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/target_core_configfs.h>
  26 #include <target/iscsi/iscsi_transport.h>
  27
  28 #include "iscsi_target_core.h"
  29 #include "iscsi_target_parameters.h"
  30 #include "iscsi_target_seq_pdu_list.h"
  31 #include "iscsi_target_datain_values.h"
  32 #include "iscsi_target_erl0.h"
  33 #include "iscsi_target_erl1.h"
  34 #include "iscsi_target_erl2.h"
  35 #include "iscsi_target_tpg.h"
  36 #include "iscsi_target_tq.h"
  37 #include "iscsi_target_util.h"
  38 #include "iscsi_target.h"
  39
  40 #define PRINT_BUFF(buff, len)                                   \
  41 {                                                               \
  42         int zzz;                                                \
  43                                                                 \
  44         pr_debug("%d:\n", __LINE__);                            \
  45         for (zzz = 0; zzz < len; zzz++) {                       \
  46                 if (zzz % 16 == 0) {                            \
  47                         if (zzz)                                \
  48                                 pr_debug("\n");                 \
  49                         pr_debug("%4i: ", zzz);                 \
  50                 }                                               \
  51                 pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  52         }                                                       \
  53         if ((len + 1) % 16)                                     \
  54                 pr_debug("\n");                                 \
  55 }
  56
  57 extern struct list_head g_tiqn_list;
  58 extern spinlock_t tiqn_lock;
  59
  60 /*
  61  *      Called with cmd->r2t_lock held.
  62  */
  63 int iscsit_add_r2t_to_list(
  64         struct iscsi_cmd *cmd,
  65         u32 offset,
  66         u32 xfer_len,
  67         int recovery,
  68         u32 r2t_sn)
  69 {
  70         struct iscsi_r2t *r2t;
  71
  72         r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  73         if (!r2t) {
  74                 pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  75                 return -1;
  76         }
  77         INIT_LIST_HEAD(&r2t->r2t_list);
  78
  79         r2t->recovery_r2t = recovery;
  80         r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  81         r2t->offset = offset;
  82         r2t->xfer_len = xfer_len;
  83         list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  84         spin_unlock_bh(&cmd->r2t_lock);
  85
  86         iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  87
  88         spin_lock_bh(&cmd->r2t_lock);
  89         return 0;
  90 }
  91
  92 struct iscsi_r2t *iscsit_get_r2t_for_eos(
  93         struct iscsi_cmd *cmd,
  94         u32 offset,
  95         u32 length)
  96 {
  97         struct iscsi_r2t *r2t;
  98
  99         spin_lock_bh(&cmd->r2t_lock);
 100         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 101                 if ((r2t->offset <= offset) &&
 102                     (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 103                         spin_unlock_bh(&cmd->r2t_lock);
 104                         return r2t;
 105                 }
 106         }
 107         spin_unlock_bh(&cmd->r2t_lock);
 108
 109         pr_err("Unable to locate R2T for Offset: %u, Length:"
 110                         " %u\n", offset, length);
 111         return NULL;
 112 }
 113
 114 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 115 {
 116         struct iscsi_r2t *r2t;
 117
 118         spin_lock_bh(&cmd->r2t_lock);
 119         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 120                 if (!r2t->sent_r2t) {
 121                         spin_unlock_bh(&cmd->r2t_lock);
 122                         return r2t;
 123                 }
 124         }
 125         spin_unlock_bh(&cmd->r2t_lock);
 126
 127         pr_err("Unable to locate next R2T to send for ITT:"
 128                         " 0x%08x.\n", cmd->init_task_tag);
 129         return NULL;
 130 }
 131
 132 /*
 133  *      Called with cmd->r2t_lock held.
 134  */
 135 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 136 {
 137         list_del(&r2t->r2t_list);
 138         kmem_cache_free(lio_r2t_cache, r2t);
 139 }
 140
 141 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 142 {
 143         struct iscsi_r2t *r2t, *r2t_tmp;
 144
 145         spin_lock_bh(&cmd->r2t_lock);
 146         list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 147                 iscsit_free_r2t(r2t, cmd);
 148         spin_unlock_bh(&cmd->r2t_lock);
 149 }
 150
 151 /*
 152  * May be called from software interrupt (timer) context for allocating
 153  * iSCSI NopINs.
