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
 518 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 519 {
 520         struct iscsi_queue_req *qr;
 521
 522         spin_lock_bh(&conn->immed_queue_lock);
 523         if (list_empty(&conn->immed_queue_list)) {
 524                 spin_unlock_bh(&conn->immed_queue_lock);
 525                 return NULL;
 526         }
 527         qr = list_first_entry(&conn->immed_queue_list,
 528                               struct iscsi_queue_req, qr_list);
 529
 530         list_del(&qr->qr_list);
 531         if (qr->cmd)
 532                 atomic_dec(&qr->cmd->immed_queue_count);
 533         spin_unlock_bh(&conn->immed_queue_lock);
 534
 535         return qr;
 536 }
 537
 538 static void iscsit_remove_cmd_from_immediate_queue(
 539         struct iscsi_cmd *cmd,
 540         struct iscsi_conn *conn)
 541 {
 542         struct iscsi_queue_req *qr, *qr_tmp;
 543
 544         spin_lock_bh(&conn->immed_queue_lock);
 545         if (!atomic_read(&cmd->immed_queue_count)) {
 546                 spin_unlock_bh(&conn->immed_queue_lock);
 547                 return;
 548         }
 549
 550         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 551                 if (qr->cmd != cmd)
 552                         continue;
 553
 554                 atomic_dec(&qr->cmd->immed_queue_count);
 555                 list_del(&qr->qr_list);
 556                 kmem_cache_free(lio_qr_cache, qr);
 557         }
 558         spin_unlock_bh(&conn->immed_queue_lock);
 559
 560         if (atomic_read(&cmd->immed_queue_count)) {
 561                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 562                         cmd->init_task_tag,
 563                         atomic_read(&cmd->immed_queue_count));
 564         }
 565 }
 566
 567 void iscsit_add_cmd_to_response_queue(
 568         struct iscsi_cmd *cmd,
 569         struct iscsi_conn *conn,
 570         u8 state)
 571 {
 572         struct iscsi_queue_req *qr;
 573
 574         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 575         if (!qr) {
 576                 pr_err("Unable to allocate memory for"
 577                         " struct iscsi_queue_req\n");
 578                 return;
 579         }
 580         INIT_LIST_HEAD(&qr->qr_list);
 581         qr->cmd = cmd;
 582         qr->state = state;
 583
 584         spin_lock_bh(&conn->response_queue_lock);
 585         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 586         atomic_inc(&cmd->response_queue_count);
 587         spin_unlock_bh(&conn->response_queue_lock);
 588
 589         wake_up(&conn->queues_wq);
 590 }
 591
 592 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 593 {
 594         struct iscsi_queue_req *qr;
 595
 596         spin_lock_bh(&conn->response_queue_lock);
 597         if (list_empty(&conn->response_queue_list)) {
 598                 spin_unlock_bh(&conn->response_queue_lock);
 599                 return NULL;
 600         }
 601
 602         qr = list_first_entry(&conn->response_queue_list,
 603                               struct iscsi_queue_req, qr_list);
 604
 605         list_del(&qr->qr_list);
 606         if (qr->cmd)
 607                 atomic_dec(&qr->cmd->response_queue_count);
 608         spin_unlock_bh(&conn->response_queue_lock);
 609
 610         return qr;
 611 }
 612
 613 static void iscsit_remove_cmd_from_response_queue(
 614         struct iscsi_cmd *cmd,
 615         struct iscsi_conn *conn)
 616 {
 617         struct iscsi_queue_req *qr, *qr_tmp;
 618
 619         spin_lock_bh(&conn->response_queue_lock);
 620         if (!atomic_read(&cmd->response_queue_count)) {
 621                 spin_unlock_bh(&conn->response_queue_lock);
 622                 return;
 623         }
 624
 625         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 626                                 qr_list) {
 627                 if (qr->cmd != cmd)
 628                         continue;
 629
 630                 atomic_dec(&qr->cmd->response_queue_count);
 631                 list_del(&qr->qr_list);
 632                 kmem_cache_free(lio_qr_cache, qr);
 633         }
 634         spin_unlock_bh(&conn->response_queue_lock);
 635
 636         if (atomic_read(&cmd->response_queue_count)) {
 637                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 638                         cmd->init_task_tag,
