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->init_task_tag == init_task_tag) {
 404                         spin_unlock_bh(&conn->cmd_lock);
 405                         return cmd;
 406                 }
 407         }
 408         spin_unlock_bh(&conn->cmd_lock);
 409
 410         pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 411                         " dumping payload\n", init_task_tag, conn->cid);
 412         if (length)
 413                 iscsit_dump_data_payload(conn, length, 1);
 414
 415         return NULL;
 416 }
 417
 418 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 419         struct iscsi_conn *conn,
 420         u32 targ_xfer_tag)
 421 {
 422         struct iscsi_cmd *cmd = NULL;
 423
 424         spin_lock_bh(&conn->cmd_lock);
 425         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 426                 if (cmd->targ_xfer_tag == targ_xfer_tag) {
 427                         spin_unlock_bh(&conn->cmd_lock);
 428                         return cmd;
 429                 }
 430         }
 431         spin_unlock_bh(&conn->cmd_lock);
 432
 433         pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 434                         targ_xfer_tag, conn->cid);
 435         return NULL;
 436 }
 437
 438 int iscsit_find_cmd_for_recovery(
 439         struct iscsi_session *sess,
 440         struct iscsi_cmd **cmd_ptr,
 441         struct iscsi_conn_recovery **cr_ptr,
 442         itt_t init_task_tag)
 443 {
 444         struct iscsi_cmd *cmd = NULL;
 445         struct iscsi_conn_recovery *cr;
 446         /*
 447          * Scan through the inactive connection recovery list's command list.
 448          * If init_task_tag matches the command is still alligent.
 449          */
 450         spin_lock(&sess->cr_i_lock);
 451         list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 452                 spin_lock(&cr->conn_recovery_cmd_lock);
 453                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 454                         if (cmd->init_task_tag == init_task_tag) {
 455                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 456                                 spin_unlock(&sess->cr_i_lock);
 457
 458                                 *cr_ptr = cr;
 459                                 *cmd_ptr = cmd;
 460                                 return -2;
 461                         }
 462                 }
 463                 spin_unlock(&cr->conn_recovery_cmd_lock);
 464         }
 465         spin_unlock(&sess->cr_i_lock);
 466         /*
 467          * Scan through the active connection recovery list's command list.
 468          * If init_task_tag matches the command is ready to be reassigned.
 469          */
 470         spin_lock(&sess->cr_a_lock);
 471         list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 472                 spin_lock(&cr->conn_recovery_cmd_lock);
 473                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 474                         if (cmd->init_task_tag == init_task_tag) {
 475                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 476                                 spin_unlock(&sess->cr_a_lock);
 477
 478                                 *cr_ptr = cr;
 479                                 *cmd_ptr = cmd;
 480                                 return 0;
 481                         }
 482                 }
 483                 spin_unlock(&cr->conn_recovery_cmd_lock);
 484         }
 485         spin_unlock(&sess->cr_a_lock);
 486
 487         return -1;
 488 }
 489
 490 void iscsit_add_cmd_to_immediate_queue(
 491         struct iscsi_cmd *cmd,
 492         struct iscsi_conn *conn,
 493         u8 state)
 494 {
 495         struct iscsi_queue_req *qr;
 496
 497         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 498         if (!qr) {
 499                 pr_err("Unable to allocate memory for"
 500                                 " struct iscsi_queue_req\n");
 501                 return;
 502         }
 503         INIT_LIST_HEAD(&qr->qr_list);
 504         qr->cmd = cmd;
 505         qr->state = state;
 506
 507         spin_lock_bh(&conn->immed_queue_lock);
 508         list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 509         atomic_inc(&cmd->immed_queue_count);
 510         atomic_set(&conn->check_immediate_queue, 1);
