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 <scsi/scsi_tcq.h>
  22 #include <scsi/iscsi_proto.h>
  23 #include <target/target_core_base.h>
  24 #include <target/target_core_fabric.h>
  25 #include <target/iscsi/iscsi_transport.h>
  26
  27 #include <target/iscsi/iscsi_target_core.h>
  28 #include "iscsi_target_parameters.h"
  29 #include "iscsi_target_seq_pdu_list.h"
  30 #include "iscsi_target_datain_values.h"
  31 #include "iscsi_target_erl0.h"
  32 #include "iscsi_target_erl1.h"
  33 #include "iscsi_target_erl2.h"
  34 #include "iscsi_target_tpg.h"
  35 #include "iscsi_target_util.h"
  36 #include "iscsi_target.h"
  37
  38 #define PRINT_BUFF(buff, len)                                   \
  39 {                                                               \
  40         int zzz;                                                \
  41                                                                 \
  42         pr_debug("%d:\n", __LINE__);                            \
  43         for (zzz = 0; zzz < len; zzz++) {                       \
  44                 if (zzz % 16 == 0) {                            \
  45                         if (zzz)                                \
  46                                 pr_debug("\n");                 \
  47                         pr_debug("%4i: ", zzz);                 \
  48                 }                                               \
  49                 pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  50         }                                                       \
  51         if ((len + 1) % 16)                                     \
  52                 pr_debug("\n");                                 \
  53 }
  54
  55 extern struct list_head g_tiqn_list;
  56 extern spinlock_t tiqn_lock;
  57
  58 /*
  59  *      Called with cmd->r2t_lock held.
  60  */
  61 int iscsit_add_r2t_to_list(
  62         struct iscsi_cmd *cmd,
  63         u32 offset,
  64         u32 xfer_len,
  65         int recovery,
  66         u32 r2t_sn)
  67 {
  68         struct iscsi_r2t *r2t;
  69
  70         r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  71         if (!r2t) {
  72                 pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  73                 return -1;
  74         }
  75         INIT_LIST_HEAD(&r2t->r2t_list);
  76
  77         r2t->recovery_r2t = recovery;
  78         r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  79         r2t->offset = offset;
  80         r2t->xfer_len = xfer_len;
  81         list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  82         spin_unlock_bh(&cmd->r2t_lock);
  83
  84         iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  85
  86         spin_lock_bh(&cmd->r2t_lock);
  87         return 0;
  88 }
  89
  90 struct iscsi_r2t *iscsit_get_r2t_for_eos(
  91         struct iscsi_cmd *cmd,
  92         u32 offset,
  93         u32 length)
  94 {
  95         struct iscsi_r2t *r2t;
  96
  97         spin_lock_bh(&cmd->r2t_lock);
  98         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
  99                 if ((r2t->offset <= offset) &&
 100                     (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 101                         spin_unlock_bh(&cmd->r2t_lock);
 102                         return r2t;
 103                 }
 104         }
 105         spin_unlock_bh(&cmd->r2t_lock);
 106
 107         pr_err("Unable to locate R2T for Offset: %u, Length:"
 108                         " %u\n", offset, length);
 109         return NULL;
 110 }
 111
 112 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 113 {
 114         struct iscsi_r2t *r2t;
 115
 116         spin_lock_bh(&cmd->r2t_lock);
 117         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 118                 if (!r2t->sent_r2t) {
 119                         spin_unlock_bh(&cmd->r2t_lock);
 120                         return r2t;
 121                 }
 122         }
 123         spin_unlock_bh(&cmd->r2t_lock);
 124
 125         pr_err("Unable to locate next R2T to send for ITT:"
 126                         " 0x%08x.\n", cmd->init_task_tag);
 127         return NULL;
 128 }
 129
 130 /*
 131  *      Called with cmd->r2t_lock held.
 132  */
 133 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 134 {
 135         list_del(&r2t->r2t_list);
 136         kmem_cache_free(lio_r2t_cache, r2t);
 137 }
 138
 139 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 140 {
 141         struct iscsi_r2t *r2t, *r2t_tmp;
 142
 143         spin_lock_bh(&cmd->r2t_lock);
 144         list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 145                 iscsit_free_r2t(r2t, cmd);
 146         spin_unlock_bh(&cmd->r2t_lock);
 147 }
 148
 149 /*
 150  * May be called from software interrupt (timer) context for allocating
 151  * iSCSI NopINs.
 152  */
 153 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, int state)
 154 {
 155         struct iscsi_cmd *cmd;
 156         struct se_session *se_sess = conn->sess->se_sess;
 157         int size, tag;
 158
 159         tag = percpu_ida_alloc(&se_sess->sess_tag_pool, state);
 160         if (tag < 0)
 161                 return NULL;
 162
 163         size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
 164         cmd = (struct iscsi_cmd *)(se_sess->sess_cmd_map + (tag * size));
 165         memset(cmd, 0, size);
 166
 167         cmd->se_cmd.map_tag = tag;
 168         cmd->conn = conn;
 169         INIT_LIST_HEAD(&cmd->i_conn_node);
 170         INIT_LIST_HEAD(&cmd->datain_list);
 171         INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 172         spin_lock_init(&cmd->datain_lock);
 173         spin_lock_init(&cmd->dataout_timeout_lock);
 174         spin_lock_init(&cmd->istate_lock);
 175         spin_lock_init(&cmd->error_lock);
 176         spin_lock_init(&cmd->r2t_lock);
 177
 178         return cmd;
 179 }
 180 EXPORT_SYMBOL(iscsit_allocate_cmd);
 181
 182 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 183         struct iscsi_cmd *cmd,
 184         u32 seq_send_order)
 185 {
 186         u32 i;
 187
 188         for (i = 0; i < cmd->seq_count; i++)
 189                 if (cmd->seq_list[i].seq_send_order == seq_send_order)
 190                         return &cmd->seq_list[i];
 191
 192         return NULL;
 193 }
 194
 195 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 196 {
 197         u32 i;
 198
 199         if (!cmd->seq_list) {
 200                 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 201                 return NULL;
 202         }
 203
 204         for (i = 0; i < cmd->seq_count; i++) {
 205                 if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 206                         continue;
 207                 if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 208                         cmd->seq_send_order++;
 209                         return &cmd->seq_list[i];
 210                 }
 211         }
 212
 213         return NULL;
 214 }
 215
 216 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 217         struct iscsi_cmd *cmd,
 218         u32 r2t_sn)
 219 {
 220         struct iscsi_r2t *r2t;
 221
 222         spin_lock_bh(&cmd->r2t_lock);
 223         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 224                 if (r2t->r2t_sn == r2t_sn) {
 225                         spin_unlock_bh(&cmd->r2t_lock);
 226                         return r2t;
 227                 }
 228         }
 229         spin_unlock_bh(&cmd->r2t_lock);
 230
 231         return NULL;
 232 }
 233
 234 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 235 {
 236         u32 max_cmdsn;
 237         int ret;
 238
 239         /*
 240          * This is the proper method of checking received CmdSN against
 241          * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 242          * or order CmdSNs due to multiple connection sessions and/or
 243          * CRC failures.
