drivers/target/iscsi/iscsi_target_util.c

   1 /*******************************************************************************
   2  * This file contains the iSCSI Target specific utility functions.
   3  *
   4  * (c) Copyright 2007-2013 Datera, Inc.
   5  *
   6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  ******************************************************************************/
  18
  19 #include <linux/list.h>
  20 #include <linux/percpu_ida.h>
  21 #include <net/ipv6.h>         /* ipv6_addr_equal() */
  22 #include <scsi/scsi_tcq.h>
  23 #include <scsi/iscsi_proto.h>
  24 #include <target/target_core_base.h>
  25 #include <target/target_core_fabric.h>
  26 #include <target/iscsi/iscsi_transport.h>
  27
  28 #include <target/iscsi/iscsi_target_core.h>
  29 #include "iscsi_target_parameters.h"
  30 #include "iscsi_target_seq_pdu_list.h"
  31 #include "iscsi_target_datain_values.h"
  32 #include "iscsi_target_erl0.h"
  33 #include "iscsi_target_erl1.h"
  34 #include "iscsi_target_erl2.h"
  35 #include "iscsi_target_tpg.h"
  36 #include "iscsi_target_util.h"
  37 #include "iscsi_target.h"
  38
  39 #define PRINT_BUFF(buff, len)                                   \
  40 {                                                               \
  41         int zzz;                                                \
  42                                                                 \
  43         pr_debug("%d:\n", __LINE__);                            \
  44         for (zzz = 0; zzz < len; zzz++) {                       \
  45                 if (zzz % 16 == 0) {                            \
  46                         if (zzz)                                \
  47                                 pr_debug("\n");                 \
  48                         pr_debug("%4i: ", zzz);                 \
  49                 }                                               \
  50                 pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  51         }                                                       \
  52         if ((len + 1) % 16)                                     \
  53                 pr_debug("\n");                                 \
  54 }
  55
  56 extern struct list_head g_tiqn_list;
  57 extern spinlock_t tiqn_lock;
  58
  59 /*
  60  *      Called with cmd->r2t_lock held.
  61  */
  62 int iscsit_add_r2t_to_list(
  63         struct iscsi_cmd *cmd,
  64         u32 offset,
  65         u32 xfer_len,
  66         int recovery,
  67         u32 r2t_sn)
  68 {
  69         struct iscsi_r2t *r2t;
  70
  71         r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  72         if (!r2t) {
  73                 pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  74                 return -1;
  75         }
  76         INIT_LIST_HEAD(&r2t->r2t_list);
  77
  78         r2t->recovery_r2t = recovery;
  79         r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  80         r2t->offset = offset;
  81         r2t->xfer_len = xfer_len;
  82         list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  83         spin_unlock_bh(&cmd->r2t_lock);
  84
  85         iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  86
  87         spin_lock_bh(&cmd->r2t_lock);
  88         return 0;
  89 }
  90
  91 struct iscsi_r2t *iscsit_get_r2t_for_eos(
  92         struct iscsi_cmd *cmd,
  93         u32 offset,
  94         u32 length)
  95 {
  96         struct iscsi_r2t *r2t;
  97
  98         spin_lock_bh(&cmd->r2t_lock);
  99         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 100                 if ((r2t->offset <= offset) &&
 101                     (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 102                         spin_unlock_bh(&cmd->r2t_lock);
 103                         return r2t;
 104                 }
 105         }
 106         spin_unlock_bh(&cmd->r2t_lock);
 107
 108         pr_err("Unable to locate R2T for Offset: %u, Length:"
 109                         " %u\n", offset, length);
 110         return NULL;
 111 }
 112
 113 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 114 {
 115         struct iscsi_r2t *r2t;
 116
 117         spin_lock_bh(&cmd->r2t_lock);
 118         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 119                 if (!r2t->sent_r2t) {
 120                         spin_unlock_bh(&cmd->r2t_lock);
 121                         return r2t;
 122                 }
 123         }
 124         spin_unlock_bh(&cmd->r2t_lock);
 125
 126         pr_err("Unable to locate next R2T to send for ITT:"
 127                         " 0x%08x.\n", cmd->init_task_tag);
 128         return NULL;
 129 }
 130
 131 /*
 132  *      Called with cmd->r2t_lock held.