 511         spin_unlock_bh(&conn->immed_queue_lock);
 512
 513         wake_up(&conn->queues_wq);
 514 }
 515
 516 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 517 {
 518         struct iscsi_queue_req *qr;
 519
 520         spin_lock_bh(&conn->immed_queue_lock);
 521         if (list_empty(&conn->immed_queue_list)) {
 522                 spin_unlock_bh(&conn->immed_queue_lock);
 523                 return NULL;
 524         }
 525         qr = list_first_entry(&conn->immed_queue_list,
 526                               struct iscsi_queue_req, qr_list);
 527
 528         list_del(&qr->qr_list);
 529         if (qr->cmd)
 530                 atomic_dec(&qr->cmd->immed_queue_count);
 531         spin_unlock_bh(&conn->immed_queue_lock);
 532
 533         return qr;
 534 }
 535
 536 static void iscsit_remove_cmd_from_immediate_queue(
 537         struct iscsi_cmd *cmd,
 538         struct iscsi_conn *conn)
 539 {
 540         struct iscsi_queue_req *qr, *qr_tmp;
 541
 542         spin_lock_bh(&conn->immed_queue_lock);
 543         if (!atomic_read(&cmd->immed_queue_count)) {
 544                 spin_unlock_bh(&conn->immed_queue_lock);
 545                 return;
 546         }
 547
 548         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 549                 if (qr->cmd != cmd)
 550                         continue;
 551
 552                 atomic_dec(&qr->cmd->immed_queue_count);
 553                 list_del(&qr->qr_list);
 554                 kmem_cache_free(lio_qr_cache, qr);
 555         }
 556         spin_unlock_bh(&conn->immed_queue_lock);
 557
 558         if (atomic_read(&cmd->immed_queue_count)) {
 559                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 560                         cmd->init_task_tag,
 561                         atomic_read(&cmd->immed_queue_count));
 562         }
 563 }
 564
 565 void iscsit_add_cmd_to_response_queue(
 566         struct iscsi_cmd *cmd,
 567         struct iscsi_conn *conn,
 568         u8 state)
 569 {
 570         struct iscsi_queue_req *qr;
 571
 572         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 573         if (!qr) {
 574                 pr_err("Unable to allocate memory for"
 575                         " struct iscsi_queue_req\n");
 576                 return;
 577         }
 578         INIT_LIST_HEAD(&qr->qr_list);
 579         qr->cmd = cmd;
 580         qr->state = state;
 581
 582         spin_lock_bh(&conn->response_queue_lock);
 583         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 584         atomic_inc(&cmd->response_queue_count);
 585         spin_unlock_bh(&conn->response_queue_lock);
 586
 587         wake_up(&conn->queues_wq);
 588 }
 589
 590 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 591 {
 592         struct iscsi_queue_req *qr;
 593
 594         spin_lock_bh(&conn->response_queue_lock);
 595         if (list_empty(&conn->response_queue_list)) {
 596                 spin_unlock_bh(&conn->response_queue_lock);
 597                 return NULL;
 598         }
 599
 600         qr = list_first_entry(&conn->response_queue_list,
 601                               struct iscsi_queue_req, qr_list);
 602
 603         list_del(&qr->qr_list);
 604         if (qr->cmd)
 605                 atomic_dec(&qr->cmd->response_queue_count);
 606         spin_unlock_bh(&conn->response_queue_lock);
 607
 608         return qr;
 609 }
 610
 611 static void iscsit_remove_cmd_from_response_queue(
 612         struct iscsi_cmd *cmd,
 613         struct iscsi_conn *conn)
 614 {
 615         struct iscsi_queue_req *qr, *qr_tmp;
 616
 617         spin_lock_bh(&conn->response_queue_lock);
 618         if (!atomic_read(&cmd->response_queue_count)) {
 619                 spin_unlock_bh(&conn->response_queue_lock);
 620                 return;
 621         }
 622
 623         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 624                                 qr_list) {
 625                 if (qr->cmd != cmd)
 626                         continue;
 627
 628                 atomic_dec(&qr->cmd->response_queue_count);
 629                 list_del(&qr->qr_list);
 630                 kmem_cache_free(lio_qr_cache, qr);
 631         }
 632         spin_unlock_bh(&conn->response_queue_lock);
 633
 634         if (atomic_read(&cmd->response_queue_count)) {
 635                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 636                         cmd->init_task_tag,