 244          */
 245         max_cmdsn = atomic_read(&sess->max_cmd_sn);
 246         if (iscsi_sna_gt(cmdsn, max_cmdsn)) {
 247                 pr_err("Received CmdSN: 0x%08x is greater than"
 248                        " MaxCmdSN: 0x%08x, ignoring.\n", cmdsn, max_cmdsn);
 249                 ret = CMDSN_MAXCMDSN_OVERRUN;
 250
 251         } else if (cmdsn == sess->exp_cmd_sn) {
 252                 sess->exp_cmd_sn++;
 253                 pr_debug("Received CmdSN matches ExpCmdSN,"
 254                       " incremented ExpCmdSN to: 0x%08x\n",
 255                       sess->exp_cmd_sn);
 256                 ret = CMDSN_NORMAL_OPERATION;
 257
 258         } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 259                 pr_debug("Received CmdSN: 0x%08x is greater"
 260                       " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 261                       cmdsn, sess->exp_cmd_sn);
 262                 ret = CMDSN_HIGHER_THAN_EXP;
 263
 264         } else {
 265                 pr_err("Received CmdSN: 0x%08x is less than"
 266                        " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 267                        sess->exp_cmd_sn);
 268                 ret = CMDSN_LOWER_THAN_EXP;
 269         }
 270
 271         return ret;
 272 }
 273
 274 /*
 275  * Commands may be received out of order if MC/S is in use.
 276  * Ensure they are executed in CmdSN order.
 277  */
 278 int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 279                         unsigned char *buf, __be32 cmdsn)
 280 {
 281         int ret, cmdsn_ret;
 282         bool reject = false;
 283         u8 reason = ISCSI_REASON_BOOKMARK_NO_RESOURCES;
 284
 285         mutex_lock(&conn->sess->cmdsn_mutex);
 286
 287         cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
 288         switch (cmdsn_ret) {
 289         case CMDSN_NORMAL_OPERATION:
 290                 ret = iscsit_execute_cmd(cmd, 0);
 291                 if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 292                         iscsit_execute_ooo_cmdsns(conn->sess);
 293                 else if (ret < 0) {
 294                         reject = true;
 295                         ret = CMDSN_ERROR_CANNOT_RECOVER;
 296                 }
 297                 break;
 298         case CMDSN_HIGHER_THAN_EXP:
 299                 ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
 300                 if (ret < 0) {
 301                         reject = true;
 302                         ret = CMDSN_ERROR_CANNOT_RECOVER;
 303                         break;
 304                 }
 305                 ret = CMDSN_HIGHER_THAN_EXP;
 306                 break;
 307         case CMDSN_LOWER_THAN_EXP:
 308         case CMDSN_MAXCMDSN_OVERRUN:
 309         default:
 310                 cmd->i_state = ISTATE_REMOVE;
 311                 iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 312                 /*
 313                  * Existing callers for iscsit_sequence_cmd() will silently
 314                  * ignore commands with CMDSN_LOWER_THAN_EXP, so force this
 315                  * return for CMDSN_MAXCMDSN_OVERRUN as well..