 154  */
 155 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, int state)
 156 {
 157         struct iscsi_cmd *cmd;
 158         struct se_session *se_sess = conn->sess->se_sess;
 159         int size, tag;
 160
 161         tag = percpu_ida_alloc(&se_sess->sess_tag_pool, state);
 162         if (tag < 0)
 163                 return NULL;
 164
 165         size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
 166         cmd = (struct iscsi_cmd *)(se_sess->sess_cmd_map + (tag * size));
 167         memset(cmd, 0, size);
 168
 169         cmd->se_cmd.map_tag = tag;
 170         cmd->conn = conn;
 171         INIT_LIST_HEAD(&cmd->i_conn_node);
 172         INIT_LIST_HEAD(&cmd->datain_list);
 173         INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 174         spin_lock_init(&cmd->datain_lock);
 175         spin_lock_init(&cmd->dataout_timeout_lock);
 176         spin_lock_init(&cmd->istate_lock);
 177         spin_lock_init(&cmd->error_lock);
 178         spin_lock_init(&cmd->r2t_lock);
 179
 180         return cmd;
 181 }
 182 EXPORT_SYMBOL(iscsit_allocate_cmd);
 183
 184 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 185         struct iscsi_cmd *cmd,
 186         u32 seq_send_order)
 187 {
 188         u32 i;
 189
 190         for (i = 0; i < cmd->seq_count; i++)
 191                 if (cmd->seq_list[i].seq_send_order == seq_send_order)
 192                         return &cmd->seq_list[i];
 193
 194         return NULL;
 195 }
 196
 197 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 198 {
 199         u32 i;
 200
 201         if (!cmd->seq_list) {
 202                 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 203                 return NULL;
 204         }
 205
 206         for (i = 0; i < cmd->seq_count; i++) {
 207                 if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 208                         continue;
 209                 if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 210                         cmd->seq_send_order++;
 211                         return &cmd->seq_list[i];
 212                 }
 213         }
 214
 215         return NULL;
 216 }
 217
 218 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 219         struct iscsi_cmd *cmd,
 220         u32 r2t_sn)
 221 {
 222         struct iscsi_r2t *r2t;
 223
 224         spin_lock_bh(&cmd->r2t_lock);
 225         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 226                 if (r2t->r2t_sn == r2t_sn) {
 227                         spin_unlock_bh(&cmd->r2t_lock);
 228                         return r2t;
 229                 }
 230         }
 231         spin_unlock_bh(&cmd->r2t_lock);
 232
 233         return NULL;
 234 }
 235
 236 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 237 {
 238         int ret;
 239
 240         /*
 241          * This is the proper method of checking received CmdSN against
 242          * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 243          * or order CmdSNs due to multiple connection sessions and/or
 244          * CRC failures.
 245          */
 246         if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) {
 247                 pr_err("Received CmdSN: 0x%08x is greater than"
 248                        " MaxCmdSN: 0x%08x, ignoring.\n", cmdsn,
 249                        sess->max_cmd_sn);
 250                 ret = CMDSN_MAXCMDSN_OVERRUN;
 251
 252         } else if (cmdsn == sess->exp_cmd_sn) {
 253                 sess->exp_cmd_sn++;
 254                 pr_debug("Received CmdSN matches ExpCmdSN,"
 255                       " incremented ExpCmdSN to: 0x%08x\n",
 256                       sess->exp_cmd_sn);
 257                 ret = CMDSN_NORMAL_OPERATION;
 258
 259         } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 260                 pr_debug("Received CmdSN: 0x%08x is greater"
 261                       " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 262                       cmdsn, sess->exp_cmd_sn);
 263                 ret = CMDSN_HIGHER_THAN_EXP;
 264
 265         } else {
 266                 pr_err("Received CmdSN: 0x%08x is less than"
 267                        " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 268                        sess->exp_cmd_sn);
 269                 ret = CMDSN_LOWER_THAN_EXP;
 270         }
 271
 272         return ret;
 273 }
 274
 275 /*
 276  * Commands may be received out of order if MC/S is in use.
 277  * Ensure they are executed in CmdSN order.