 133  */
 134 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 135 {
 136         list_del(&r2t->r2t_list);
 137         kmem_cache_free(lio_r2t_cache, r2t);
 138 }
 139
 140 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 141 {
 142         struct iscsi_r2t *r2t, *r2t_tmp;
 143
 144         spin_lock_bh(&cmd->r2t_lock);
 145         list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 146                 iscsit_free_r2t(r2t, cmd);
 147         spin_unlock_bh(&cmd->r2t_lock);
 148 }
 149
 150 /*
 151  * May be called from software interrupt (timer) context for allocating
 152  * iSCSI NopINs.
 153  */
 154 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, int state)
 155 {
 156         struct iscsi_cmd *cmd;
 157         struct se_session *se_sess = conn->sess->se_sess;
 158         int size, tag;
 159
 160         tag = percpu_ida_alloc(&se_sess->sess_tag_pool, state);
 161         if (tag < 0)
 162                 return NULL;
 163
 164         size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
 165         cmd = (struct iscsi_cmd *)(se_sess->sess_cmd_map + (tag * size));
 166         memset(cmd, 0, size);
 167
 168         cmd->se_cmd.map_tag = tag;
 169         cmd->conn = conn;
 170         INIT_LIST_HEAD(&cmd->i_conn_node);
 171         INIT_LIST_HEAD(&cmd->datain_list);
 172         INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 173         spin_lock_init(&cmd->datain_lock);
 174         spin_lock_init(&cmd->dataout_timeout_lock);
 175         spin_lock_init(&cmd->istate_lock);
 176         spin_lock_init(&cmd->error_lock);
 177         spin_lock_init(&cmd->r2t_lock);
 178
 179         return cmd;
 180 }
 181 EXPORT_SYMBOL(iscsit_allocate_cmd);
 182
 183 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 184         struct iscsi_cmd *cmd,
 185         u32 seq_send_order)
 186 {
 187         u32 i;
 188
 189         for (i = 0; i < cmd->seq_count; i++)
 190                 if (cmd->seq_list[i].seq_send_order == seq_send_order)
 191                         return &cmd->seq_list[i];
 192
 193         return NULL;
 194 }
 195
 196 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 197 {
 198         u32 i;
 199
 200         if (!cmd->seq_list) {
 201                 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 202                 return NULL;
 203         }
 204
 205         for (i = 0; i < cmd->seq_count; i++) {
 206                 if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 207                         continue;
 208                 if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 209                         cmd->seq_send_order++;
 210                         return &cmd->seq_list[i];
 211                 }
 212         }
 213
 214         return NULL;
 215 }
 216
 217 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 218         struct iscsi_cmd *cmd,
 219         u32 r2t_sn)
 220 {
 221         struct iscsi_r2t *r2t;
 222
 223         spin_lock_bh(&cmd->r2t_lock);
 224         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 225                 if (r2t->r2t_sn == r2t_sn) {
 226                         spin_unlock_bh(&cmd->r2t_lock);
 227                         return r2t;
 228                 }
 229         }
 230         spin_unlock_bh(&cmd->r2t_lock);
 231
 232         return NULL;
 233 }
 234
 235 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 236 {
 237         u32 max_cmdsn;
 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         max_cmdsn = atomic_read(&sess->max_cmd_sn);
 247         if (iscsi_sna_gt(cmdsn, max_cmdsn)) {
 248                 pr_err("Received CmdSN: 0x%08x is greater than"
 249                        " MaxCmdSN: 0x%08x, ignoring.\n", cmdsn, max_cmdsn);
 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 EXPORT_SYMBOL(iscsit_find_cmd_from_itt);
 394
 395 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 396         struct iscsi_conn *conn,
 397         itt_t init_task_tag,
 398         u32 length)
 399 {
 400         struct iscsi_cmd *cmd;
 401
 402         spin_lock_bh(&conn->cmd_lock);
 403         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 404                 if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT)
 405                         continue;
 406                 if (cmd->init_task_tag == init_task_tag) {
 407                         spin_unlock_bh(&conn->cmd_lock);
 408                         return cmd;
 409                 }
 410         }
 411         spin_unlock_bh(&conn->cmd_lock);
 412
 413         pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 414                         " dumping payload\n", init_task_tag, conn->cid);
 415         if (length)
 416                 iscsit_dump_data_payload(conn, length, 1);
 417
 418         return NULL;
 419 }
 420
 421 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 422         struct iscsi_conn *conn,
 423         u32 targ_xfer_tag)
 424 {
 425         struct iscsi_cmd *cmd = NULL;
 426
 427         spin_lock_bh(&conn->cmd_lock);
 428         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 429                 if (cmd->targ_xfer_tag == targ_xfer_tag) {
 430                         spin_unlock_bh(&conn->cmd_lock);
 431                         return cmd;
 432                 }
 433         }
 434         spin_unlock_bh(&conn->cmd_lock);
 435
 436         pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 437                         targ_xfer_tag, conn->cid);
 438         return NULL;
 439 }
 440
 441 int iscsit_find_cmd_for_recovery(
 442         struct iscsi_session *sess,
 443         struct iscsi_cmd **cmd_ptr,
 444         struct iscsi_conn_recovery **cr_ptr,
 445         itt_t init_task_tag)
 446 {
 447         struct iscsi_cmd *cmd = NULL;
 448         struct iscsi_conn_recovery *cr;
 449         /*
 450          * Scan through the inactive connection recovery list's command list.