 316                  */
 317                 ret = CMDSN_LOWER_THAN_EXP;
 318                 break;
 319         }
 320         mutex_unlock(&conn->sess->cmdsn_mutex);
 321
 322         if (reject)
 323                 iscsit_reject_cmd(cmd, reason, buf);
 324
 325         return ret;
 326 }
 327 EXPORT_SYMBOL(iscsit_sequence_cmd);
 328
 329 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 330 {
 331         struct iscsi_conn *conn = cmd->conn;
 332         struct se_cmd *se_cmd = &cmd->se_cmd;
 333         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 334         u32 payload_length = ntoh24(hdr->dlength);
 335
 336         if (conn->sess->sess_ops->InitialR2T) {
 337                 pr_err("Received unexpected unsolicited data"
 338                         " while InitialR2T=Yes, protocol error.\n");
 339                 transport_send_check_condition_and_sense(se_cmd,
 340                                 TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 341                 return -1;
 342         }
 343
 344         if ((cmd->first_burst_len + payload_length) >
 345              conn->sess->sess_ops->FirstBurstLength) {
 346                 pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 347                         " for this Unsolicited DataOut Burst.\n",
 348                         (cmd->first_burst_len + payload_length),
 349                                 conn->sess->sess_ops->FirstBurstLength);
 350                 transport_send_check_condition_and_sense(se_cmd,
 351                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 352                 return -1;
 353         }
 354
 355         if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 356                 return 0;
 357
 358         if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 359             ((cmd->first_burst_len + payload_length) !=
 360               conn->sess->sess_ops->FirstBurstLength)) {
 361                 pr_err("Unsolicited non-immediate data received %u"
 362                         " does not equal FirstBurstLength: %u, and does"
 363                         " not equal ExpXferLen %u.\n",
 364                         (cmd->first_burst_len + payload_length),
 365                         conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 366                 transport_send_check_condition_and_sense(se_cmd,
 367                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 368                 return -1;
 369         }
 370         return 0;
 371 }
 372
 373 struct iscsi_cmd *iscsit_find_cmd_from_itt(
 374         struct iscsi_conn *conn,
 375         itt_t init_task_tag)
 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                         init_task_tag, conn->cid);
 390         return NULL;
 391 }
 392 EXPORT_SYMBOL(iscsit_find_cmd_from_itt);
 393
 394 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 395         struct iscsi_conn *conn,
 396         itt_t init_task_tag,
 397         u32 length)
 398 {
 399         struct iscsi_cmd *cmd;
 400
 401         spin_lock_bh(&conn->cmd_lock);
 402         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 403                 if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT)
 404                         continue;
 405                 if (cmd->init_task_tag == init_task_tag) {
 406                         spin_unlock_bh(&conn->cmd_lock);
 407                         return cmd;
 408                 }
 409         }
 410         spin_unlock_bh(&conn->cmd_lock);
 411
 412         pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 413                         " dumping payload\n", init_task_tag, conn->cid);
 414         if (length)
 415                 iscsit_dump_data_payload(conn, length, 1);
 416
 417         return NULL;
 418 }
 419
 420 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 421         struct iscsi_conn *conn,
 422         u32 targ_xfer_tag)
 423 {
 424         struct iscsi_cmd *cmd = NULL;
 425
 426         spin_lock_bh(&conn->cmd_lock);
 427         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 428                 if (cmd->targ_xfer_tag == targ_xfer_tag) {
 429                         spin_unlock_bh(&conn->cmd_lock);
 430                         return cmd;
 431                 }
 432         }
 433         spin_unlock_bh(&conn->cmd_lock);
 434
 435         pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 436                         targ_xfer_tag, conn->cid);
 437         return NULL;
 438 }
 439
 440 int iscsit_find_cmd_for_recovery(
 441         struct iscsi_session *sess,
 442         struct iscsi_cmd **cmd_ptr,
 443         struct iscsi_conn_recovery **cr_ptr,
 444         itt_t init_task_tag)
 445 {
 446         struct iscsi_cmd *cmd = NULL;
 447         struct iscsi_conn_recovery *cr;
 448         /*
 449          * Scan through the inactive connection recovery list's command list.
 450          * If init_task_tag matches the command is still alligent.
 451          */
 452         spin_lock(&sess->cr_i_lock);
 453         list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 454                 spin_lock(&cr->conn_recovery_cmd_lock);
 455                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 456                         if (cmd->init_task_tag == init_task_tag) {
 457                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 458                                 spin_unlock(&sess->cr_i_lock);
 459
 460                                 *cr_ptr = cr;
 461                                 *cmd_ptr = cmd;
 462                                 return -2;
 463                         }
 464                 }
 465                 spin_unlock(&cr->conn_recovery_cmd_lock);
 466         }
 467         spin_unlock(&sess->cr_i_lock);
 468         /*
 469          * Scan through the active connection recovery list's command list.
 470          * If init_task_tag matches the command is ready to be reassigned.
 471          */
 472         spin_lock(&sess->cr_a_lock);
 473         list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 474                 spin_lock(&cr->conn_recovery_cmd_lock);
 475                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 476                         if (cmd->init_task_tag == init_task_tag) {
 477                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 478                                 spin_unlock(&sess->cr_a_lock);
 479
 480                                 *cr_ptr = cr;
 481                                 *cmd_ptr = cmd;
 482                                 return 0;
 483                         }
 484                 }
 485                 spin_unlock(&cr->conn_recovery_cmd_lock);
 486         }
 487         spin_unlock(&sess->cr_a_lock);
 488
 489         return -1;
 490 }
 491
 492 void iscsit_add_cmd_to_immediate_queue(
 493         struct iscsi_cmd *cmd,
 494         struct iscsi_conn *conn,
 495         u8 state)
 496 {
 497         struct iscsi_queue_req *qr;
 498
 499         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 500         if (!qr) {
 501                 pr_err("Unable to allocate memory for"
 502                                 " struct iscsi_queue_req\n");
 503                 return;
 504         }
 505         INIT_LIST_HEAD(&qr->qr_list);
 506         qr->cmd = cmd;
 507         qr->state = state;
 508
 509         spin_lock_bh(&conn->immed_queue_lock);
 510         list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 511         atomic_inc(&cmd->immed_queue_count);
 512         atomic_set(&conn->check_immediate_queue, 1);
 513         spin_unlock_bh(&conn->immed_queue_lock);
 514
 515         wake_up(&conn->queues_wq);
 516 }
 517 EXPORT_SYMBOL(iscsit_add_cmd_to_immediate_queue);
 518