 639                         atomic_read(&cmd->response_queue_count));
 640         }
 641 }
 642
 643 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 644 {
 645         bool empty;
 646
 647         spin_lock_bh(&conn->immed_queue_lock);
 648         empty = list_empty(&conn->immed_queue_list);
 649         spin_unlock_bh(&conn->immed_queue_lock);
 650
 651         if (!empty)
 652                 return empty;
 653
 654         spin_lock_bh(&conn->response_queue_lock);
 655         empty = list_empty(&conn->response_queue_list);
 656         spin_unlock_bh(&conn->response_queue_lock);
 657
 658         return empty;
 659 }
 660
 661 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 662 {
 663         struct iscsi_queue_req *qr, *qr_tmp;
 664
 665         spin_lock_bh(&conn->immed_queue_lock);
 666         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 667                 list_del(&qr->qr_list);
 668                 if (qr->cmd)
 669                         atomic_dec(&qr->cmd->immed_queue_count);
 670
 671                 kmem_cache_free(lio_qr_cache, qr);
 672         }
 673         spin_unlock_bh(&conn->immed_queue_lock);
 674
 675         spin_lock_bh(&conn->response_queue_lock);
 676         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 677                         qr_list) {
 678                 list_del(&qr->qr_list);
 679                 if (qr->cmd)
 680                         atomic_dec(&qr->cmd->response_queue_count);
 681
 682                 kmem_cache_free(lio_qr_cache, qr);
 683         }
 684         spin_unlock_bh(&conn->response_queue_lock);
 685 }
 686
 687 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 688 {
 689         struct iscsi_session *sess;
 690         struct se_cmd *se_cmd = &cmd->se_cmd;
 691
 692         if (cmd->conn)
 693                 sess = cmd->conn->sess;
 694         else
 695                 sess = cmd->sess;
 696
 697         BUG_ON(!sess || !sess->se_sess);
 698
 699         kfree(cmd->buf_ptr);
 700         kfree(cmd->pdu_list);
 701         kfree(cmd->seq_list);
 702         kfree(cmd->tmr_req);
 703         kfree(cmd->iov_data);
 704         kfree(cmd->text_in_ptr);
 705
 706         percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 707 }
 708 EXPORT_SYMBOL(iscsit_release_cmd);
 709
 710 void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool scsi_cmd,
 711                        bool check_queues)
 712 {
 713         struct iscsi_conn *conn = cmd->conn;
 714
 715         if (scsi_cmd) {
 716                 if (cmd->data_direction == DMA_TO_DEVICE) {
 717                         iscsit_stop_dataout_timer(cmd);
 718                         iscsit_free_r2ts_from_list(cmd);
 719                 }
 720                 if (cmd->data_direction == DMA_FROM_DEVICE)
 721                         iscsit_free_all_datain_reqs(cmd);
 722         }
 723
 724         if (conn && check_queues) {
 725                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 726                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 727         }
 728 }
 729
 730 void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 731 {
 732         struct se_cmd *se_cmd = NULL;
 733         int rc;
 734         bool op_scsi = false;
 735         /*
 736          * Determine if a struct se_cmd is associated with
 737          * this struct iscsi_cmd.
 738          */
 739         switch (cmd->iscsi_opcode) {
 740         case ISCSI_OP_SCSI_CMD:
 741                 op_scsi = true;
 742                 /*
 743                  * Fallthrough
 744                  */
 745         case ISCSI_OP_SCSI_TMFUNC:
 746                 se_cmd = &cmd->se_cmd;
 747                 __iscsit_free_cmd(cmd, op_scsi, shutdown);
 748                 rc = transport_generic_free_cmd(se_cmd, shutdown);
 749                 if (!rc && shutdown && se_cmd->se_sess) {
 750                         __iscsit_free_cmd(cmd, op_scsi, shutdown);
 751                         target_put_sess_cmd(se_cmd);
 752                 }
 753                 break;
 754         case ISCSI_OP_REJECT:
 755                 /*
 756                  * Handle special case for REJECT when iscsi_add_reject*() has
 757                  * overwritten the original iscsi_opcode assignment, and the
 758                  * associated cmd->se_cmd needs to be released.