 278  */
 279 int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 280                         unsigned char *buf, __be32 cmdsn)
 281 {
 282         int ret, cmdsn_ret;
 283         bool reject = false;
 284         u8 reason = ISCSI_REASON_BOOKMARK_NO_RESOURCES;
 285
 286         mutex_lock(&conn->sess->cmdsn_mutex);
 287
 288         cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
 289         switch (cmdsn_ret) {
 290         case CMDSN_NORMAL_OPERATION:
 291                 ret = iscsit_execute_cmd(cmd, 0);
 292                 if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 293                         iscsit_execute_ooo_cmdsns(conn->sess);
 294                 else if (ret < 0) {
 295                         reject = true;
 296                         ret = CMDSN_ERROR_CANNOT_RECOVER;
 297                 }
 298                 break;
 299         case CMDSN_HIGHER_THAN_EXP:
 300                 ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
 301                 if (ret < 0) {
 302                         reject = true;
 303                         ret = CMDSN_ERROR_CANNOT_RECOVER;
 304                         break;
 305                 }
 306                 ret = CMDSN_HIGHER_THAN_EXP;
 307                 break;
 308         case CMDSN_LOWER_THAN_EXP:
 309         case CMDSN_MAXCMDSN_OVERRUN:
 310         default:
 311                 cmd->i_state = ISTATE_REMOVE;
 312                 iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 313                 /*
 314                  * Existing callers for iscsit_sequence_cmd() will silently
 315                  * ignore commands with CMDSN_LOWER_THAN_EXP, so force this
 316                  * return for CMDSN_MAXCMDSN_OVERRUN as well..
 317                  */
 318                 ret = CMDSN_LOWER_THAN_EXP;
 319                 break;
 320         }
 321         mutex_unlock(&conn->sess->cmdsn_mutex);
 322
 323         if (reject)
 324                 iscsit_reject_cmd(cmd, reason, buf);
 325
 326         return ret;
 327 }
 328 EXPORT_SYMBOL(iscsit_sequence_cmd);
 329
 330 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 331 {
 332         struct iscsi_conn *conn = cmd->conn;
 333         struct se_cmd *se_cmd = &cmd->se_cmd;
 334         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 335         u32 payload_length = ntoh24(hdr->dlength);
 336
 337         if (conn->sess->sess_ops->InitialR2T) {
 338                 pr_err("Received unexpected unsolicited data"
 339                         " while InitialR2T=Yes, protocol error.\n");
 340                 transport_send_check_condition_and_sense(se_cmd,
 341                                 TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 342                 return -1;
 343         }
 344
 345         if ((cmd->first_burst_len + payload_length) >
 346              conn->sess->sess_ops->FirstBurstLength) {
 347                 pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 348                         " for this Unsolicited DataOut Burst.\n",
 349                         (cmd->first_burst_len + payload_length),
 350                                 conn->sess->sess_ops->FirstBurstLength);
 351                 transport_send_check_condition_and_sense(se_cmd,
 352                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 353                 return -1;
 354         }
 355
 356         if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 357                 return 0;
 358
 359         if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 360             ((cmd->first_burst_len + payload_length) !=
 361               conn->sess->sess_ops->FirstBurstLength)) {
 362                 pr_err("Unsolicited non-immediate data received %u"
 363                         " does not equal FirstBurstLength: %u, and does"
 364                         " not equal ExpXferLen %u.\n",
 365                         (cmd->first_burst_len + payload_length),
 366                         conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 367                 transport_send_check_condition_and_sense(se_cmd,
 368                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 369                 return -1;
 370         }
 371         return 0;
 372 }
 373
 374 struct iscsi_cmd *iscsit_find_cmd_from_itt(
 375         struct iscsi_conn *conn,
 376         itt_t init_task_tag)
 377 {
 378         struct iscsi_cmd *cmd;
 379
 380         spin_lock_bh(&conn->cmd_lock);
 381         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 382                 if (cmd->init_task_tag == init_task_tag) {
 383                         spin_unlock_bh(&conn->cmd_lock);
 384                         return cmd;
 385                 }
 386         }
 387         spin_unlock_bh(&conn->cmd_lock);
 388
 389         pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 390                         init_task_tag, conn->cid);
 391         return NULL;
 392 }
 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         /*
 735          * Determine if a struct se_cmd is associated with
 736          * this struct iscsi_cmd.
 737          */
 738         switch (cmd->iscsi_opcode) {
 739         case ISCSI_OP_SCSI_CMD:
 740                 se_cmd = &cmd->se_cmd;
 741                 __iscsit_free_cmd(cmd, true, shutdown);
 742                 /*
 743                  * Fallthrough
 744                  */
 745         case ISCSI_OP_SCSI_TMFUNC:
 746                 rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 747                 if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
 748                         __iscsit_free_cmd(cmd, true, shutdown);
 749                         target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 750                 }
 751                 break;
 752         case ISCSI_OP_REJECT:
 753                 /*
 754                  * Handle special case for REJECT when iscsi_add_reject*() has
 755                  * overwritten the original iscsi_opcode assignment, and the
 756                  * associated cmd->se_cmd needs to be released.