 637                         atomic_read(&cmd->response_queue_count));
 638         }
 639 }
 640
 641 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 642 {
 643         bool empty;
 644
 645         spin_lock_bh(&conn->immed_queue_lock);
 646         empty = list_empty(&conn->immed_queue_list);
 647         spin_unlock_bh(&conn->immed_queue_lock);
 648
 649         if (!empty)
 650                 return empty;
 651
 652         spin_lock_bh(&conn->response_queue_lock);
 653         empty = list_empty(&conn->response_queue_list);
 654         spin_unlock_bh(&conn->response_queue_lock);
 655
 656         return empty;
 657 }
 658
 659 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 660 {
 661         struct iscsi_queue_req *qr, *qr_tmp;
 662
 663         spin_lock_bh(&conn->immed_queue_lock);
 664         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 665                 list_del(&qr->qr_list);
 666                 if (qr->cmd)
 667                         atomic_dec(&qr->cmd->immed_queue_count);
 668
 669                 kmem_cache_free(lio_qr_cache, qr);
 670         }
 671         spin_unlock_bh(&conn->immed_queue_lock);
 672
 673         spin_lock_bh(&conn->response_queue_lock);
 674         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 675                         qr_list) {
 676                 list_del(&qr->qr_list);
 677                 if (qr->cmd)
 678                         atomic_dec(&qr->cmd->response_queue_count);
 679
 680                 kmem_cache_free(lio_qr_cache, qr);
 681         }
 682         spin_unlock_bh(&conn->response_queue_lock);
 683 }
 684
 685 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 686 {
 687         struct iscsi_session *sess;
 688         struct se_cmd *se_cmd = &cmd->se_cmd;
 689
 690         if (cmd->conn)
 691                 sess = cmd->conn->sess;
 692         else
 693                 sess = cmd->sess;
 694
 695         BUG_ON(!sess || !sess->se_sess);
 696
 697         kfree(cmd->buf_ptr);
 698         kfree(cmd->pdu_list);
 699         kfree(cmd->seq_list);
 700         kfree(cmd->tmr_req);
 701         kfree(cmd->iov_data);
 702         kfree(cmd->text_in_ptr);
 703
 704         percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 705 }
 706 EXPORT_SYMBOL(iscsit_release_cmd);
 707
 708 void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool scsi_cmd,
 709                        bool check_queues)
 710 {
 711         struct iscsi_conn *conn = cmd->conn;
 712
 713         if (scsi_cmd) {
 714                 if (cmd->data_direction == DMA_TO_DEVICE) {
 715                         iscsit_stop_dataout_timer(cmd);
 716                         iscsit_free_r2ts_from_list(cmd);
 717                 }
 718                 if (cmd->data_direction == DMA_FROM_DEVICE)
 719                         iscsit_free_all_datain_reqs(cmd);
 720         }
 721
 722         if (conn && check_queues) {
 723                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 724                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 725         }
 726 }
 727
 728 void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 729 {
 730         struct se_cmd *se_cmd = NULL;
 731         int rc;
 732         /*
 733          * Determine if a struct se_cmd is associated with
 734          * this struct iscsi_cmd.
 735          */
 736         switch (cmd->iscsi_opcode) {
 737         case ISCSI_OP_SCSI_CMD:
 738                 se_cmd = &cmd->se_cmd;
 739                 __iscsit_free_cmd(cmd, true, shutdown);
 740                 /*
 741                  * Fallthrough
 742                  */
 743         case ISCSI_OP_SCSI_TMFUNC:
 744                 rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 745                 if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
 746                         __iscsit_free_cmd(cmd, true, shutdown);
 747                         target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 748                 }
 749                 break;
 750         case ISCSI_OP_REJECT:
 751                 /*
 752                  * Handle special case for REJECT when iscsi_add_reject*() has
 753                  * overwritten the original iscsi_opcode assignment, and the
 754                  * associated cmd->se_cmd needs to be released.