 519 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 520 {
 521         struct iscsi_queue_req *qr;
 522
 523         spin_lock_bh(&conn->immed_queue_lock);
 524         if (list_empty(&conn->immed_queue_list)) {
 525                 spin_unlock_bh(&conn->immed_queue_lock);
 526                 return NULL;
 527         }
 528         qr = list_first_entry(&conn->immed_queue_list,
 529                               struct iscsi_queue_req, qr_list);
 530
 531         list_del(&qr->qr_list);
 532         if (qr->cmd)
 533                 atomic_dec(&qr->cmd->immed_queue_count);
 534         spin_unlock_bh(&conn->immed_queue_lock);
 535
 536         return qr;
 537 }
 538
 539 static void iscsit_remove_cmd_from_immediate_queue(
 540         struct iscsi_cmd *cmd,
 541         struct iscsi_conn *conn)
 542 {
 543         struct iscsi_queue_req *qr, *qr_tmp;
 544
 545         spin_lock_bh(&conn->immed_queue_lock);
 546         if (!atomic_read(&cmd->immed_queue_count)) {
 547                 spin_unlock_bh(&conn->immed_queue_lock);
 548                 return;
 549         }
 550
 551         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 552                 if (qr->cmd != cmd)
 553                         continue;
 554
 555                 atomic_dec(&qr->cmd->immed_queue_count);
 556                 list_del(&qr->qr_list);
 557                 kmem_cache_free(lio_qr_cache, qr);
 558         }
 559         spin_unlock_bh(&conn->immed_queue_lock);
 560
 561         if (atomic_read(&cmd->immed_queue_count)) {
 562                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 563                         cmd->init_task_tag,
 564                         atomic_read(&cmd->immed_queue_count));
 565         }
 566 }
 567
 568 void iscsit_add_cmd_to_response_queue(
 569         struct iscsi_cmd *cmd,
 570         struct iscsi_conn *conn,
 571         u8 state)
 572 {
 573         struct iscsi_queue_req *qr;
 574
 575         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 576         if (!qr) {
 577                 pr_err("Unable to allocate memory for"
 578                         " struct iscsi_queue_req\n");
 579                 return;
 580         }
 581         INIT_LIST_HEAD(&qr->qr_list);
 582         qr->cmd = cmd;
 583         qr->state = state;
 584
 585         spin_lock_bh(&conn->response_queue_lock);
 586         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 587         atomic_inc(&cmd->response_queue_count);
 588         spin_unlock_bh(&conn->response_queue_lock);
 589
 590         wake_up(&conn->queues_wq);
 591 }
 592
 593 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 594 {
 595         struct iscsi_queue_req *qr;
 596
 597         spin_lock_bh(&conn->response_queue_lock);
 598         if (list_empty(&conn->response_queue_list)) {
 599                 spin_unlock_bh(&conn->response_queue_lock);
 600                 return NULL;
 601         }
 602
 603         qr = list_first_entry(&conn->response_queue_list,
 604                               struct iscsi_queue_req, qr_list);
 605
 606         list_del(&qr->qr_list);
 607         if (qr->cmd)
 608                 atomic_dec(&qr->cmd->response_queue_count);
 609         spin_unlock_bh(&conn->response_queue_lock);
 610
 611         return qr;
 612 }
 613
 614 static void iscsit_remove_cmd_from_response_queue(
 615         struct iscsi_cmd *cmd,
 616         struct iscsi_conn *conn)
 617 {
 618         struct iscsi_queue_req *qr, *qr_tmp;
 619
 620         spin_lock_bh(&conn->response_queue_lock);
 621         if (!atomic_read(&cmd->response_queue_count)) {
 622                 spin_unlock_bh(&conn->response_queue_lock);
 623                 return;
 624         }
 625
 626         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 627                                 qr_list) {
 628                 if (qr->cmd != cmd)
 629                         continue;
 630
 631                 atomic_dec(&qr->cmd->response_queue_count);
 632                 list_del(&qr->qr_list);
 633                 kmem_cache_free(lio_qr_cache, qr);
 634         }
 635         spin_unlock_bh(&conn->response_queue_lock);
 636
 637         if (atomic_read(&cmd->response_queue_count)) {
 638                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 639                         cmd->init_task_tag,
 640                         atomic_read(&cmd->response_queue_count));
 641         }
 642 }
 643
 644 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 645 {
 646         bool empty;
 647
 648         spin_lock_bh(&conn->immed_queue_lock);
 649         empty = list_empty(&conn->immed_queue_list);
 650         spin_unlock_bh(&conn->immed_queue_lock);
 651
 652         if (!empty)
 653                 return empty;
 654
 655         spin_lock_bh(&conn->response_queue_lock);
 656         empty = list_empty(&conn->response_queue_list);
 657         spin_unlock_bh(&conn->response_queue_lock);
 658
 659         return empty;
 660 }
 661
 662 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 663 {
 664         struct iscsi_queue_req *qr, *qr_tmp;
 665
 666         spin_lock_bh(&conn->immed_queue_lock);
 667         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 668                 list_del(&qr->qr_list);
 669                 if (qr->cmd)
 670                         atomic_dec(&qr->cmd->immed_queue_count);
 671
 672                 kmem_cache_free(lio_qr_cache, qr);
 673         }
 674         spin_unlock_bh(&conn->immed_queue_lock);
 675
 676         spin_lock_bh(&conn->response_queue_lock);
 677         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 678                         qr_list) {
 679                 list_del(&qr->qr_list);
 680                 if (qr->cmd)
 681                         atomic_dec(&qr->cmd->response_queue_count);
 682
 683                 kmem_cache_free(lio_qr_cache, qr);
 684         }
 685         spin_unlock_bh(&conn->response_queue_lock);
 686 }
 687
 688 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 689 {
 690         struct iscsi_session *sess;
 691         struct se_cmd *se_cmd = &cmd->se_cmd;
 692
 693         if (cmd->conn)
 694                 sess = cmd->conn->sess;
 695         else
 696                 sess = cmd->sess;
 697
 698         BUG_ON(!sess || !sess->se_sess);
 699
 700         kfree(cmd->buf_ptr);
 701         kfree(cmd->pdu_list);
 702         kfree(cmd->seq_list);
 703         kfree(cmd->tmr_req);
 704         kfree(cmd->iov_data);
 705         kfree(cmd->text_in_ptr);
 706
 707         percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 708 }
 709 EXPORT_SYMBOL(iscsit_release_cmd);
 710
 711 void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool scsi_cmd,
 712                        bool check_queues)
 713 {
 714         struct iscsi_conn *conn = cmd->conn;
 715
 716         if (scsi_cmd) {
 717                 if (cmd->data_direction == DMA_TO_DEVICE) {
 718                         iscsit_stop_dataout_timer(cmd);
 719                         iscsit_free_r2ts_from_list(cmd);
 720                 }
 721                 if (cmd->data_direction == DMA_FROM_DEVICE)
 722                         iscsit_free_all_datain_reqs(cmd);
 723         }
 724
 725         if (conn && check_queues) {
 726                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 727                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 728         }
 729
 730         if (conn && conn->conn_transport->iscsit_release_cmd)
 731                 conn->conn_transport->iscsit_release_cmd(conn, cmd);
 732 }
 733
 734 void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 735 {
 736         struct se_cmd *se_cmd = NULL;
 737         int rc;
 738         /*
 739          * Determine if a struct se_cmd is associated with
 740          * this struct iscsi_cmd.