 757                  */
 758                 if (cmd->se_cmd.se_tfo != NULL) {
 759                         se_cmd = &cmd->se_cmd;
 760                         __iscsit_free_cmd(cmd, true, shutdown);
 761
 762                         rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 763                         if (!rc && shutdown && se_cmd->se_sess) {
 764                                 __iscsit_free_cmd(cmd, true, shutdown);
 765                                 target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 766                         }
 767                         break;
 768                 }
 769                 /* Fall-through */
 770         default:
 771                 __iscsit_free_cmd(cmd, false, shutdown);
 772                 iscsit_release_cmd(cmd);
 773                 break;
 774         }
 775 }
 776
 777 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 778 {
 779         spin_lock_bh(&sess->session_usage_lock);
 780         if (sess->session_usage_count != 0) {
 781                 sess->session_waiting_on_uc = 1;
 782                 spin_unlock_bh(&sess->session_usage_lock);
 783                 if (in_interrupt())
 784                         return 2;
 785
 786                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 787                 return 1;
 788         }
 789         spin_unlock_bh(&sess->session_usage_lock);
 790
 791         return 0;
 792 }
 793
 794 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 795 {
 796         spin_lock_bh(&sess->session_usage_lock);
 797         sess->session_usage_count--;
 798
 799         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 800                 complete(&sess->session_waiting_on_uc_comp);
 801
 802         spin_unlock_bh(&sess->session_usage_lock);
 803 }
 804
 805 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 806 {
 807         spin_lock_bh(&sess->session_usage_lock);
 808         sess->session_usage_count++;
 809         spin_unlock_bh(&sess->session_usage_lock);
 810 }
 811
 812 /*
 813  *      Setup conn->if_marker and conn->of_marker values based upon
 814  *      the initial marker-less interval. (see iSCSI v19 A.2)
 815  */
 816 int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 817 {
 818         int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 819         /*
 820          * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 821          */
 822         u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 823         u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 824
 825         if (conn->conn_ops->OFMarker) {
 826                 /*
 827                  * Account for the first Login Command received not
 828                  * via iscsi_recv_msg().
 829                  */
 830                 conn->of_marker += ISCSI_HDR_LEN;
 831                 if (conn->of_marker <= OFMarkInt) {
 832                         conn->of_marker = (OFMarkInt - conn->of_marker);
 833                 } else {
 834                         login_ofmarker_count = (conn->of_marker / OFMarkInt);
 835                         next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 836                                         (login_ofmarker_count * MARKER_SIZE);
 837                         conn->of_marker = (next_marker - conn->of_marker);
 838                 }
 839                 conn->of_marker_offset = 0;
 840                 pr_debug("Setting OFMarker value to %u based on Initial"
 841                         " Markerless Interval.\n", conn->of_marker);
 842         }
 843
 844         if (conn->conn_ops->IFMarker) {
 845                 if (conn->if_marker <= IFMarkInt) {
 846                         conn->if_marker = (IFMarkInt - conn->if_marker);
 847                 } else {
 848                         login_ifmarker_count = (conn->if_marker / IFMarkInt);
 849                         next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 850                                         (login_ifmarker_count * MARKER_SIZE);
 851                         conn->if_marker = (next_marker - conn->if_marker);
 852                 }
 853                 pr_debug("Setting IFMarker value to %u based on Initial"
 854                         " Markerless Interval.\n", conn->if_marker);
 855         }
 856
 857         return 0;
 858 }
 859
 860 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 861 {
 862         struct iscsi_conn *conn;
 863
 864         spin_lock_bh(&sess->conn_lock);
 865         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 866                 if ((conn->cid == cid) &&
 867                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 868                         iscsit_inc_conn_usage_count(conn);
 869                         spin_unlock_bh(&sess->conn_lock);
 870                         return conn;
 871                 }
 872         }
 873         spin_unlock_bh(&sess->conn_lock);
 874
 875         return NULL;
 876 }
 877
 878 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 879 {
 880         struct iscsi_conn *conn;
 881
 882         spin_lock_bh(&sess->conn_lock);
 883         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 884                 if (conn->cid == cid) {
 885                         iscsit_inc_conn_usage_count(conn);
 886                         spin_lock(&conn->state_lock);
 887                         atomic_set(&conn->connection_wait_rcfr, 1);
 888                         spin_unlock(&conn->state_lock);
 889                         spin_unlock_bh(&sess->conn_lock);
 890                         return conn;
 891                 }
 892         }
 893         spin_unlock_bh(&sess->conn_lock);
 894
 895         return NULL;
 896 }
 897
 898 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 899 {
 900         spin_lock_bh(&conn->conn_usage_lock);
 901         if (conn->conn_usage_count != 0) {
 902                 conn->conn_waiting_on_uc = 1;
 903                 spin_unlock_bh(&conn->conn_usage_lock);
 904
 905                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 906                 return;
 907         }
 908         spin_unlock_bh(&conn->conn_usage_lock);
 909 }
 910
 911 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 912 {
 913         spin_lock_bh(&conn->conn_usage_lock);
 914         conn->conn_usage_count--;
 915
 916         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 917                 complete(&conn->conn_waiting_on_uc_comp);