 759                  */
 760                 if (cmd->se_cmd.se_tfo != NULL) {
 761                         se_cmd = &cmd->se_cmd;
 762                         __iscsit_free_cmd(cmd, true, shutdown);
 763
 764                         rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 765                         if (!rc && shutdown && se_cmd->se_sess) {
 766                                 __iscsit_free_cmd(cmd, true, shutdown);
 767                                 target_put_sess_cmd(se_cmd);
 768                         }
 769                         break;
 770                 }
 771                 /* Fall-through */
 772         default:
 773                 __iscsit_free_cmd(cmd, false, shutdown);
 774                 iscsit_release_cmd(cmd);
 775                 break;
 776         }
 777 }
 778
 779 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 780 {
 781         spin_lock_bh(&sess->session_usage_lock);
 782         if (sess->session_usage_count != 0) {
 783                 sess->session_waiting_on_uc = 1;
 784                 spin_unlock_bh(&sess->session_usage_lock);
 785                 if (in_interrupt())
 786                         return 2;
 787
 788                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 789                 return 1;
 790         }
 791         spin_unlock_bh(&sess->session_usage_lock);
 792
 793         return 0;
 794 }
 795
 796 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 797 {
 798         spin_lock_bh(&sess->session_usage_lock);
 799         sess->session_usage_count--;
 800
 801         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 802                 complete(&sess->session_waiting_on_uc_comp);
 803
 804         spin_unlock_bh(&sess->session_usage_lock);
 805 }
 806
 807 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 808 {
 809         spin_lock_bh(&sess->session_usage_lock);
 810         sess->session_usage_count++;
 811         spin_unlock_bh(&sess->session_usage_lock);
 812 }
 813
 814 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 815 {
 816         struct iscsi_conn *conn;
 817
 818         spin_lock_bh(&sess->conn_lock);
 819         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 820                 if ((conn->cid == cid) &&
 821                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 822                         iscsit_inc_conn_usage_count(conn);
 823                         spin_unlock_bh(&sess->conn_lock);
 824                         return conn;
 825                 }
 826         }
 827         spin_unlock_bh(&sess->conn_lock);
 828
 829         return NULL;
 830 }
 831
 832 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 833 {
 834         struct iscsi_conn *conn;
 835
 836         spin_lock_bh(&sess->conn_lock);
 837         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 838                 if (conn->cid == cid) {
 839                         iscsit_inc_conn_usage_count(conn);
 840                         spin_lock(&conn->state_lock);
 841                         atomic_set(&conn->connection_wait_rcfr, 1);
 842                         spin_unlock(&conn->state_lock);
 843                         spin_unlock_bh(&sess->conn_lock);
 844                         return conn;
 845                 }
 846         }
 847         spin_unlock_bh(&sess->conn_lock);
 848
 849         return NULL;
 850 }
 851
 852 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 853 {
 854         spin_lock_bh(&conn->conn_usage_lock);
 855         if (conn->conn_usage_count != 0) {
 856                 conn->conn_waiting_on_uc = 1;
 857                 spin_unlock_bh(&conn->conn_usage_lock);
 858
 859                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 860                 return;
 861         }
 862         spin_unlock_bh(&conn->conn_usage_lock);
 863 }
 864
 865 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 866 {
 867         spin_lock_bh(&conn->conn_usage_lock);
 868         conn->conn_usage_count--;
 869
 870         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 871                 complete(&conn->conn_waiting_on_uc_comp);
 872
 873         spin_unlock_bh(&conn->conn_usage_lock);
 874 }
 875
 876 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 877 {
 878         spin_lock_bh(&conn->conn_usage_lock);
 879         conn->conn_usage_count++;
 880         spin_unlock_bh(&conn->conn_usage_lock);
 881 }
 882
 883 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 884 {
 885         u8 state;
 886         struct iscsi_cmd *cmd;
 887
 888         cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
 889         if (!cmd)
 890                 return -1;
 891
 892         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 893         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 894                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 895         cmd->init_task_tag = RESERVED_ITT;
 896         cmd->targ_xfer_tag = (want_response) ?