 741          */
 742         switch (cmd->iscsi_opcode) {
 743         case ISCSI_OP_SCSI_CMD:
 744                 se_cmd = &cmd->se_cmd;
 745                 __iscsit_free_cmd(cmd, true, shutdown);
 746                 /*
 747                  * Fallthrough
 748                  */
 749         case ISCSI_OP_SCSI_TMFUNC:
 750                 rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 751                 if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
 752                         __iscsit_free_cmd(cmd, true, shutdown);
 753                         target_put_sess_cmd(se_cmd);
 754                 }
 755                 break;
 756         case ISCSI_OP_REJECT:
 757                 /*
 758                  * Handle special case for REJECT when iscsi_add_reject*() has
 759                  * overwritten the original iscsi_opcode assignment, and the
 760                  * associated cmd->se_cmd needs to be released.
 761                  */
 762                 if (cmd->se_cmd.se_tfo != NULL) {
 763                         se_cmd = &cmd->se_cmd;
 764                         __iscsit_free_cmd(cmd, true, shutdown);
 765
 766                         rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 767                         if (!rc && shutdown && se_cmd->se_sess) {
 768                                 __iscsit_free_cmd(cmd, true, shutdown);
 769                                 target_put_sess_cmd(se_cmd);
 770                         }
 771                         break;
 772                 }
 773                 /* Fall-through */
 774         default:
 775                 __iscsit_free_cmd(cmd, false, shutdown);
 776                 iscsit_release_cmd(cmd);
 777                 break;
 778         }
 779 }
 780 EXPORT_SYMBOL(iscsit_free_cmd);
 781
 782 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 783 {
 784         spin_lock_bh(&sess->session_usage_lock);
 785         if (sess->session_usage_count != 0) {
 786                 sess->session_waiting_on_uc = 1;
 787                 spin_unlock_bh(&sess->session_usage_lock);
 788                 if (in_interrupt())
 789                         return 2;
 790
 791                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 792                 return 1;
 793         }
 794         spin_unlock_bh(&sess->session_usage_lock);
 795
 796         return 0;
 797 }
 798
 799 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 800 {
 801         spin_lock_bh(&sess->session_usage_lock);
 802         sess->session_usage_count--;
 803
 804         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 805                 complete(&sess->session_waiting_on_uc_comp);
 806
 807         spin_unlock_bh(&sess->session_usage_lock);
 808 }
 809
 810 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 811 {
 812         spin_lock_bh(&sess->session_usage_lock);
 813         sess->session_usage_count++;
 814         spin_unlock_bh(&sess->session_usage_lock);
 815 }
 816
 817 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 818 {
 819         struct iscsi_conn *conn;
 820
 821         spin_lock_bh(&sess->conn_lock);
 822         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 823                 if ((conn->cid == cid) &&
 824                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 825                         iscsit_inc_conn_usage_count(conn);
 826                         spin_unlock_bh(&sess->conn_lock);
 827                         return conn;
 828                 }
 829         }
 830         spin_unlock_bh(&sess->conn_lock);
 831
 832         return NULL;
 833 }
 834
 835 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 836 {
 837         struct iscsi_conn *conn;
 838
 839         spin_lock_bh(&sess->conn_lock);
 840         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 841                 if (conn->cid == cid) {
 842                         iscsit_inc_conn_usage_count(conn);
 843                         spin_lock(&conn->state_lock);
 844                         atomic_set(&conn->connection_wait_rcfr, 1);
 845                         spin_unlock(&conn->state_lock);
 846                         spin_unlock_bh(&sess->conn_lock);
 847                         return conn;
 848                 }
 849         }
 850         spin_unlock_bh(&sess->conn_lock);
 851
 852         return NULL;
 853 }
 854
 855 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 856 {
 857         spin_lock_bh(&conn->conn_usage_lock);
 858         if (conn->conn_usage_count != 0) {
 859                 conn->conn_waiting_on_uc = 1;
 860                 spin_unlock_bh(&conn->conn_usage_lock);
 861
 862                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 863                 return;
 864         }
 865         spin_unlock_bh(&conn->conn_usage_lock);
 866 }
 867
 868 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 869 {
 870         spin_lock_bh(&conn->conn_usage_lock);
 871         conn->conn_usage_count--;
 872
 873         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 874                 complete(&conn->conn_waiting_on_uc_comp);
 875
 876         spin_unlock_bh(&conn->conn_usage_lock);
 877 }
 878
 879 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 880 {
 881         spin_lock_bh(&conn->conn_usage_lock);
 882         conn->conn_usage_count++;
 883         spin_unlock_bh(&conn->conn_usage_lock);
 884 }
 885
 886 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 887 {
 888         u8 state;
 889         struct iscsi_cmd *cmd;
 890
 891         cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
 892         if (!cmd)
 893                 return -1;
 894
 895         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 896         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 897                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 898         cmd->init_task_tag = RESERVED_ITT;
 899         cmd->targ_xfer_tag = (want_response) ?