 918
 919         spin_unlock_bh(&conn->conn_usage_lock);
 920 }
 921
 922 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 923 {
 924         spin_lock_bh(&conn->conn_usage_lock);
 925         conn->conn_usage_count++;
 926         spin_unlock_bh(&conn->conn_usage_lock);
 927 }
 928
 929 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 930 {
 931         u8 state;
 932         struct iscsi_cmd *cmd;
 933
 934         cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
 935         if (!cmd)
 936                 return -1;
 937
 938         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 939         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 940                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 941         cmd->init_task_tag = RESERVED_ITT;
 942         spin_lock_bh(&conn->sess->ttt_lock);
 943         cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
 944                         0xFFFFFFFF;
 945         if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
 946                 cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
 947         spin_unlock_bh(&conn->sess->ttt_lock);
 948
 949         spin_lock_bh(&conn->cmd_lock);
 950         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 951         spin_unlock_bh(&conn->cmd_lock);
 952
 953         if (want_response)
 954                 iscsit_start_nopin_response_timer(conn);
 955         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 956
 957         return 0;
 958 }
 959
 960 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 961 {
 962         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 963
 964         iscsit_inc_conn_usage_count(conn);
 965
 966         spin_lock_bh(&conn->nopin_timer_lock);
 967         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 968                 spin_unlock_bh(&conn->nopin_timer_lock);
 969                 iscsit_dec_conn_usage_count(conn);
 970                 return;
 971         }
 972
 973         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 974                 " SID: %u, failing connection.\n", conn->cid,
 975                         conn->sess->sid);
 976         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 977         spin_unlock_bh(&conn->nopin_timer_lock);
 978
 979         {
 980         struct iscsi_portal_group *tpg = conn->sess->tpg;
 981         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 982
 983         if (tiqn) {
 984                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 985                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 986                                 conn->sess->sess_ops->InitiatorName);
 987                 tiqn->sess_err_stats.last_sess_failure_type =
 988                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 989                 tiqn->sess_err_stats.cxn_timeout_errors++;
 990                 atomic_long_inc(&conn->sess->conn_timeout_errors);
 991                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 992         }
 993         }
 994
 995         iscsit_cause_connection_reinstatement(conn, 0);
 996         iscsit_dec_conn_usage_count(conn);
 997 }
 998
 999 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
1000 {
1001         struct iscsi_session *sess = conn->sess;
1002         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1003
1004         spin_lock_bh(&conn->nopin_timer_lock);
1005         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1006                 spin_unlock_bh(&conn->nopin_timer_lock);
1007                 return;
1008         }
1009
1010         mod_timer(&conn->nopin_response_timer,
1011                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
1012         spin_unlock_bh(&conn->nopin_timer_lock);
1013 }
1014
1015 /*
1016  *      Called with conn->nopin_timer_lock held.
1017  */
1018 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
1019 {
1020         struct iscsi_session *sess = conn->sess;
1021         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1022
1023         spin_lock_bh(&conn->nopin_timer_lock);
1024         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
1025                 spin_unlock_bh(&conn->nopin_timer_lock);
1026                 return;
1027         }
1028
1029         init_timer(&conn->nopin_response_timer);
1030         conn->nopin_response_timer.expires =
1031                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
1032         conn->nopin_response_timer.data = (unsigned long)conn;
1033         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
1034         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
1035         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
1036         add_timer(&conn->nopin_response_timer);
1037
1038         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
1039                 " seconds\n", conn->cid, na->nopin_response_timeout);
1040         spin_unlock_bh(&conn->nopin_timer_lock);
1041 }
1042
1043 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
1044 {
1045         spin_lock_bh(&conn->nopin_timer_lock);
1046         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1047                 spin_unlock_bh(&conn->nopin_timer_lock);
1048                 return;
1049         }
1050         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1051         spin_unlock_bh(&conn->nopin_timer_lock);
1052
1053         del_timer_sync(&conn->nopin_response_timer);
1054
1055         spin_lock_bh(&conn->nopin_timer_lock);
1056         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1057         spin_unlock_bh(&conn->nopin_timer_lock);
1058 }
1059
1060 static void iscsit_handle_nopin_timeout(unsigned long data)
1061 {
1062         struct iscsi_conn *conn = (struct iscsi_conn *) data;
1063
1064         iscsit_inc_conn_usage_count(conn);
1065
1066         spin_lock_bh(&conn->nopin_timer_lock);
1067         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1068                 spin_unlock_bh(&conn->nopin_timer_lock);
1069                 iscsit_dec_conn_usage_count(conn);
1070                 return;
1071         }
1072         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1073         spin_unlock_bh(&conn->nopin_timer_lock);
1074
1075         iscsit_add_nopin(conn, 1);
1076         iscsit_dec_conn_usage_count(conn);
1077 }
1078
1079 /*
1080  * Called with conn->nopin_timer_lock held.