 897                              session_get_next_ttt(conn->sess) : 0xFFFFFFFF;
 898         spin_lock_bh(&conn->cmd_lock);
 899         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 900         spin_unlock_bh(&conn->cmd_lock);
 901
 902         if (want_response)
 903                 iscsit_start_nopin_response_timer(conn);
 904         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 905
 906         return 0;
 907 }
 908
 909 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 910 {
 911         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 912
 913         iscsit_inc_conn_usage_count(conn);
 914
 915         spin_lock_bh(&conn->nopin_timer_lock);
 916         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 917                 spin_unlock_bh(&conn->nopin_timer_lock);
 918                 iscsit_dec_conn_usage_count(conn);
 919                 return;
 920         }
 921
 922         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 923                 " SID: %u, failing connection.\n", conn->cid,
 924                         conn->sess->sid);
 925         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 926         spin_unlock_bh(&conn->nopin_timer_lock);
 927
 928         {
 929         struct iscsi_portal_group *tpg = conn->sess->tpg;
 930         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 931
 932         if (tiqn) {
 933                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 934                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 935                                 conn->sess->sess_ops->InitiatorName);
 936                 tiqn->sess_err_stats.last_sess_failure_type =
 937                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 938                 tiqn->sess_err_stats.cxn_timeout_errors++;
 939                 atomic_long_inc(&conn->sess->conn_timeout_errors);
 940                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 941         }
 942         }
 943
 944         iscsit_cause_connection_reinstatement(conn, 0);
 945         iscsit_dec_conn_usage_count(conn);
 946 }
 947
 948 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 949 {
 950         struct iscsi_session *sess = conn->sess;
 951         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 952
 953         spin_lock_bh(&conn->nopin_timer_lock);
 954         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 955                 spin_unlock_bh(&conn->nopin_timer_lock);
 956                 return;
 957         }
 958
 959         mod_timer(&conn->nopin_response_timer,
 960                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
 961         spin_unlock_bh(&conn->nopin_timer_lock);
 962 }
 963
 964 /*
 965  *      Called with conn->nopin_timer_lock held.
 966  */
 967 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
 968 {
 969         struct iscsi_session *sess = conn->sess;
 970         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 971
 972         spin_lock_bh(&conn->nopin_timer_lock);
 973         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
 974                 spin_unlock_bh(&conn->nopin_timer_lock);
 975                 return;
 976         }
 977
 978         init_timer(&conn->nopin_response_timer);
 979         conn->nopin_response_timer.expires =
 980                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
 981         conn->nopin_response_timer.data = (unsigned long)conn;
 982         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
 983         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
 984         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
 985         add_timer(&conn->nopin_response_timer);
 986
 987         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
 988                 " seconds\n", conn->cid, na->nopin_response_timeout);
 989         spin_unlock_bh(&conn->nopin_timer_lock);
 990 }
 991
 992 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
 993 {
 994         spin_lock_bh(&conn->nopin_timer_lock);
 995         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 996                 spin_unlock_bh(&conn->nopin_timer_lock);
 997                 return;
 998         }
 999         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1000         spin_unlock_bh(&conn->nopin_timer_lock);
1001
1002         del_timer_sync(&conn->nopin_response_timer);
1003
1004         spin_lock_bh(&conn->nopin_timer_lock);
1005         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1006         spin_unlock_bh(&conn->nopin_timer_lock);
1007 }
1008
1009 static void iscsit_handle_nopin_timeout(unsigned long data)
1010 {
1011         struct iscsi_conn *conn = (struct iscsi_conn *) data;
1012
1013         iscsit_inc_conn_usage_count(conn);
1014
1015         spin_lock_bh(&conn->nopin_timer_lock);
1016         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1017                 spin_unlock_bh(&conn->nopin_timer_lock);
1018                 iscsit_dec_conn_usage_count(conn);
1019                 return;
1020         }
1021         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1022         spin_unlock_bh(&conn->nopin_timer_lock);
1023
1024         iscsit_add_nopin(conn, 1);
1025         iscsit_dec_conn_usage_count(conn);
1026 }
1027
1028 /*
1029  * Called with conn->nopin_timer_lock held.
1030  */
1031 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1032 {
1033         struct iscsi_session *sess = conn->sess;
1034         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1035         /*
1036         * NOPIN timeout is disabled.
1037          */
1038         if (!na->nopin_timeout)
1039                 return;
1040
1041         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1042                 return;
1043
1044         init_timer(&conn->nopin_timer);
1045         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1046         conn->nopin_timer.data = (unsigned long)conn;
1047         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1048         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1049         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1050         add_timer(&conn->nopin_timer);
1051
1052         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1053                 " interval\n", conn->cid, na->nopin_timeout);
1054 }
1055
1056 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1057 {
1058         struct iscsi_session *sess = conn->sess;
1059         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1060         /*
1061          * NOPIN timeout is disabled..