 451          * If init_task_tag matches the command is still alligent.
 452          */
 453         spin_lock(&sess->cr_i_lock);
 454         list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 455                 spin_lock(&cr->conn_recovery_cmd_lock);
 456                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 457                         if (cmd->init_task_tag == init_task_tag) {
 458                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 459                                 spin_unlock(&sess->cr_i_lock);
 460
 461                                 *cr_ptr = cr;
 462                                 *cmd_ptr = cmd;
 463                                 return -2;
 464                         }
 465                 }
 466                 spin_unlock(&cr->conn_recovery_cmd_lock);
 467         }
 468         spin_unlock(&sess->cr_i_lock);
 469         /*
 470          * Scan through the active connection recovery list's command list.
 471          * If init_task_tag matches the command is ready to be reassigned.
 472          */
 473         spin_lock(&sess->cr_a_lock);
 474         list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 475                 spin_lock(&cr->conn_recovery_cmd_lock);
 476                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 477                         if (cmd->init_task_tag == init_task_tag) {
 478                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 479                                 spin_unlock(&sess->cr_a_lock);
 480
 481                                 *cr_ptr = cr;
 482                                 *cmd_ptr = cmd;
 483                                 return 0;
 484                         }
 485                 }
 486                 spin_unlock(&cr->conn_recovery_cmd_lock);
 487         }
 488         spin_unlock(&sess->cr_a_lock);
 489
 490         return -1;
 491 }
 492
 493 void iscsit_add_cmd_to_immediate_queue(
 494         struct iscsi_cmd *cmd,
 495         struct iscsi_conn *conn,
 496         u8 state)
 497 {
 498         struct iscsi_queue_req *qr;
 499
 500         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 501         if (!qr) {
 502                 pr_err("Unable to allocate memory for"
 503                                 " struct iscsi_queue_req\n");
 504                 return;
 505         }
 506         INIT_LIST_HEAD(&qr->qr_list);
 507         qr->cmd = cmd;
 508         qr->state = state;
 509
 510         spin_lock_bh(&conn->immed_queue_lock);
 511         list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 512         atomic_inc(&cmd->immed_queue_count);
 513         atomic_set(&conn->check_immediate_queue, 1);
 514         spin_unlock_bh(&conn->immed_queue_lock);
 515
 516         wake_up(&conn->queues_wq);
 517 }
 518 EXPORT_SYMBOL(iscsit_add_cmd_to_immediate_queue);
 519
 520 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 521 {
 522         struct iscsi_queue_req *qr;
 523
 524         spin_lock_bh(&conn->immed_queue_lock);
 525         if (list_empty(&conn->immed_queue_list)) {
 526                 spin_unlock_bh(&conn->immed_queue_lock);
 527                 return NULL;
 528         }
 529         qr = list_first_entry(&conn->immed_queue_list,
 530                               struct iscsi_queue_req, qr_list);
 531
 532         list_del(&qr->qr_list);
 533         if (qr->cmd)
 534                 atomic_dec(&qr->cmd->immed_queue_count);
 535         spin_unlock_bh(&conn->immed_queue_lock);
 536
 537         return qr;
 538 }
 539
 540 static void iscsit_remove_cmd_from_immediate_queue(
 541         struct iscsi_cmd *cmd,
 542         struct iscsi_conn *conn)
 543 {
 544         struct iscsi_queue_req *qr, *qr_tmp;
 545
 546         spin_lock_bh(&conn->immed_queue_lock);
 547         if (!atomic_read(&cmd->immed_queue_count)) {
 548                 spin_unlock_bh(&conn->immed_queue_lock);