1081  */
1082 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1083 {
1084         struct iscsi_session *sess = conn->sess;
1085         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1086         /*
1087         * NOPIN timeout is disabled.
1088          */
1089         if (!na->nopin_timeout)
1090                 return;
1091
1092         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1093                 return;
1094
1095         init_timer(&conn->nopin_timer);
1096         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1097         conn->nopin_timer.data = (unsigned long)conn;
1098         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1099         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1100         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1101         add_timer(&conn->nopin_timer);
1102
1103         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1104                 " interval\n", conn->cid, na->nopin_timeout);
1105 }
1106
1107 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1108 {
1109         struct iscsi_session *sess = conn->sess;
1110         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1111         /*
1112          * NOPIN timeout is disabled..
1113          */
1114         if (!na->nopin_timeout)
1115                 return;
1116
1117         spin_lock_bh(&conn->nopin_timer_lock);
1118         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1119                 spin_unlock_bh(&conn->nopin_timer_lock);
1120                 return;
1121         }
1122
1123         init_timer(&conn->nopin_timer);
1124         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1125         conn->nopin_timer.data = (unsigned long)conn;
1126         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1127         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1128         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1129         add_timer(&conn->nopin_timer);
1130
1131         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1132                         " interval\n", conn->cid, na->nopin_timeout);
1133         spin_unlock_bh(&conn->nopin_timer_lock);
1134 }
1135
1136 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1137 {
1138         spin_lock_bh(&conn->nopin_timer_lock);
1139         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1140                 spin_unlock_bh(&conn->nopin_timer_lock);
1141                 return;
1142         }
1143         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1144         spin_unlock_bh(&conn->nopin_timer_lock);
1145
1146         del_timer_sync(&conn->nopin_timer);
1147
1148         spin_lock_bh(&conn->nopin_timer_lock);
1149         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1150         spin_unlock_bh(&conn->nopin_timer_lock);
1151 }
1152
1153 int iscsit_send_tx_data(
1154         struct iscsi_cmd *cmd,
1155         struct iscsi_conn *conn,
1156         int use_misc)
1157 {
1158         int tx_sent, tx_size;
1159         u32 iov_count;
1160         struct kvec *iov;
1161
1162 send_data:
1163         tx_size = cmd->tx_size;
1164
1165         if (!use_misc) {
1166                 iov = &cmd->iov_data[0];
1167                 iov_count = cmd->iov_data_count;
1168         } else {
1169                 iov = &cmd->iov_misc[0];
1170                 iov_count = cmd->iov_misc_count;
1171         }
1172
1173         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1174         if (tx_size != tx_sent) {
1175                 if (tx_sent == -EAGAIN) {
1176                         pr_err("tx_data() returned -EAGAIN\n");
1177                         goto send_data;
1178                 } else
1179                         return -1;
1180         }
1181         cmd->tx_size = 0;
1182
1183         return 0;
1184 }
1185
1186 int iscsit_fe_sendpage_sg(
1187         struct iscsi_cmd *cmd,
1188         struct iscsi_conn *conn)
1189 {
1190         struct scatterlist *sg = cmd->first_data_sg;
1191         struct kvec iov;
1192         u32 tx_hdr_size, data_len;
1193         u32 offset = cmd->first_data_sg_off;
1194         int tx_sent, iov_off;
1195
1196 send_hdr:
1197         tx_hdr_size = ISCSI_HDR_LEN;
1198         if (conn->conn_ops->HeaderDigest)
1199                 tx_hdr_size += ISCSI_CRC_LEN;
1200
1201         iov.iov_base = cmd->pdu;
1202         iov.iov_len = tx_hdr_size;
1203
1204         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1205         if (tx_hdr_size != tx_sent) {
1206                 if (tx_sent == -EAGAIN) {
1207                         pr_err("tx_data() returned -EAGAIN\n");
1208                         goto send_hdr;
1209                 }
1210                 return -1;
1211         }
1212
1213         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1214         /*
1215          * Set iov_off used by padding and data digest tx_data() calls below
1216          * in order to determine proper offset into cmd->iov_data[]
1217          */
1218         if (conn->conn_ops->DataDigest) {
1219                 data_len -= ISCSI_CRC_LEN;
1220                 if (cmd->padding)
1221                         iov_off = (cmd->iov_data_count - 2);
1222                 else
1223                         iov_off = (cmd->iov_data_count - 1);