 900                              session_get_next_ttt(conn->sess) : 0xFFFFFFFF;
 901         spin_lock_bh(&conn->cmd_lock);
 902         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 903         spin_unlock_bh(&conn->cmd_lock);
 904
 905         if (want_response)
 906                 iscsit_start_nopin_response_timer(conn);
 907         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 908
 909         return 0;
 910 }
 911
 912 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 913 {
 914         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 915
 916         iscsit_inc_conn_usage_count(conn);
 917
 918         spin_lock_bh(&conn->nopin_timer_lock);
 919         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 920                 spin_unlock_bh(&conn->nopin_timer_lock);
 921                 iscsit_dec_conn_usage_count(conn);
 922                 return;
 923         }
 924
 925         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 926                 " SID: %u, failing connection.\n", conn->cid,
 927                         conn->sess->sid);
 928         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 929         spin_unlock_bh(&conn->nopin_timer_lock);
 930
 931         {
 932         struct iscsi_portal_group *tpg = conn->sess->tpg;
 933         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 934
 935         if (tiqn) {
 936                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 937                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 938                                 conn->sess->sess_ops->InitiatorName);
 939                 tiqn->sess_err_stats.last_sess_failure_type =
 940                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 941                 tiqn->sess_err_stats.cxn_timeout_errors++;
 942                 atomic_long_inc(&conn->sess->conn_timeout_errors);
 943                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 944         }
 945         }
 946
 947         iscsit_cause_connection_reinstatement(conn, 0);
 948         iscsit_dec_conn_usage_count(conn);
 949 }
 950
 951 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 952 {
 953         struct iscsi_session *sess = conn->sess;
 954         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 955
 956         spin_lock_bh(&conn->nopin_timer_lock);
 957         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 958                 spin_unlock_bh(&conn->nopin_timer_lock);
 959                 return;
 960         }
 961
 962         mod_timer(&conn->nopin_response_timer,
 963                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
 964         spin_unlock_bh(&conn->nopin_timer_lock);
 965 }
 966
 967 /*
 968  *      Called with conn->nopin_timer_lock held.
 969  */
 970 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
 971 {
 972         struct iscsi_session *sess = conn->sess;
 973         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 974
 975         spin_lock_bh(&conn->nopin_timer_lock);
 976         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
 977                 spin_unlock_bh(&conn->nopin_timer_lock);
 978                 return;
 979         }
 980
 981         init_timer(&conn->nopin_response_timer);
 982         conn->nopin_response_timer.expires =
 983                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
 984         conn->nopin_response_timer.data = (unsigned long)conn;
 985         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
 986         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
 987         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
 988         add_timer(&conn->nopin_response_timer);
 989
 990         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
 991                 " seconds\n", conn->cid, na->nopin_response_timeout);
 992         spin_unlock_bh(&conn->nopin_timer_lock);
 993 }
 994
 995 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
 996 {
 997         spin_lock_bh(&conn->nopin_timer_lock);
 998         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 999                 spin_unlock_bh(&conn->nopin_timer_lock);
1000                 return;
1001         }
1002         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1003         spin_unlock_bh(&conn->nopin_timer_lock);
1004
1005         del_timer_sync(&conn->nopin_response_timer);
1006
1007         spin_lock_bh(&conn->nopin_timer_lock);
1008         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1009         spin_unlock_bh(&conn->nopin_timer_lock);
1010 }
1011
1012 static void iscsit_handle_nopin_timeout(unsigned long data)
1013 {
1014         struct iscsi_conn *conn = (struct iscsi_conn *) data;
1015
1016         iscsit_inc_conn_usage_count(conn);
1017
1018         spin_lock_bh(&conn->nopin_timer_lock);
1019         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1020                 spin_unlock_bh(&conn->nopin_timer_lock);
1021                 iscsit_dec_conn_usage_count(conn);
1022                 return;
1023         }
1024         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1025         spin_unlock_bh(&conn->nopin_timer_lock);
1026
1027         iscsit_add_nopin(conn, 1);
1028         iscsit_dec_conn_usage_count(conn);
1029 }
1030
1031 /*
1032  * Called with conn->nopin_timer_lock held.
1033  */
1034 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1035 {
1036         struct iscsi_session *sess = conn->sess;
1037         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1038         /*
1039         * NOPIN timeout is disabled.
1040          */
1041         if (!na->nopin_timeout)
1042                 return;
1043
1044         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1045                 return;
1046
1047         init_timer(&conn->nopin_timer);
1048         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1049         conn->nopin_timer.data = (unsigned long)conn;
1050         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1051         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1052         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1053         add_timer(&conn->nopin_timer);
1054
1055         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1056                 " interval\n", conn->cid, na->nopin_timeout);
1057 }
1058
1059 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1060 {
1061         struct iscsi_session *sess = conn->sess;
1062         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1063         /*
1064          * NOPIN timeout is disabled..