 549                 return;
 550         }
 551
 552         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 553                 if (qr->cmd != cmd)
 554                         continue;
 555
 556                 atomic_dec(&qr->cmd->immed_queue_count);
 557                 list_del(&qr->qr_list);
 558                 kmem_cache_free(lio_qr_cache, qr);
 559         }
 560         spin_unlock_bh(&conn->immed_queue_lock);
 561
 562         if (atomic_read(&cmd->immed_queue_count)) {
 563                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 564                         cmd->init_task_tag,
 565                         atomic_read(&cmd->immed_queue_count));
 566         }
 567 }
 568
 569 void iscsit_add_cmd_to_response_queue(
 570         struct iscsi_cmd *cmd,
 571         struct iscsi_conn *conn,
 572         u8 state)
 573 {
 574         struct iscsi_queue_req *qr;
 575
 576         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 577         if (!qr) {
 578                 pr_err("Unable to allocate memory for"
 579                         " struct iscsi_queue_req\n");
 580                 return;
 581         }
 582         INIT_LIST_HEAD(&qr->qr_list);
 583         qr->cmd = cmd;
 584         qr->state = state;
 585
 586         spin_lock_bh(&conn->response_queue_lock);
 587         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 588         atomic_inc(&cmd->response_queue_count);
 589         spin_unlock_bh(&conn->response_queue_lock);
 590
 591         wake_up(&conn->queues_wq);
 592 }
 593
 594 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 595 {
 596         struct iscsi_queue_req *qr;
 597
 598         spin_lock_bh(&conn->response_queue_lock);
 599         if (list_empty(&conn->response_queue_list)) {
 600                 spin_unlock_bh(&conn->response_queue_lock);
 601                 return NULL;
 602         }
 603
 604         qr = list_first_entry(&conn->response_queue_list,
 605                               struct iscsi_queue_req, qr_list);
 606
 607         list_del(&qr->qr_list);
 608         if (qr->cmd)
 609                 atomic_dec(&qr->cmd->response_queue_count);
 610         spin_unlock_bh(&conn->response_queue_lock);
 611
 612         return qr;
 613 }
 614
 615 static void iscsit_remove_cmd_from_response_queue(
 616         struct iscsi_cmd *cmd,
 617         struct iscsi_conn *conn)
 618 {
 619         struct iscsi_queue_req *qr, *qr_tmp;
 620
 621         spin_lock_bh(&conn->response_queue_lock);
 622         if (!atomic_read(&cmd->response_queue_count)) {
 623                 spin_unlock_bh(&conn->response_queue_lock);
 624                 return;
 625         }
 626
 627         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 628                                 qr_list) {
 629                 if (qr->cmd != cmd)
 630                         continue;
 631
 632                 atomic_dec(&qr->cmd->response_queue_count);
 633                 list_del(&qr->qr_list);
 634                 kmem_cache_free(lio_qr_cache, qr);
 635         }
 636         spin_unlock_bh(&conn->response_queue_lock);
 637
 638         if (atomic_read(&cmd->response_queue_count)) {
 639                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 640                         cmd->init_task_tag,
 641                         atomic_read(&cmd->response_queue_count));
 642         }
 643 }
 644
 645 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 646 {
 647         bool empty;
 648
 649         spin_lock_bh(&conn->immed_queue_lock);
 650         empty = list_empty(&conn->immed_queue_list);
 651         spin_unlock_bh(&conn->immed_queue_lock);
 652
 653         if (!empty)
 654                 return empty;
 655
 656         spin_lock_bh(&conn->response_queue_lock);
 657         empty = list_empty(&conn->response_queue_list);