 755                  */
 756                 if (cmd->se_cmd.se_tfo != NULL) {
 757                         se_cmd = &cmd->se_cmd;
 758                         __iscsit_free_cmd(cmd, true, shutdown);
 759
 760                         rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 761                         if (!rc && shutdown && se_cmd->se_sess) {
 762                                 __iscsit_free_cmd(cmd, true, shutdown);
 763                                 target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 764                         }
 765                         break;
 766                 }
 767                 /* Fall-through */
 768         default:
 769                 __iscsit_free_cmd(cmd, false, shutdown);
 770                 iscsit_release_cmd(cmd);
 771                 break;
 772         }
 773 }
 774
 775 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 776 {
 777         spin_lock_bh(&sess->session_usage_lock);
 778         if (sess->session_usage_count != 0) {
 779                 sess->session_waiting_on_uc = 1;
 780                 spin_unlock_bh(&sess->session_usage_lock);
 781                 if (in_interrupt())
 782                         return 2;
 783
 784                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 785                 return 1;
 786         }
 787         spin_unlock_bh(&sess->session_usage_lock);
 788
 789         return 0;
 790 }
 791
 792 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 793 {
 794         spin_lock_bh(&sess->session_usage_lock);
 795         sess->session_usage_count--;
 796
 797         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 798                 complete(&sess->session_waiting_on_uc_comp);
 799
 800         spin_unlock_bh(&sess->session_usage_lock);
 801 }
 802
 803 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 804 {
 805         spin_lock_bh(&sess->session_usage_lock);
 806         sess->session_usage_count++;
 807         spin_unlock_bh(&sess->session_usage_lock);
 808 }
 809
 810 /*
 811  *      Setup conn->if_marker and conn->of_marker values based upon
 812  *      the initial marker-less interval. (see iSCSI v19 A.2)
 813  */
 814 int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 815 {
 816         int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 817         /*
 818          * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 819          */
 820         u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 821         u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 822
 823         if (conn->conn_ops->OFMarker) {
 824                 /*
 825                  * Account for the first Login Command received not
 826                  * via iscsi_recv_msg().
 827                  */
 828                 conn->of_marker += ISCSI_HDR_LEN;
 829                 if (conn->of_marker <= OFMarkInt) {
 830                         conn->of_marker = (OFMarkInt - conn->of_marker);
 831                 } else {
 832                         login_ofmarker_count = (conn->of_marker / OFMarkInt);
 833                         next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 834                                         (login_ofmarker_count * MARKER_SIZE);
 835                         conn->of_marker = (next_marker - conn->of_marker);
 836                 }
 837                 conn->of_marker_offset = 0;
 838                 pr_debug("Setting OFMarker value to %u based on Initial"
 839                         " Markerless Interval.\n", conn->of_marker);
 840         }
 841
 842         if (conn->conn_ops->IFMarker) {
 843                 if (conn->if_marker <= IFMarkInt) {
 844                         conn->if_marker = (IFMarkInt - conn->if_marker);
 845                 } else {
 846                         login_ifmarker_count = (conn->if_marker / IFMarkInt);
 847                         next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 848                                         (login_ifmarker_count * MARKER_SIZE);
 849                         conn->if_marker = (next_marker - conn->if_marker);
 850                 }
 851                 pr_debug("Setting IFMarker value to %u based on Initial"
 852                         " Markerless Interval.\n", conn->if_marker);
 853         }
 854
 855         return 0;
 856 }
 857
 858 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 859 {
 860         struct iscsi_conn *conn;
 861
 862         spin_lock_bh(&sess->conn_lock);
 863         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 864                 if ((conn->cid == cid) &&
 865                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 866                         iscsit_inc_conn_usage_count(conn);
 867                         spin_unlock_bh(&sess->conn_lock);
 868                         return conn;
 869                 }
 870         }
 871         spin_unlock_bh(&sess->conn_lock);
 872
 873         return NULL;
 874 }
 875
 876 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 877 {
 878         struct iscsi_conn *conn;
 879
 880         spin_lock_bh(&sess->conn_lock);
 881         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 882                 if (conn->cid == cid) {
 883                         iscsit_inc_conn_usage_count(conn);
 884                         spin_lock(&conn->state_lock);
 885                         atomic_set(&conn->connection_wait_rcfr, 1);
 886                         spin_unlock(&conn->state_lock);
 887                         spin_unlock_bh(&sess->conn_lock);
 888                         return conn;
 889                 }
 890         }
 891         spin_unlock_bh(&sess->conn_lock);
 892
 893         return NULL;
 894 }
 895
 896 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 897 {
 898         spin_lock_bh(&conn->conn_usage_lock);
 899         if (conn->conn_usage_count != 0) {
 900                 conn->conn_waiting_on_uc = 1;
 901                 spin_unlock_bh(&conn->conn_usage_lock);
 902
 903                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 904                 return;
 905         }
 906         spin_unlock_bh(&conn->conn_usage_lock);
 907 }
 908
 909 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 910 {
 911         spin_lock_bh(&conn->conn_usage_lock);
 912         conn->conn_usage_count--;
 913
 914         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 915                 complete(&conn->conn_waiting_on_uc_comp);