1065          */
1066         if (!na->nopin_timeout)
1067                 return;
1068
1069         spin_lock_bh(&conn->nopin_timer_lock);
1070         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1071                 spin_unlock_bh(&conn->nopin_timer_lock);
1072                 return;
1073         }
1074
1075         init_timer(&conn->nopin_timer);
1076         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1077         conn->nopin_timer.data = (unsigned long)conn;
1078         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1079         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1080         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1081         add_timer(&conn->nopin_timer);
1082
1083         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1084                         " interval\n", conn->cid, na->nopin_timeout);
1085         spin_unlock_bh(&conn->nopin_timer_lock);
1086 }
1087
1088 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1089 {
1090         spin_lock_bh(&conn->nopin_timer_lock);
1091         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1092                 spin_unlock_bh(&conn->nopin_timer_lock);
1093                 return;
1094         }
1095         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1096         spin_unlock_bh(&conn->nopin_timer_lock);
1097
1098         del_timer_sync(&conn->nopin_timer);
1099
1100         spin_lock_bh(&conn->nopin_timer_lock);
1101         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1102         spin_unlock_bh(&conn->nopin_timer_lock);
1103 }
1104
1105 int iscsit_send_tx_data(
1106         struct iscsi_cmd *cmd,
1107         struct iscsi_conn *conn,
1108         int use_misc)
1109 {
1110         int tx_sent, tx_size;
1111         u32 iov_count;
1112         struct kvec *iov;
1113
1114 send_data:
1115         tx_size = cmd->tx_size;
1116
1117         if (!use_misc) {
1118                 iov = &cmd->iov_data[0];
1119                 iov_count = cmd->iov_data_count;
1120         } else {
1121                 iov = &cmd->iov_misc[0];
1122                 iov_count = cmd->iov_misc_count;
1123         }
1124
1125         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1126         if (tx_size != tx_sent) {
1127                 if (tx_sent == -EAGAIN) {
1128                         pr_err("tx_data() returned -EAGAIN\n");
1129                         goto send_data;
1130                 } else
1131                         return -1;
1132         }
1133         cmd->tx_size = 0;
1134
1135         return 0;
1136 }
1137
1138 int iscsit_fe_sendpage_sg(
1139         struct iscsi_cmd *cmd,
1140         struct iscsi_conn *conn)
1141 {
1142         struct scatterlist *sg = cmd->first_data_sg;
1143         struct kvec iov;
1144         u32 tx_hdr_size, data_len;
1145         u32 offset = cmd->first_data_sg_off;
1146         int tx_sent, iov_off;
1147
1148 send_hdr:
1149         tx_hdr_size = ISCSI_HDR_LEN;
1150         if (conn->conn_ops->HeaderDigest)
1151                 tx_hdr_size += ISCSI_CRC_LEN;
1152
1153         iov.iov_base = cmd->pdu;
1154         iov.iov_len = tx_hdr_size;
1155
1156         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1157         if (tx_hdr_size != tx_sent) {
1158                 if (tx_sent == -EAGAIN) {
1159                         pr_err("tx_data() returned -EAGAIN\n");
1160                         goto send_hdr;
1161                 }
1162                 return -1;
1163         }
1164
1165         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1166         /*
1167          * Set iov_off used by padding and data digest tx_data() calls below
1168          * in order to determine proper offset into cmd->iov_data[]
1169          */
1170         if (conn->conn_ops->DataDigest) {
1171                 data_len -= ISCSI_CRC_LEN;
1172                 if (cmd->padding)
1173                         iov_off = (cmd->iov_data_count - 2);
1174                 else
1175                         iov_off = (cmd->iov_data_count - 1);
1176         } else {
1177                 iov_off = (cmd->iov_data_count - 1);
1178         }
1179         /*
1180          * Perform sendpage() for each page in the scatterlist
1181          */
1182         while (data_len) {
1183                 u32 space = (sg->length - offset);
1184                 u32 sub_len = min_t(u32, data_len, space);
1185 send_pg:
1186                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1187                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1188                 if (tx_sent != sub_len) {
1189                         if (tx_sent == -EAGAIN) {
1190                                 pr_err("tcp_sendpage() returned"
1191                                                 " -EAGAIN\n");
1192                                 goto send_pg;
1193                         }
1194
1195                         pr_err("tcp_sendpage() failure: %d\n",
1196                                         tx_sent);
1197                         return -1;
1198                 }
1199
1200                 data_len -= sub_len;
1201                 offset = 0;
1202                 sg = sg_next(sg);
1203         }
1204
1205 send_padding:
1206         if (cmd->padding) {
1207                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1208
1209                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1210                 if (cmd->padding != tx_sent) {
1211                         if (tx_sent == -EAGAIN) {
1212                                 pr_err("tx_data() returned -EAGAIN\n");
1213                                 goto send_padding;
1214                         }
1215                         return -1;
1216                 }
1217         }
1218
1219 send_datacrc:
1220         if (conn->conn_ops->DataDigest) {
1221                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1222
1223                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1224                 if (ISCSI_CRC_LEN != tx_sent) {
1225                         if (tx_sent == -EAGAIN) {
1226                                 pr_err("tx_data() returned -EAGAIN\n");
1227                                 goto send_datacrc;
1228                         }
1229                         return -1;
1230                 }
1231         }
1232
1233         return 0;
1234 }
1235
1236 /*
1237  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1238  *      back to the Initiator when an expection condition occurs with the
1239  *      errors set in status_class and status_detail.
1240  *
1241  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1242  *      Returns:        0 on success, -1 on error.