 658         spin_unlock_bh(&conn->response_queue_lock);
 659
 660         return empty;
 661 }
 662
 663 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 664 {
 665         struct iscsi_queue_req *qr, *qr_tmp;
 666
 667         spin_lock_bh(&conn->immed_queue_lock);
 668         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 669                 list_del(&qr->qr_list);
 670                 if (qr->cmd)
 671                         atomic_dec(&qr->cmd->immed_queue_count);
 672
 673                 kmem_cache_free(lio_qr_cache, qr);
 674         }
 675         spin_unlock_bh(&conn->immed_queue_lock);
 676
 677         spin_lock_bh(&conn->response_queue_lock);
 678         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 679                         qr_list) {
 680                 list_del(&qr->qr_list);
 681                 if (qr->cmd)
 682                         atomic_dec(&qr->cmd->response_queue_count);
 683
 684                 kmem_cache_free(lio_qr_cache, qr);
 685         }
 686         spin_unlock_bh(&conn->response_queue_lock);
 687 }
 688
 689 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 690 {
 691         struct iscsi_session *sess;
 692         struct se_cmd *se_cmd = &cmd->se_cmd;
 693
 694         if (cmd->conn)
 695                 sess = cmd->conn->sess;
 696         else
 697                 sess = cmd->sess;
 698
 699         BUG_ON(!sess || !sess->se_sess);
 700
 701         kfree(cmd->buf_ptr);
 702         kfree(cmd->pdu_list);
 703         kfree(cmd->seq_list);
 704         kfree(cmd->tmr_req);
 705         kfree(cmd->iov_data);
 706         kfree(cmd->text_in_ptr);
 707
 708         percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 709 }
 710 EXPORT_SYMBOL(iscsit_release_cmd);
 711
 712 void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool scsi_cmd,
 713                        bool check_queues)
 714 {
 715         struct iscsi_conn *conn = cmd->conn;
 716
 717         if (scsi_cmd) {
 718                 if (cmd->data_direction == DMA_TO_DEVICE) {
 719                         iscsit_stop_dataout_timer(cmd);
 720                         iscsit_free_r2ts_from_list(cmd);
 721                 }
 722                 if (cmd->data_direction == DMA_FROM_DEVICE)
 723                         iscsit_free_all_datain_reqs(cmd);
 724         }
 725
 726         if (conn && check_queues) {
 727                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 728                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 729         }
 730
 731         if (conn && conn->conn_transport->iscsit_release_cmd)
 732                 conn->conn_transport->iscsit_release_cmd(conn, cmd);
 733 }
 734
 735 void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 736 {
 737         struct se_cmd *se_cmd = NULL;
 738         int rc;
 739         /*
 740          * Determine if a struct se_cmd is associated with
 741          * this struct iscsi_cmd.
 742          */
 743         switch (cmd->iscsi_opcode) {
 744         case ISCSI_OP_SCSI_CMD:
 745                 se_cmd = &cmd->se_cmd;
 746                 __iscsit_free_cmd(cmd, true, shutdown);
 747                 /*
 748                  * Fallthrough
 749                  */
 750         case ISCSI_OP_SCSI_TMFUNC:
 751                 rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 752                 if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
 753                         __iscsit_free_cmd(cmd, true, shutdown);
 754                         target_put_sess_cmd(se_cmd);
 755                 }
 756                 break;
 757         case ISCSI_OP_REJECT:
 758                 /*
 759                  * Handle special case for REJECT when iscsi_add_reject*() has
 760                  * overwritten the original iscsi_opcode assignment, and the
 761                  * associated cmd->se_cmd needs to be released.