1062          */
1063         if (!na->nopin_timeout)
1064                 return;
1065
1066         spin_lock_bh(&conn->nopin_timer_lock);
1067         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1068                 spin_unlock_bh(&conn->nopin_timer_lock);
1069                 return;
1070         }
1071
1072         init_timer(&conn->nopin_timer);
1073         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1074         conn->nopin_timer.data = (unsigned long)conn;
1075         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1076         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1077         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1078         add_timer(&conn->nopin_timer);
1079
1080         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1081                         " interval\n", conn->cid, na->nopin_timeout);
1082         spin_unlock_bh(&conn->nopin_timer_lock);
1083 }
1084
1085 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1086 {
1087         spin_lock_bh(&conn->nopin_timer_lock);
1088         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1089                 spin_unlock_bh(&conn->nopin_timer_lock);
1090                 return;
1091         }
1092         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1093         spin_unlock_bh(&conn->nopin_timer_lock);
1094
1095         del_timer_sync(&conn->nopin_timer);
1096
1097         spin_lock_bh(&conn->nopin_timer_lock);
1098         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1099         spin_unlock_bh(&conn->nopin_timer_lock);
1100 }
1101
1102 int iscsit_send_tx_data(
1103         struct iscsi_cmd *cmd,
1104         struct iscsi_conn *conn,
1105         int use_misc)
1106 {
1107         int tx_sent, tx_size;
1108         u32 iov_count;
1109         struct kvec *iov;
1110
1111 send_data:
1112         tx_size = cmd->tx_size;
1113
1114         if (!use_misc) {
1115                 iov = &cmd->iov_data[0];
1116                 iov_count = cmd->iov_data_count;
1117         } else {
1118                 iov = &cmd->iov_misc[0];
1119                 iov_count = cmd->iov_misc_count;
1120         }
1121
1122         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1123         if (tx_size != tx_sent) {
1124                 if (tx_sent == -EAGAIN) {
1125                         pr_err("tx_data() returned -EAGAIN\n");
1126                         goto send_data;
1127                 } else
1128                         return -1;
1129         }
1130         cmd->tx_size = 0;
1131
1132         return 0;
1133 }
1134
1135 int iscsit_fe_sendpage_sg(
1136         struct iscsi_cmd *cmd,
1137         struct iscsi_conn *conn)
1138 {
1139         struct scatterlist *sg = cmd->first_data_sg;
1140         struct kvec iov;
1141         u32 tx_hdr_size, data_len;
1142         u32 offset = cmd->first_data_sg_off;
1143         int tx_sent, iov_off;
1144
1145 send_hdr:
1146         tx_hdr_size = ISCSI_HDR_LEN;
1147         if (conn->conn_ops->HeaderDigest)
1148                 tx_hdr_size += ISCSI_CRC_LEN;
1149
1150         iov.iov_base = cmd->pdu;
1151         iov.iov_len = tx_hdr_size;
1152
1153         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1154         if (tx_hdr_size != tx_sent) {
1155                 if (tx_sent == -EAGAIN) {
1156                         pr_err("tx_data() returned -EAGAIN\n");
1157                         goto send_hdr;
1158                 }
1159                 return -1;
1160         }
1161
1162         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1163         /*
1164          * Set iov_off used by padding and data digest tx_data() calls below
1165          * in order to determine proper offset into cmd->iov_data[]
1166          */
1167         if (conn->conn_ops->DataDigest) {
1168                 data_len -= ISCSI_CRC_LEN;
1169                 if (cmd->padding)
1170                         iov_off = (cmd->iov_data_count - 2);
1171                 else
1172                         iov_off = (cmd->iov_data_count - 1);
1173         } else {
1174                 iov_off = (cmd->iov_data_count - 1);
1175         }
1176         /*
1177          * Perform sendpage() for each page in the scatterlist
1178          */
1179         while (data_len) {
1180                 u32 space = (sg->length - offset);
1181                 u32 sub_len = min_t(u32, data_len, space);
1182 send_pg:
1183                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1184                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1185                 if (tx_sent != sub_len) {
1186                         if (tx_sent == -EAGAIN) {
1187                                 pr_err("tcp_sendpage() returned"
1188                                                 " -EAGAIN\n");
1189                                 goto send_pg;
1190                         }
1191
1192                         pr_err("tcp_sendpage() failure: %d\n",
1193                                         tx_sent);
1194                         return -1;
1195                 }
1196
1197                 data_len -= sub_len;
1198                 offset = 0;
1199                 sg = sg_next(sg);
1200         }
1201
1202 send_padding:
1203         if (cmd->padding) {
1204                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1205
1206                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1207                 if (cmd->padding != tx_sent) {
1208                         if (tx_sent == -EAGAIN) {
1209                                 pr_err("tx_data() returned -EAGAIN\n");
1210                                 goto send_padding;
1211                         }
1212                         return -1;
1213                 }
1214         }
1215
1216 send_datacrc:
1217         if (conn->conn_ops->DataDigest) {
1218                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1219
1220                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1221                 if (ISCSI_CRC_LEN != tx_sent) {
1222                         if (tx_sent == -EAGAIN) {
1223                                 pr_err("tx_data() returned -EAGAIN\n");
1224                                 goto send_datacrc;
1225                         }
1226                         return -1;
1227                 }
1228         }
1229
1230         return 0;
1231 }
1232
1233 /*
1234  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1235  *      back to the Initiator when an expection condition occurs with the
1236  *      errors set in status_class and status_detail.