 916
 917         spin_unlock_bh(&conn->conn_usage_lock);
 918 }
 919
 920 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 921 {
 922         spin_lock_bh(&conn->conn_usage_lock);
 923         conn->conn_usage_count++;
 924         spin_unlock_bh(&conn->conn_usage_lock);
 925 }
 926
 927 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 928 {
 929         u8 state;
 930         struct iscsi_cmd *cmd;
 931
 932         cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
 933         if (!cmd)
 934                 return -1;
 935
 936         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 937         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 938                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 939         cmd->init_task_tag = RESERVED_ITT;
 940         spin_lock_bh(&conn->sess->ttt_lock);
 941         cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
 942                         0xFFFFFFFF;
 943         if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
 944                 cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
 945         spin_unlock_bh(&conn->sess->ttt_lock);
 946
 947         spin_lock_bh(&conn->cmd_lock);
 948         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 949         spin_unlock_bh(&conn->cmd_lock);
 950
 951         if (want_response)
 952                 iscsit_start_nopin_response_timer(conn);
 953         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 954
 955         return 0;
 956 }
 957
 958 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 959 {
 960         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 961
 962         iscsit_inc_conn_usage_count(conn);
 963
 964         spin_lock_bh(&conn->nopin_timer_lock);
 965         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 966                 spin_unlock_bh(&conn->nopin_timer_lock);
 967                 iscsit_dec_conn_usage_count(conn);
 968                 return;
 969         }
 970
 971         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 972                 " SID: %u, failing connection.\n", conn->cid,
 973                         conn->sess->sid);
 974         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 975         spin_unlock_bh(&conn->nopin_timer_lock);
 976
 977         {
 978         struct iscsi_portal_group *tpg = conn->sess->tpg;
 979         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 980
 981         if (tiqn) {
 982                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 983                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 984                                 conn->sess->sess_ops->InitiatorName);
 985                 tiqn->sess_err_stats.last_sess_failure_type =
 986                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 987                 tiqn->sess_err_stats.cxn_timeout_errors++;
 988                 atomic_long_inc(&conn->sess->conn_timeout_errors);
 989                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 990         }
 991         }
 992
 993         iscsit_cause_connection_reinstatement(conn, 0);
 994         iscsit_dec_conn_usage_count(conn);
 995 }
 996
 997 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 998 {
 999         struct iscsi_session *sess = conn->sess;
1000         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1001
1002         spin_lock_bh(&conn->nopin_timer_lock);
1003         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1004                 spin_unlock_bh(&conn->nopin_timer_lock);
1005                 return;
1006         }
1007
1008         mod_timer(&conn->nopin_response_timer,
1009                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
1010         spin_unlock_bh(&conn->nopin_timer_lock);
1011 }
1012
1013 /*
1014  *      Called with conn->nopin_timer_lock held.
1015  */
1016 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
1017 {
1018         struct iscsi_session *sess = conn->sess;
1019         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1020
1021         spin_lock_bh(&conn->nopin_timer_lock);
1022         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
1023                 spin_unlock_bh(&conn->nopin_timer_lock);
1024                 return;
1025         }
1026
1027         init_timer(&conn->nopin_response_timer);
1028         conn->nopin_response_timer.expires =
1029                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
1030         conn->nopin_response_timer.data = (unsigned long)conn;
1031         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
1032         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
1033         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
1034         add_timer(&conn->nopin_response_timer);
1035
1036         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
1037                 " seconds\n", conn->cid, na->nopin_response_timeout);
1038         spin_unlock_bh(&conn->nopin_timer_lock);
1039 }
1040
1041 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
1042 {
1043         spin_lock_bh(&conn->nopin_timer_lock);
1044         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1045                 spin_unlock_bh(&conn->nopin_timer_lock);
1046                 return;
1047         }
1048         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1049         spin_unlock_bh(&conn->nopin_timer_lock);
1050
1051         del_timer_sync(&conn->nopin_response_timer);
1052
1053         spin_lock_bh(&conn->nopin_timer_lock);
1054         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1055         spin_unlock_bh(&conn->nopin_timer_lock);
1056 }
1057
1058 static void iscsit_handle_nopin_timeout(unsigned long data)
1059 {
1060         struct iscsi_conn *conn = (struct iscsi_conn *) data;
1061
1062         iscsit_inc_conn_usage_count(conn);
1063
1064         spin_lock_bh(&conn->nopin_timer_lock);
1065         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1066                 spin_unlock_bh(&conn->nopin_timer_lock);
1067                 iscsit_dec_conn_usage_count(conn);
1068                 return;
1069         }
1070         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1071         spin_unlock_bh(&conn->nopin_timer_lock);
1072
1073         iscsit_add_nopin(conn, 1);
1074         iscsit_dec_conn_usage_count(conn);
1075 }
1076
1077 /*
1078  * Called with conn->nopin_timer_lock held.
