_hdr;
1125                 }
1126                 return -1;
1127         }
1128
1129         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1130         /*
1131          * Set iov_off used by padding and data digest tx_data() calls below
1132          * in order to determine proper offset into cmd->iov_data[]
1133          */
1134         if (conn->conn_ops->DataDigest) {
1135                 data_len -= ISCSI_CRC_LEN;
1136                 if (cmd->padding)
1137                         iov_off = (cmd->iov_data_count - 2);
1138                 else
1139                         iov_off = (cmd->iov_data_count - 1);
1140         } else {
1141                 iov_off = (cmd->iov_data_count - 1);
1142         }
1143         /*
1144          * Perform sendpage() for each page in the scatterlist
1145          */
1146         while (data_len) {
1147                 u32 space = (sg->length - offset);
1148                 u32 sub_len = min_t(u32, data_len, space);
1149 send_pg:
1150                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1151                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1152                 if (tx_sent != sub_len) {
1153                         if (tx_sent == -EAGAIN) {
1154                                 pr_err("tcp_sendpage() returned"
1155                                                 " -EAGAIN\n");
1156                                 goto send_pg;
1157                         }
1158
1159                         pr_err("tcp_sendpage() failure: %d\n",
1160                                         tx_sent);
1161                         return -1;
1162                 }
1163
1164                 data_len -= sub_len;
1165                 offset = 0;
1166                 sg = sg_next(sg);
1167         }
1168
1169 send_padding:
1170         if (cmd->padding) {
1171                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1172
1173                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1174                 if (cmd->padding != tx_sent) {
1175                         if (tx_sent == -EAGAIN) {
1176                                 pr_err("tx_data() returned -EAGAIN\n");
1177                                 goto send_padding;
1178                         }
1179                         return -1;
1180                 }
1181         }
1182
1183 send_datacrc:
1184         if (conn->conn_ops->DataDigest) {
1185                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1186
1187                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1188                 if (ISCSI_CRC_LEN != tx_sent) {
1189                         if (tx_sent == -EAGAIN) {
1190                                 pr_err("tx_data() returned -EAGAIN\n");
1191                                 goto send_datacrc;
1192                         }
1193                         return -1;
1194                 }
1195         }
1196
1197         return 0;
1198 }
1199
1200 /*
1201  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1202  *      back to the Initiator when an expection condition occurs with the
1203  *      errors set in status_class and status_detail.
1204  *
1205  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1206  *      Returns:        0 on success, -1 on error.
1207  */
1208 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1209 {
1210         struct iscsi_login_rsp *hdr;
1211         struct iscsi_login *login = conn->conn_login;
1212
1213         login->login_failed = 1;
1214         iscsit_collect_login_stats(conn, status_class, status_detail);
1215
1216         memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1217
1218         hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1219         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1220         hdr->status_class       = status_class;
1221         hdr->status_detail      = status_detail;
1222         hdr->itt                = conn->login_itt;
1223
1224         return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1225 }
1226
1227 void iscsit_print_session_params(struct iscsi_session *sess)
1228 {
1229         struct iscsi_conn *conn;
1230
1231         pr_debug("-----------------------------[Session Params for"
1232                 " SID: %u]-----------------------------\n", sess->sid);
1233         spin_lock_bh(&sess->conn_lock);
1234         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1235                 iscsi_dump_conn_ops(conn->conn_ops);
1236         spin_unlock_bh(&sess->conn_lock);
1237
1238         iscsi_dump_sess_ops(sess->sess_ops);
1239 }
1240
1241 static int iscsit_do_rx_data(
1242         struct iscsi_conn *conn,
1243         struct iscsi_data_count *count)
1244 {
1245         int data = count->data_length, rx_loop = 0, total_rx = 0;
1246         struct msghdr msg;
1247
1248         if (!conn || !conn->sock || !conn->conn_ops)
1249                 return -1;
1250
1251         memset(&msg, 0, sizeof(struct msghdr));
1252         iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC,
1253                       count->iov, count->iov_count, data);
1254
1255         while (msg_data_left(&msg)) {