1237  *
1238  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1239  *      Returns:        0 on success, -1 on error.
1240  */
1241 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1242 {
1243         struct iscsi_login_rsp *hdr;
1244         struct iscsi_login *login = conn->conn_login;
1245
1246         login->login_failed = 1;
1247         iscsit_collect_login_stats(conn, status_class, status_detail);
1248
1249         memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1250
1251         hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1252         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1253         hdr->status_class       = status_class;
1254         hdr->status_detail      = status_detail;
1255         hdr->itt                = conn->login_itt;
1256
1257         return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1258 }
1259
1260 void iscsit_print_session_params(struct iscsi_session *sess)
1261 {
1262         struct iscsi_conn *conn;
1263
1264         pr_debug("-----------------------------[Session Params for"
1265                 " SID: %u]-----------------------------\n", sess->sid);
1266         spin_lock_bh(&sess->conn_lock);
1267         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1268                 iscsi_dump_conn_ops(conn->conn_ops);
1269         spin_unlock_bh(&sess->conn_lock);
1270
1271         iscsi_dump_sess_ops(sess->sess_ops);
1272 }
1273
1274 static int iscsit_do_rx_data(
1275         struct iscsi_conn *conn,
1276         struct iscsi_data_count *count)
1277 {
1278         int data = count->data_length, rx_loop = 0, total_rx = 0;
1279         struct msghdr msg;
1280
1281         if (!conn || !conn->sock || !conn->conn_ops)
1282                 return -1;
1283
1284         memset(&msg, 0, sizeof(struct msghdr));
1285         iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC,
1286                       count->iov, count->iov_count, data);
1287
1288         while (total_rx < data) {
1289                 rx_loop = sock_recvmsg(conn->sock, &msg,
1290                                       (data - total_rx), MSG_WAITALL);
1291                 if (rx_loop <= 0) {
1292                         pr_debug("rx_loop: %d total_rx: %d\n",
1293                                 rx_loop, total_rx);
1294                         return rx_loop;
1295                 }
1296                 total_rx += rx_loop;
1297                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1298                                 rx_loop, total_rx, data);
1299         }
1300
1301         return total_rx;
1302 }
1303
1304 static int iscsit_do_tx_data(
1305         struct iscsi_conn *conn,
1306         struct iscsi_data_count *count)
1307 {
1308         int ret, iov_len;
1309         struct kvec *iov_p;
1310         struct msghdr msg;
1311
1312         if (!conn || !conn->sock || !conn->conn_ops)
1313                 return -1;
1314
1315         if (count->data_length <= 0) {
1316                 pr_err("Data length is: %d\n", count->data_length);
1317                 return -1;
1318         }
1319
1320         memset(&msg, 0, sizeof(struct msghdr));
1321
1322         iov_p = count->iov;
1323         iov_len = count->iov_count;
1324
1325         ret = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1326                              count->data_length);
1327         if (ret != count->data_length) {
1328                 pr_err("Unexpected ret: %d send data %d\n",
1329                        ret, count->data_length);
1330                 return -EPIPE;
1331         }
1332         pr_debug("ret: %d, sent data: %d\n", ret, count->data_length);
1333
1334         return ret;
1335 }
1336
1337 int rx_data(
1338         struct iscsi_conn *conn,
1339         struct kvec *iov,
1340         int iov_count,
1341         int data)
1342 {
1343         struct iscsi_data_count c;
1344
1345         if (!conn || !conn->sock || !conn->conn_ops)
1346                 return -1;
1347
1348         memset(&c, 0, sizeof(struct iscsi_data_count));
1349         c.iov = iov;
1350         c.iov_count = iov_count;
1351         c.data_length = data;
1352         c.type = ISCSI_RX_DATA;
1353
1354         return iscsit_do_rx_data(conn, &c);
1355 }
1356
1357 int tx_data(
1358         struct iscsi_conn *conn,
1359         struct kvec *iov,
1360         int iov_count,
1361         int data)
1362 {
1363         struct iscsi_data_count c;
1364
1365         if (!conn || !conn->sock || !conn->conn_ops)
1366                 return -1;
1367
1368         memset(&c, 0, sizeof(struct iscsi_data_count));