 762                  */
 763                 if (cmd->se_cmd.se_tfo != NULL) {
 764                         se_cmd = &cmd->se_cmd;
 765                         __iscsit_free_cmd(cmd, true, shutdown);
 766
 767                         rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 768                         if (!rc && shutdown && se_cmd->se_sess) {
 769                                 __iscsit_free_cmd(cmd, true, shutdown);
 770                                 target_put_sess_cmd(se_cmd);
 771                         }
 772                         break;
 773                 }
 774                 /* Fall-through */
 775         default:
 776                 __iscsit_free_cmd(cmd, false, shutdown);
 777                 iscsit_release_cmd(cmd);
 778                 break;
 779         }
 780 }
 781 EXPORT_SYMBOL(iscsit_free_cmd);
 782
 783 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 784 {
 785         spin_lock_bh(&sess->session_usage_lock);
 786         if (sess->session_usage_count != 0) {
 787                 sess->session_waiting_on_uc = 1;
 788                 spin_unlock_bh(&sess->session_usage_lock);
 789                 if (in_interrupt())
 790                         return 2;
 791
 792                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 793                 return 1;
 794         }
 795         spin_unlock_bh(&sess->session_usage_lock);
 796
 797         return 0;
 798 }
 799
 800 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 801 {
 802         spin_lock_bh(&sess->session_usage_lock);
 803         sess->session_usage_count--;
 804
 805         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 806                 complete(&sess->session_waiting_on_uc_comp);
 807
 808         spin_unlock_bh(&sess->session_usage_lock);
 809 }
 810
 811 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 812 {
 813         spin_lock_bh(&sess->session_usage_lock);
 814         sess->session_usage_count++;
 815         spin_unlock_bh(&sess->session_usage_lock);
 816 }
 817
 818 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 819 {
 820         struct iscsi_conn *conn;
 821
 822         spin_lock_bh(&sess->conn_lock);
 823         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 824                 if ((conn->cid == cid) &&
 825                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 826                         iscsit_inc_conn_usage_count(conn);
 827                         spin_unlock_bh(&sess->conn_lock);
 828                         return conn;
 829                 }
 830         }
 831         spin_unlock_bh(&sess->conn_lock);
 832
 833         return NULL;
 834 }
 835
 836 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 837 {
 838         struct iscsi_conn *conn;
 839
 840         spin_lock_bh(&sess->conn_lock);
 841         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 842                 if (conn->cid == cid) {
 843                         iscsit_inc_conn_usage_count(conn);
 844                         spin_lock(&conn->state_lock);
 845                         atomic_set(&conn->connection_wait_rcfr, 1);
 846                         spin_unlock(&conn->state_lock);
 847                         spin_unlock_bh(&sess->conn_lock);
 848                         return conn;
 849                 }
 850         }
 851         spin_unlock_bh(&sess->conn_lock);
 852
 853         return NULL;
 854 }
 855
 856 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 857 {
 858         spin_lock_bh(&conn->conn_usage_lock);
 859         if (conn->conn_usage_count != 0) {
 860                 conn->conn_waiting_on_uc = 1;
 861                 spin_unlock_bh(&conn->conn_usage_lock);
 862
 863                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 864                 return;
 865         }
 866         spin_unlock_bh(&conn->conn_usage_lock);
 867 }
 868
 869 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 870 {
 871         spin_lock_bh(&conn->conn_usage_lock);
 872         conn->conn_usage_count--;
 873
 874         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 875                 complete(&conn->conn_waiting_on_uc_comp);
 876
 877         spin_unlock_bh(&conn->conn_usage_lock);
 878 }
 879
 880 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 881 {
 882         spin_lock_bh(&conn->conn_usage_lock);
 883         conn->conn_usage_count++;
 884         spin_unlock_bh(&conn->conn_usage_lock);
 885 }
 886
 887 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 888 {
 889         u8 state;
 890         struct iscsi_cmd *cmd;
 891
 892         cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
 893         if (!cmd)
 894                 return -1;
 895
 896         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 897         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 898                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 899         cmd->init_task_tag = RESERVED_ITT;
 900         cmd->targ_xfer_tag = (want_response) ?
 901                              session_get_next_ttt(conn->sess) : 0xFFFFFFFF;
 902         spin_lock_bh(&conn->cmd_lock);
 903         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 904         spin_unlock_bh(&conn->cmd_lock);
 905
 906         if (want_response)
 907                 iscsit_start_nopin_response_timer(conn);
 908         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 909
 910         return 0;
 911 }
 912
 913 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 914 {
 915         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 916
 917         iscsit_inc_conn_usage_count(conn);
 918
 919         spin_lock_bh(&conn->nopin_timer_lock);
 920         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 921                 spin_unlock_bh(&conn->nopin_timer_lock);
 922                 iscsit_dec_conn_usage_count(conn);
 923                 return;
 924         }
 925
 926         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 927                 " SID: %u, failing connection.\n", conn->cid,
 928                         conn->sess->sid);
 929         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 930         spin_unlock_bh(&conn->nopin_timer_lock);
 931
 932         {
 933         struct iscsi_portal_group *tpg = conn->sess->tpg;
 934         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 935
 936         if (tiqn) {
 937                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 938                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 939                                 conn->sess->sess_ops->InitiatorName);
 940                 tiqn->sess_err_stats.last_sess_failure_type =
 941                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 942                 tiqn->sess_err_stats.cxn_timeout_errors++;
 943                 atomic_long_inc(&conn->sess->conn_timeout_errors);
 944                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 945         }
 946         }
 947
 948         iscsit_cause_connection_reinstatement(conn, 0);
 949         iscsit_dec_conn_usage_count(conn);
 950 }
 951
 952 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 953 {
 954         struct iscsi_session *sess = conn->sess;
 955         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 956
 957         spin_lock_bh(&conn->nopin_timer_lock);
 958         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 959                 spin_unlock_bh(&conn->nopin_timer_lock);
 960                 return;
 961         }
 962
 963         mod_timer(&conn->nopin_response_timer,
 964                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
 965         spin_unlock_bh(&conn->nopin_timer_lock);
 966 }
 967
 968 /*
 969  *      Called with conn->nopin_timer_lock held.