1079  */
1080 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1081 {
1082         struct iscsi_session *sess = conn->sess;
1083         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1084         /*
1085         * NOPIN timeout is disabled.
1086          */
1087         if (!na->nopin_timeout)
1088                 return;
1089
1090         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1091                 return;
1092
1093         init_timer(&conn->nopin_timer);
1094         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1095         conn->nopin_timer.data = (unsigned long)conn;
1096         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1097         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1098         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1099         add_timer(&conn->nopin_timer);
1100
1101         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1102                 " interval\n", conn->cid, na->nopin_timeout);
1103 }
1104
1105 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1106 {
1107         struct iscsi_session *sess = conn->sess;
1108         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1109         /*
1110          * NOPIN timeout is disabled..
1111          */
1112         if (!na->nopin_timeout)
1113                 return;
1114
1115         spin_lock_bh(&conn->nopin_timer_lock);
1116         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1117                 spin_unlock_bh(&conn->nopin_timer_lock);
1118                 return;
1119         }
1120
1121         init_timer(&conn->nopin_timer);
1122         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1123         conn->nopin_timer.data = (unsigned long)conn;
1124         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1125         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1126         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1127         add_timer(&conn->nopin_timer);
1128
1129         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1130                         " interval\n", conn->cid, na->nopin_timeout);
1131         spin_unlock_bh(&conn->nopin_timer_lock);
1132 }
1133
1134 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1135 {
1136         spin_lock_bh(&conn->nopin_timer_lock);
1137         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1138                 spin_unlock_bh(&conn->nopin_timer_lock);
1139                 return;
1140         }
1141         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1142         spin_unlock_bh(&conn->nopin_timer_lock);
1143
1144         del_timer_sync(&conn->nopin_timer);
1145
1146         spin_lock_bh(&conn->nopin_timer_lock);
1147         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1148         spin_unlock_bh(&conn->nopin_timer_lock);
1149 }
1150
1151 int iscsit_send_tx_data(
1152         struct iscsi_cmd *cmd,
1153         struct iscsi_conn *conn,
1154         int use_misc)
1155 {
1156         int tx_sent, tx_size;
1157         u32 iov_count;
1158         struct kvec *iov;
1159
1160 send_data:
1161         tx_size = cmd->tx_size;
1162
1163         if (!use_misc) {
1164                 iov = &cmd->iov_data[0];
1165                 iov_count = cmd->iov_data_count;
1166         } else {
1167                 iov = &cmd->iov_misc[0];
1168                 iov_count = cmd->iov_misc_count;
1169         }
1170
1171         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1172         if (tx_size != tx_sent) {
1173                 if (tx_sent == -EAGAIN) {
1174                         pr_err("tx_data() returned -EAGAIN\n");
1175                         goto send_data;
1176                 } else
1177                         return -1;
1178         }
1179         cmd->tx_size = 0;
1180
1181         return 0;
1182 }
1183
1184 int iscsit_fe_sendpage_sg(
1185         struct iscsi_cmd *cmd,
1186         struct iscsi_conn *conn)
1187 {
1188         struct scatterlist *sg = cmd->first_data_sg;