1224         } else {
1225                 iov_off = (cmd->iov_data_count - 1);
1226         }
1227         /*
1228          * Perform sendpage() for each page in the scatterlist
1229          */
1230         while (data_len) {
1231                 u32 space = (sg->length - offset);
1232                 u32 sub_len = min_t(u32, data_len, space);
1233 send_pg:
1234                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1235                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1236                 if (tx_sent != sub_len) {
1237                         if (tx_sent == -EAGAIN) {
1238                                 pr_err("tcp_sendpage() returned"
1239                                                 " -EAGAIN\n");
1240                                 goto send_pg;
1241                         }
1242
1243                         pr_err("tcp_sendpage() failure: %d\n",
1244                                         tx_sent);
1245                         return -1;
1246                 }
1247
1248                 data_len -= sub_len;
1249                 offset = 0;
1250                 sg = sg_next(sg);
1251         }
1252
1253 send_padding:
1254         if (cmd->padding) {
1255                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1256
1257                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1258                 if (cmd->padding != tx_sent) {
1259                         if (tx_sent == -EAGAIN) {
1260                                 pr_err("tx_data() returned -EAGAIN\n");
1261                                 goto send_padding;
1262                         }
1263                         return -1;
1264                 }
1265         }
1266
1267 send_datacrc:
1268         if (conn->conn_ops->DataDigest) {
1269                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1270
1271                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1272                 if (ISCSI_CRC_LEN != tx_sent) {
1273                         if (tx_sent == -EAGAIN) {
1274                                 pr_err("tx_data() returned -EAGAIN\n");
1275                                 goto send_datacrc;
1276                         }
1277                         return -1;
1278                 }
1279         }
1280
1281         return 0;
1282 }
1283
1284 /*
1285  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1286  *      back to the Initiator when an expection condition occurs with the
1287  *      errors set in status_class and status_detail.
1288  *
1289  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1290  *      Returns:        0 on success, -1 on error.
1291  */
1292 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1293 {
1294         struct iscsi_login_rsp *hdr;
1295         struct iscsi_login *login = conn->conn_login;
1296
1297         login->login_failed = 1;
1298         iscsit_collect_login_stats(conn, status_class, status_detail);
1299
1300         memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1301
1302         hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1303         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1304         hdr->status_class       = status_class;
1305         hdr->status_detail      = status_detail;
1306         hdr->itt                = conn->login_itt;
1307
1308         return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1309 }
1310
1311 void iscsit_print_session_params(struct iscsi_session *sess)
1312 {
1313         struct iscsi_conn *conn;
1314
1315         pr_debug("-----------------------------[Session Params for"
1316                 " SID: %u]-----------------------------\n", sess->sid);
1317         spin_lock_bh(&sess->conn_lock);
1318         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1319                 iscsi_dump_conn_ops(conn->conn_ops);
1320         spin_unlock_bh(&sess->conn_lock);
1321
1322         iscsi_dump_sess_ops(sess->sess_ops);
1323 }
1324
1325 static int iscsit_do_rx_data(
1326         struct iscsi_conn *conn,
1327         struct iscsi_data_count *count)
1328 {
1329         int data = count->data_length, rx_loop = 0, total_rx = 0;
1330         struct msghdr msg;
1331
1332         if (!conn || !conn->sock || !conn->conn_ops)
1333                 return -1;
1334
1335         memset(&msg, 0, sizeof(struct msghdr));
1336         iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC,
1337                       count->iov, count->iov_count, data);
1338
1339         while (total_rx < data) {
1340                 rx_loop = sock_recvmsg(conn->sock, &msg,
1341                                       (data - total_rx), MSG_WAITALL);
1342                 if (rx_loop <= 0) {
1343                         pr_debug("rx_loop: %d total_rx: %d\n",
1344                                 rx_loop, total_rx);
1345                         return rx_loop;
1346                 }
1347                 total_rx += rx_loop;
1348                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1349                                 rx_loop, total_rx, data);
1350         }
1351
1352         return total_rx;
1353 }
1354
1355 static int iscsit_do_tx_data(
1356         struct iscsi_conn *conn,
1357         struct iscsi_data_count *count)
1358 {
1359         int ret, iov_len;