1243  */
1244 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1245 {
1246         struct iscsi_login_rsp *hdr;
1247         struct iscsi_login *login = conn->conn_login;
1248
1249         login->login_failed = 1;
1250         iscsit_collect_login_stats(conn, status_class, status_detail);
1251
1252         memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1253
1254         hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1255         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1256         hdr->status_class       = status_class;
1257         hdr->status_detail      = status_detail;
1258         hdr->itt                = conn->login_itt;
1259
1260         return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1261 }
1262
1263 void iscsit_print_session_params(struct iscsi_session *sess)
1264 {
1265         struct iscsi_conn *conn;
1266
1267         pr_debug("-----------------------------[Session Params for"
1268                 " SID: %u]-----------------------------\n", sess->sid);
1269         spin_lock_bh(&sess->conn_lock);
1270         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1271                 iscsi_dump_conn_ops(conn->conn_ops);
1272         spin_unlock_bh(&sess->conn_lock);
1273
1274         iscsi_dump_sess_ops(sess->sess_ops);
1275 }
1276
1277 static int iscsit_do_rx_data(
1278         struct iscsi_conn *conn,
1279         struct iscsi_data_count *count)
1280 {
1281         int data = count->data_length, rx_loop = 0, total_rx = 0;
1282         struct msghdr msg;
1283
1284         if (!conn || !conn->sock || !conn->conn_ops)
1285                 return -1;
1286
1287         memset(&msg, 0, sizeof(struct msghdr));
1288         iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC,
1289                       count->iov, count->iov_count, data);
1290
1291         while (msg_data_left(&msg)) {
1292                 rx_loop = sock_recvmsg(conn->sock, &msg, MSG_WAITALL);
1293                 if (rx_loop <= 0) {
1294                         pr_debug("rx_loop: %d total_rx: %d\n",
1295                                 rx_loop, total_rx);
1296                         return rx_loop;
1297                 }
1298                 total_rx += rx_loop;
1299                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1300                                 rx_loop, total_rx, data);
1301         }
1302
1303         return total_rx;
1304 }
1305
1306 static int iscsit_do_tx_data(
1307         struct iscsi_conn *conn,
1308         struct iscsi_data_count *count)
1309 {
1310         int ret, iov_len;
1311         struct kvec *iov_p;
1312         struct msghdr msg;
1313
1314         if (!conn || !conn->sock || !conn->conn_ops)
1315                 return -1;
1316
1317         if (count->data_length <= 0) {
1318                 pr_err("Data length is: %d\n", count->data_length);
1319                 return -1;
1320         }
1321
1322         memset(&msg, 0, sizeof(struct msghdr));
1323
1324         iov_p = count->iov;
1325         iov_len = count->iov_count;
1326
1327         ret = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1328                              count->data_length);
1329         if (ret != count->data_length) {
1330                 pr_err("Unexpected ret: %d send data %d\n",
1331                        ret, count->data_length);
1332                 return -EPIPE;
1333         }
1334         pr_debug("ret: %d, sent data: %d\n", ret, count->data_length);
1335
1336         return ret;
1337 }
1338
1339 int rx_data(
1340         struct iscsi_conn *conn,
1341         struct kvec *iov,
1342         int iov_count,
1343         int data)
1344 {
1345         struct iscsi_data_count c;
1346
1347         if (!conn || !conn->sock || !conn->conn_ops)
1348                 return -1;
1349
1350         memset(&c, 0, sizeof(struct iscsi_data_count));
1351         c.iov = iov;
1352         c.iov_count = iov_count;
1353         c.data_length = data;
1354         c.type = ISCSI_RX_DATA;
1355
1356         return iscsit_do_rx_data(conn, &c);
1357 }
1358
1359 int tx_data(
1360         struct iscsi_conn *conn,
1361         struct kvec *iov,
1362         int iov_count,
1363         int data)
1364 {
1365         struct iscsi_data_count c;
1366
1367         if (!conn || !conn->sock || !conn->conn_ops)
1368                 return -1;
1369
1370         memset(&c, 0, sizeof(struct iscsi_data_count));
1371         c.iov = iov;
1372         c.iov_count = iov_count;
1373         c.data_length = data;
1374         c.type = ISCSI_TX_DATA;
1375
1376         return iscsit_do_tx_data(conn, &c);
1377 }
1378
1379 static bool sockaddr_equal(struct sockaddr_storage *x, struct sockaddr_storage *y)
1380 {
1381         switch (x->ss_family) {
1382         case AF_INET: {
1383                 struct sockaddr_in *sinx = (struct sockaddr_in *)x;
1384                 struct sockaddr_in *siny = (struct sockaddr_in *)y;
1385                 if (sinx->sin_addr.s_addr != siny->sin_addr.s_addr)
1386                         return false;
1387                 if (sinx->sin_port != siny->sin_port)
1388                         return false;
1389                 break;
1390         }
1391         case AF_INET6: {
1392                 struct sockaddr_in6 *sinx = (struct sockaddr_in6 *)x;
1393                 struct sockaddr_in6 *siny = (struct sockaddr_in6 *)y;
1394                 if (!ipv6_addr_equal(&sinx->sin6_addr, &siny->sin6_addr))
1395                         return false;
1396                 if (sinx->sin6_port != siny->sin6_port)
1397                         return false;
1398                 break;
1399         }
1400         default:
1401                 return false;
1402         }
1403         return true;
1404 }
1405
1406 void iscsit_collect_login_stats(
1407         struct iscsi_conn *conn,
1408         u8 status_class,
1409         u8 status_detail)
1410 {
1411         struct iscsi_param *intrname = NULL;
1412         struct iscsi_tiqn *tiqn;
1413         struct iscsi_login_stats *ls;
1414
1415         tiqn = iscsit_snmp_get_tiqn(conn);
1416         if (!tiqn)
1417                 return;
1418
1419         ls = &tiqn->login_stats;
1420
1421         spin_lock(&ls->lock);
1422         if (sockaddr_equal(&conn->login_sockaddr, &ls->last_intr_fail_sockaddr) &&
1423             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1424                 /* We already have the failure info for this login */
1425                 spin_unlock(&ls->lock);
1426                 return;
1427         }
1428
1429         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1430                 ls->accepts++;
1431         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1432                 ls->redirects++;
1433                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1434         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1435                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1436                 ls->authenticate_fails++;
1437                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1438         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1439                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1440                 ls->authorize_fails++;
1441                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1442         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1443                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1444                 ls->negotiate_fails++;
1445                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1446         } else {
1447                 ls->other_fails++;
1448                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1449         }
1450
1451         /* Save initiator name, ip address and time, if it is a failed login */
1452         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1453                 if (conn->param_list)
1454                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1455                                                              conn->param_list);
1456                 strlcpy(ls->last_intr_fail_name,
1457                        (intrname ? intrname->value : "Unknown"),
1458                        sizeof(ls->last_intr_fail_name));
1459
1460                 ls->last_intr_fail_ip_family = conn->login_family;
1461
1462                 ls->last_intr_fail_sockaddr = conn->login_sockaddr;
1463                 ls->last_fail_time = get_jiffies_64();
1464         }
1465
1466         spin_unlock(&ls->lock);
1467 }
1468
1469 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1470 {
1471         struct iscsi_portal_group *tpg;
1472
1473         if (!conn || !conn->sess)
1474                 return NULL;
1475
1476         tpg = conn->sess->tpg;
1477         if (!tpg)
1478                 return NULL;
1479
1480         if (!tpg->tpg_tiqn)
1481                 return NULL;
1482
1483         return tpg->tpg_tiqn;
1484 }