1256                 rx_loop = sock_recvmsg(conn->sock, &msg, MSG_WAITALL);
1257                 if (rx_loop <= 0) {
1258                         pr_debug("rx_loop: %d total_rx: %d\n",
1259                                 rx_loop, total_rx);
1260                         return rx_loop;
1261                 }
1262                 total_rx += rx_loop;
1263                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1264                                 rx_loop, total_rx, data);
1265         }
1266
1267         return total_rx;
1268 }
1269
1270 int rx_data(
1271         struct iscsi_conn *conn,
1272         struct kvec *iov,
1273         int iov_count,
1274         int data)
1275 {
1276         struct iscsi_data_count c;
1277
1278         if (!conn || !conn->sock || !conn->conn_ops)
1279                 return -1;
1280
1281         memset(&c, 0, sizeof(struct iscsi_data_count));
1282         c.iov = iov;
1283         c.iov_count = iov_count;
1284         c.data_length = data;
1285         c.type = ISCSI_RX_DATA;
1286
1287         return iscsit_do_rx_data(conn, &c);
1288 }
1289
1290 int tx_data(
1291         struct iscsi_conn *conn,
1292         struct kvec *iov,
1293         int iov_count,
1294         int data)
1295 {
1296         struct msghdr msg;
1297         int total_tx = 0;
1298
1299         if (!conn || !conn->sock || !conn->conn_ops)
1300                 return -1;
1301
1302         if (data <= 0) {
1303                 pr_err("Data length is: %d\n", data);
1304                 return -1;
1305         }
1306
1307         memset(&msg, 0, sizeof(struct msghdr));
1308
1309         iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC,
1310                       iov, iov_count, data);
1311
1312         while (msg_data_left(&msg)) {
1313                 int tx_loop = sock_sendmsg(conn->sock, &msg);
1314                 if (tx_loop <= 0) {
1315                         pr_debug("tx_loop: %d total_tx %d\n",
1316                                 tx_loop, total_tx);
1317                         return tx_loop;
1318                 }
1319                 total_tx += tx_loop;
1320                 pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1321                                         tx_loop, total_tx, data);
1322         }
1323
1324         return total_tx;
1325 }
1326
1327 void iscsit_collect_login_stats(
1328         struct iscsi_conn *conn,
1329         u8 status_class,
1330         u8 status_detail)
1331 {
1332         struct iscsi_param *intrname = NULL;
1333         struct iscsi_tiqn *tiqn;
1334         struct iscsi_login_stats *ls;
1335
1336         tiqn = iscsit_snmp_get_tiqn(conn);
1337         if (!tiqn)
1338                 return;
1339
1340         ls = &tiqn->login_stats;
1341
1342         spin_lock(&ls->lock);
1343         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1344                 ls->accepts++;
1345         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1346                 ls->redirects++;
1347                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1348         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1349                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1350                 ls->authenticate_fails++;
1351                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1352         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1353                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1354                 ls->authorize_fails++;
1355                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1356         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1357                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1358                 ls->negotiate_fails++;
1359                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1360         } else {
1361                 ls->other_fails++;
1362                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1363         }
1364
1365         /* Save initiator name, ip address and time, if it is a failed login */
1366         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1367                 if (conn->param_list)
1368                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1369                                                              conn->param_list);
1370                 strlcpy(ls->last_intr_fail_name,
1371                        (intrname ? intrname->value : "Unknown"),
1372                        sizeof(ls->last_intr_fail_name));
1373
1374                 ls->last_intr_fail_ip_family = conn->login_family;
1375
1376                 ls->last_intr_fail_sockaddr = conn->login_sockaddr;
1377                 ls->last_fail_time = get_jiffies_64();
1378         }
1379
1380         spin_unlock(&ls->lock);
1381 }
1382
1383 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1384 {
1385         struct iscsi_portal_group *tpg;
1386
1387         if (!conn)
1388                 return NULL;
1389
1390         tpg = conn->tpg;
1391         if (!tpg)
1392                 return NULL;
1393
1394         if (!tpg->tpg_tiqn)
1395                 return NULL;
1396
1397         return tpg->tpg_tiqn;
1398 }