1369         c.iov = iov;
1370         c.iov_count = iov_count;
1371         c.data_length = data;
1372         c.type = ISCSI_TX_DATA;
1373
1374         return iscsit_do_tx_data(conn, &c);
1375 }
1376
1377 static bool sockaddr_equal(struct sockaddr_storage *x, struct sockaddr_storage *y)
1378 {
1379         switch (x->ss_family) {
1380         case AF_INET: {
1381                 struct sockaddr_in *sinx = (struct sockaddr_in *)x;
1382                 struct sockaddr_in *siny = (struct sockaddr_in *)y;
1383                 if (sinx->sin_addr.s_addr != siny->sin_addr.s_addr)
1384                         return false;
1385                 if (sinx->sin_port != siny->sin_port)
1386                         return false;
1387                 break;
1388         }
1389         case AF_INET6: {
1390                 struct sockaddr_in6 *sinx = (struct sockaddr_in6 *)x;
1391                 struct sockaddr_in6 *siny = (struct sockaddr_in6 *)y;
1392                 if (!ipv6_addr_equal(&sinx->sin6_addr, &siny->sin6_addr))
1393                         return false;
1394                 if (sinx->sin6_port != siny->sin6_port)
1395                         return false;
1396                 break;
1397         }
1398         default:
1399                 return false;
1400         }
1401         return true;
1402 }
1403
1404 void iscsit_collect_login_stats(
1405         struct iscsi_conn *conn,
1406         u8 status_class,
1407         u8 status_detail)
1408 {
1409         struct iscsi_param *intrname = NULL;
1410         struct iscsi_tiqn *tiqn;
1411         struct iscsi_login_stats *ls;
1412
1413         tiqn = iscsit_snmp_get_tiqn(conn);
1414         if (!tiqn)
1415                 return;
1416
1417         ls = &tiqn->login_stats;
1418
1419         spin_lock(&ls->lock);
1420         if (sockaddr_equal(&conn->login_sockaddr, &ls->last_intr_fail_sockaddr) &&
1421             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1422                 /* We already have the failure info for this login */
1423                 spin_unlock(&ls->lock);
1424                 return;
1425         }
1426
1427         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1428                 ls->accepts++;
1429         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1430                 ls->redirects++;
1431                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1432         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1433                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1434                 ls->authenticate_fails++;
1435                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1436         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1437                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1438                 ls->authorize_fails++;
1439                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1440         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1441                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1442                 ls->negotiate_fails++;
1443                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1444         } else {
1445                 ls->other_fails++;
1446                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1447         }
1448
1449         /* Save initiator name, ip address and time, if it is a failed login */
1450         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1451                 if (conn->param_list)
1452                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1453                                                              conn->param_list);
1454                 strlcpy(ls->last_intr_fail_name,
1455                        (intrname ? intrname->value : "Unknown"),
1456                        sizeof(ls->last_intr_fail_name));
1457
1458                 ls->last_intr_fail_ip_family = conn->login_family;
1459
1460                 ls->last_intr_fail_sockaddr = conn->login_sockaddr;
1461                 ls->last_fail_time = get_jiffies_64();
1462         }
1463
1464         spin_unlock(&ls->lock);
1465 }
1466
1467 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1468 {
1469         struct iscsi_portal_group *tpg;
1470
1471         if (!conn || !conn->sess)
1472                 return NULL;
1473
1474         tpg = conn->sess->tpg;
1475         if (!tpg)
1476                 return NULL;
1477
1478         if (!tpg->tpg_tiqn)
1479                 return NULL;
1480
1481         return tpg->tpg_tiqn;
1482 }