1189         struct kvec iov;
1190         u32 tx_hdr_size, data_len;
1191         u32 offset = cmd->first_data_sg_off;
1192         int tx_sent, iov_off;
1193
1194 send_hdr:
1195         tx_hdr_size = ISCSI_HDR_LEN;
1196         if (conn->conn_ops->HeaderDigest)
1197                 tx_hdr_size += ISCSI_CRC_LEN;
1198
1199         iov.iov_base = cmd->pdu;
1200         iov.iov_len = tx_hdr_size;
1201
1202         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1203         if (tx_hdr_size != tx_sent) {
1204                 if (tx_sent == -EAGAIN) {
1205                         pr_err("tx_data() returned -EAGAIN\n");
1206                         goto send_hdr;
1207                 }
1208                 return -1;
1209         }
1210
1211         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1212         /*
1213          * Set iov_off used by padding and data digest tx_data() calls below
1214          * in order to determine proper offset into cmd->iov_data[]
1215          */
1216         if (conn->conn_ops->DataDigest) {
1217                 data_len -= ISCSI_CRC_LEN;
1218                 if (cmd->padding)
1219                         iov_off = (cmd->iov_data_count - 2);
1220                 else
1221                         iov_off = (cmd->iov_data_count - 1);
1222         } else {
1223                 iov_off = (cmd->iov_data_count - 1);
1224         }
1225         /*
1226          * Perform sendpage() for each page in the scatterlist
1227          */
1228         while (data_len) {
1229                 u32 space = (sg->length - offset);
1230                 u32 sub_len = min_t(u32, data_len, space);
1231 send_pg:
1232                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1233                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1234                 if (tx_sent != sub_len) {
1235                         if (tx_sent == -EAGAIN) {
1236                                 pr_err("tcp_sendpage() returned"
1237                                                 " -EAGAIN\n");
1238                                 goto send_pg;
1239                         }
1240
1241                         pr_err("tcp_sendpage() failure: %d\n",
1242                                         tx_sent);
1243                         return -1;
1244                 }
1245
1246                 data_len -= sub_len;
1247                 offset = 0;
1248                 sg = sg_next(sg);
1249         }
1250
1251 send_padding:
1252         if (cmd->padding) {
1253                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1254
1255                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1256                 if (cmd->padding != tx_sent) {
1257                         if (tx_sent == -EAGAIN) {
1258                                 pr_err("tx_data() returned -EAGAIN\n");
1259                                 goto send_padding;
1260                         }
1261                         return -1;
1262                 }
1263         }
1264
1265 send_datacrc:
1266         if (conn->conn_ops->DataDigest) {
1267                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1268
1269                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1270                 if (ISCSI_CRC_LEN != tx_sent) {
1271                         if (tx_sent == -EAGAIN) {
1272                                 pr_err("tx_data() returned -EAGAIN\n");
1273                                 goto send_datacrc;
1274                         }
1275                         return -1;
1276                 }
1277         }
1278
1279         return 0;
1280 }
1281
1282 /*
1283  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1284  *      back to the Initiator when an expection condition occurs with the
1285  *      errors set in status_class and status_detail.
1286  *
1287  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1288  *      Returns:        0 on success, -1 on error.