 970  */
 971 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
 972 {
 973         struct iscsi_session *sess = conn->sess;
 974         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 975
 976         spin_lock_bh(&conn->nopin_timer_lock);
 977         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
 978                 spin_unlock_bh(&conn->nopin_timer_lock);
 979                 return;
 980         }
 981
 982         init_timer(&conn->nopin_response_timer);
 983         conn->nopin_response_timer.expires =
 984                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
 985         conn->nopin_response_timer.data = (unsigned long)conn;
 986         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
 987         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
 988         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
 989         add_timer(&conn->nopin_response_timer);
 990
 991         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
 992                 " seconds\n", conn->cid, na->nopin_response_timeout);
 993         spin_unlock_bh(&conn->nopin_timer_lock);
 994 }
 995
 996 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
 997 {
 998         spin_lock_bh(&conn->nopin_timer_lock);
 999         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1000                 spin_unlock_bh(&conn->nopin_timer_lock);
1001                 return;
1002         }
1003         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1004         spin_unlock_bh(&conn->nopin_timer_lock);
1005
1006         del_timer_sync(&conn->nopin_response_timer);
1007
1008         spin_lock_bh(&conn->nopin_timer_lock);
1009         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1010         spin_unlock_bh(&conn->nopin_timer_lock);
1011 }
1012
1013 static void iscsit_handle_nopin_timeout(unsigned long data)
1014 {
1015         struct iscsi_conn *conn = (struct iscsi_conn *) data;
1016
1017         iscsit_inc_conn_usage_count(conn);
1018
1019         spin_lock_bh(&conn->nopin_timer_lock);
1020         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1021                 spin_unlock_bh(&conn->nopin_timer_lock);
1022                 iscsit_dec_conn_usage_count(conn);
1023                 return;
1024         }
1025         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1026         spin_unlock_bh(&conn->nopin_timer_lock);
1027
1028         iscsit_add_nopin(conn, 1);
1029         iscsit_dec_conn_usage_count(conn);
1030 }
1031
1032 /*
1033  * Called with conn->nopin_timer_lock held.
1034  */
1035 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1036 {
1037         struct iscsi_session *sess = conn->sess;
1038         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1039         /*
1040         * NOPIN timeout is disabled.
1041          */
1042         if (!na->nopin_timeout)
1043                 return;
1044
1045         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1046                 return;
1047
1048         init_timer(&conn->nopin_timer);
1049         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1050         conn->nopin_timer.data = (unsigned long)conn;
1051         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1052         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1053         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1054         add_timer(&conn->nopin_timer);
1055
1056         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1057                 " interval\n", conn->cid, na->nopin_timeout);
1058 }
1059
1060 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1061 {
1062         struct iscsi_session *sess = conn->sess;
1063         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1064         /*
1065          * NOPIN timeout is disabled..