1360         struct kvec *iov_p;
1361         struct msghdr msg;
1362
1363         if (!conn || !conn->sock || !conn->conn_ops)
1364                 return -1;
1365
1366         if (count->data_length <= 0) {
1367                 pr_err("Data length is: %d\n", count->data_length);
1368                 return -1;
1369         }
1370
1371         memset(&msg, 0, sizeof(struct msghdr));
1372
1373         iov_p = count->iov;
1374         iov_len = count->iov_count;
1375
1376         ret = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1377                              count->data_length);
1378         if (ret != count->data_length) {
1379                 pr_err("Unexpected ret: %d send data %d\n",
1380                        ret, count->data_length);
1381                 return -EPIPE;
1382         }
1383         pr_debug("ret: %d, sent data: %d\n", ret, count->data_length);
1384
1385         return ret;
1386 }
1387
1388 int rx_data(
1389         struct iscsi_conn *conn,
1390         struct kvec *iov,
1391         int iov_count,
1392         int data)
1393 {
1394         struct iscsi_data_count c;
1395
1396         if (!conn || !conn->sock || !conn->conn_ops)
1397                 return -1;
1398
1399         memset(&c, 0, sizeof(struct iscsi_data_count));
1400         c.iov = iov;
1401         c.iov_count = iov_count;
1402         c.data_length = data;
1403         c.type = ISCSI_RX_DATA;
1404
1405         return iscsit_do_rx_data(conn, &c);
1406 }
1407
1408 int tx_data(
1409         struct iscsi_conn *conn,
1410         struct kvec *iov,
1411         int iov_count,
1412         int data)
1413 {
1414         struct iscsi_data_count c;
1415
1416         if (!conn || !conn->sock || !conn->conn_ops)
1417                 return -1;
1418
1419         memset(&c, 0, sizeof(struct iscsi_data_count));
1420         c.iov = iov;
1421         c.iov_count = iov_count;
1422         c.data_length = data;
1423         c.type = ISCSI_TX_DATA;
1424
1425         return iscsit_do_tx_data(conn, &c);
1426 }
1427
1428 void iscsit_collect_login_stats(
1429         struct iscsi_conn *conn,
1430         u8 status_class,
1431         u8 status_detail)
1432 {
1433         struct iscsi_param *intrname = NULL;
1434         struct iscsi_tiqn *tiqn;
1435         struct iscsi_login_stats *ls;
1436
1437         tiqn = iscsit_snmp_get_tiqn(conn);
1438         if (!tiqn)
1439                 return;
1440
1441         ls = &tiqn->login_stats;
1442
1443         spin_lock(&ls->lock);
1444         if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1445             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1446                 /* We already have the failure info for this login */
1447                 spin_unlock(&ls->lock);
1448                 return;
1449         }
1450
1451         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1452                 ls->accepts++;
1453         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1454                 ls->redirects++;
1455                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1456         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1457                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1458                 ls->authenticate_fails++;
1459                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1460         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1461                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1462                 ls->authorize_fails++;
1463                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1464         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1465                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1466                 ls->negotiate_fails++;
1467                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1468         } else {
1469                 ls->other_fails++;
1470                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1471         }
1472
1473         /* Save initiator name, ip address and time, if it is a failed login */
1474         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1475                 if (conn->param_list)
1476                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1477                                                              conn->param_list);
1478                 strlcpy(ls->last_intr_fail_name,
1479                        (intrname ? intrname->value : "Unknown"),
1480                        sizeof(ls->last_intr_fail_name));
1481
1482                 ls->last_intr_fail_ip_family = conn->login_family;
1483
1484                 snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1485                                 "%s", conn->login_ip);
1486                 ls->last_fail_time = get_jiffies_64();
1487         }
1488
1489         spin_unlock(&ls->lock);
1490 }
1491
1492 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1493 {
1494         struct iscsi_portal_group *tpg;
1495
1496         if (!conn || !conn->sess)
1497                 return NULL;
1498
1499         tpg = conn->sess->tpg;
1500         if (!tpg)
1501                 return NULL;
1502
1503         if (!tpg->tpg_tiqn)
1504                 return NULL;
1505
1506         return tpg->tpg_tiqn;
1507 }