1289  */
1290 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1291 {
1292         struct iscsi_login_rsp *hdr;
1293         struct iscsi_login *login = conn->conn_login;
1294
1295         login->login_failed = 1;
1296         iscsit_collect_login_stats(conn, status_class, status_detail);
1297
1298         memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1299
1300         hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1301         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1302         hdr->status_class       = status_class;
1303         hdr->status_detail      = status_detail;
1304         hdr->itt                = conn->login_itt;
1305
1306         return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1307 }
1308
1309 void iscsit_print_session_params(struct iscsi_session *sess)
1310 {
1311         struct iscsi_conn *conn;
1312
1313         pr_debug("-----------------------------[Session Params for"
1314                 " SID: %u]-----------------------------\n", sess->sid);
1315         spin_lock_bh(&sess->conn_lock);
1316         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1317                 iscsi_dump_conn_ops(conn->conn_ops);
1318         spin_unlock_bh(&sess->conn_lock);
1319
1320         iscsi_dump_sess_ops(sess->sess_ops);
1321 }
1322
1323 static int iscsit_do_rx_data(
1324         struct iscsi_conn *conn,
1325         struct iscsi_data_count *count)
1326 {
1327         int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
1328         struct kvec *iov_p;
1329         struct msghdr msg;
1330
1331         if (!conn || !conn->sock || !conn->conn_ops)
1332                 return -1;
1333
1334         memset(&msg, 0, sizeof(struct msghdr));
1335
1336         iov_p = count->iov;
1337         iov_len = count->iov_count;
1338
1339         while (total_rx < data) {
1340                 rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
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 data = count->data_length, total_tx = 0, tx_loop = 0, 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 (data <= 0) {
1367                 pr_err("Data length is: %d\n", data);
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         while (total_tx < data) {
1377                 tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1378                                         (data - total_tx));
1379                 if (tx_loop <= 0) {
1380                         pr_debug("tx_loop: %d total_tx %d\n",
1381                                 tx_loop, total_tx);
1382                         return tx_loop;
1383                 }
1384                 total_tx += tx_loop;
1385                 pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1386                                         tx_loop, total_tx, data);
1387         }
1388
1389         return total_tx;
1390 }
1391
1392 int rx_data(
1393         struct iscsi_conn *conn,
1394         struct kvec *iov,
1395         int iov_count,
1396         int data)
1397 {
1398         struct iscsi_data_count c;
1399
1400         if (!conn || !conn->sock || !conn->conn_ops)
1401                 return -1;
1402
1403         memset(&c, 0, sizeof(struct iscsi_data_count));
1404         c.iov = iov;
1405         c.iov_count = iov_count;
1406         c.data_length = data;
1407         c.type = ISCSI_RX_DATA;
1408
1409         return iscsit_do_rx_data(conn, &c);
1410 }
1411
1412 int tx_data(
1413         struct iscsi_conn *conn,
1414         struct kvec *iov,
1415         int iov_count,
1416         int data)
1417 {
1418         struct iscsi_data_count c;
1419
1420         if (!conn || !conn->sock || !conn->conn_ops)
1421                 return -1;
1422
1423         memset(&c, 0, sizeof(struct iscsi_data_count));
1424         c.iov = iov;
1425         c.iov_count = iov_count;
1426         c.data_length = data;
1427         c.type = ISCSI_TX_DATA;
1428
1429         return iscsit_do_tx_data(conn, &c);
1430 }
1431
1432 void iscsit_collect_login_stats(
1433         struct iscsi_conn *conn,
1434         u8 status_class,
1435         u8 status_detail)
1436 {
1437         struct iscsi_param *intrname = NULL;
1438         struct iscsi_tiqn *tiqn;
1439         struct iscsi_login_stats *ls;
1440
1441         tiqn = iscsit_snmp_get_tiqn(conn);
1442         if (!tiqn)
1443                 return;
1444
1445         ls = &tiqn->login_stats;
1446
1447         spin_lock(&ls->lock);
1448         if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1449             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1450                 /* We already have the failure info for this login */
1451                 spin_unlock(&ls->lock);
1452                 return;
1453         }
1454
1455         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1456                 ls->accepts++;
1457         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1458                 ls->redirects++;
1459                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1460         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1461                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1462                 ls->authenticate_fails++;
1463                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1464         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1465                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1466                 ls->authorize_fails++;
1467                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1468         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1469                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1470                 ls->negotiate_fails++;
1471                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1472         } else {
1473                 ls->other_fails++;
1474                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1475         }
1476
1477         /* Save initiator name, ip address and time, if it is a failed login */
1478         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1479                 if (conn->param_list)
1480                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1481                                                              conn->param_list);
1482                 strcpy(ls->last_intr_fail_name,
1483                        (intrname ? intrname->value : "Unknown"));
1484
1485                 ls->last_intr_fail_ip_family = conn->login_family;
1486
1487                 snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1488                                 "%s", conn->login_ip);
1489                 ls->last_fail_time = get_jiffies_64();
1490         }
1491
1492         spin_unlock(&ls->lock);
1493 }
1494
1495 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1496 {
1497         struct iscsi_portal_group *tpg;
1498
1499         if (!conn || !conn->sess)
1500                 return NULL;
1501
1502         tpg = conn->sess->tpg;
1503         if (!tpg)
1504                 return NULL;
1505
1506         if (!tpg->tpg_tiqn)
1507                 return NULL;
1508
1509         return tpg->tpg_tiqn;
1510 }