1066          */
1067         if (!na->nopin_timeout)
1068                 return;
1069
1070         spin_lock_bh(&conn->nopin_timer_lock);
1071         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1072                 spin_unlock_bh(&conn->nopin_timer_lock);
1073                 return;
1074         }
1075
1076         init_timer(&conn->nopin_timer);
1077         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1078         conn->nopin_timer.data = (unsigned long)conn;
1079         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1080         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1081         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1082         add_timer(&conn->nopin_timer);
1083
1084         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1085                         " interval\n", conn->cid, na->nopin_timeout);
1086         spin_unlock_bh(&conn->nopin_timer_lock);
1087 }
1088
1089 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1090 {
1091         spin_lock_bh(&conn->nopin_timer_lock);
1092         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1093                 spin_unlock_bh(&conn->nopin_timer_lock);
1094                 return;
1095         }
1096         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1097         spin_unlock_bh(&conn->nopin_timer_lock);
1098
1099         del_timer_sync(&conn->nopin_timer);
1100
1101         spin_lock_bh(&conn->nopin_timer_lock);
1102         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1103         spin_unlock_bh(&conn->nopin_timer_lock);
1104 }
1105
1106 int iscsit_send_tx_data(
1107         struct iscsi_cmd *cmd,
1108         struct iscsi_conn *conn,
1109         int use_misc)
1110 {
1111         int tx_sent, tx_size;
1112         u32 iov_count;
1113         struct kvec *iov;
1114
1115 send_data:
1116         tx_size = cmd->tx_size;
1117
1118         if (!use_misc) {
1119                 iov = &cmd->iov_data[0];
1120                 iov_count = cmd->iov_data_count;
1121         } else {
1122                 iov = &cmd->iov_misc[0];
1123                 iov_count = cmd->iov_misc_count;
1124         }
1125
1126         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1127         if (tx_size != tx_sent) {
1128                 if (tx_sent == -EAGAIN) {
1129                         pr_err("tx_data() returned -EAGAIN\n");
1130                         goto send_data;
1131                 } else
1132                         return -1;
1133         }
1134         cmd->tx_size = 0;
1135
1136         return 0;
1137 }
1138
1139 int iscsit_fe_sendpage_sg(
1140         struct iscsi_cmd *cmd,
1141         struct iscsi_conn *conn)
1142 {
1143         struct scatterlist *sg = cmd->first_data_sg;
1144         struct kvec iov;
1145         u32 tx_hdr_size, data_len;
1146         u32 offset = cmd->first_data_sg_off;
1147         int tx_sent, iov_off;
1148
1149 send_hdr:
1150         tx_hdr_size = ISCSI_HDR_LEN;
1151         if (conn->conn_ops->HeaderDigest)
1152                 tx_hdr_size += ISCSI_CRC_LEN;
1153
1154         iov.iov_base = cmd->pdu;
1155         iov.iov_len = tx_hdr_size;
1156
1157         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1158         if (tx_hdr_size != tx_sent) {
1159                 if (tx_sent == -EAGAIN) {
1160                         pr_err("tx_data() returned -EAGAIN\n");
1161                         goto send_hdr;
1162                 }
1163                 return -1;
1164         }
1165
1166         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1167         /*
1168          * Set iov_off used by padding and data digest tx_data() calls below
1169          * in order to determine proper offset into cmd->iov_data[]
1170          */
1171         if (conn->conn_ops->DataDigest) {
1172                 data_len -= ISCSI_CRC_LEN;
1173                 if (cmd->padding)
1174                         iov_off = (cmd->iov_data_count - 2);
1175                 else
1176                         iov_off = (cmd->iov_data_count - 1);
1177         } else {
1178                 iov_off = (cmd->iov_data_count - 1);
1179         }
1180         /*
1181          * Perform sendpage() for each page in the scatterlist
1182          */
1183         while (data_len) {
1184                 u32 space = (sg->length - offset);
1185                 u32 sub_len = min_t(u32, data_len, space);
1186 send_pg:
1187                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1188                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1189                 if (tx_sent != sub_len) {
1190                         if (tx_sent == -EAGAIN) {
1191                                 pr_err("tcp_sendpage() returned"
1192                                                 " -EAGAIN\n");
1193                                 goto send_pg;
1194                         }
1195
1196                         pr_err("tcp_sendpage() failure: %d\n",
1197                                         tx_sent);
1198                         return -1;
1199                 }
1200
1201                 data_len -= sub_len;
1202                 offset = 0;
1203                 sg = sg_next(sg);
1204         }
1205
1206 send_padding:
1207         if (cmd->padding) {
1208                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1209
1210                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1211                 if (cmd->padding != tx_sent) {
1212                         if (tx_sent == -EAGAIN) {
1213                                 pr_err("tx_data() returned -EAGAIN\n");
1214                                 goto send_padding;
1215                         }
1216                         return -1;
1217                 }
1218         }
1219
1220 send_datacrc:
1221         if (conn->conn_ops->DataDigest) {
1222                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1223
1224                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1225                 if (ISCSI_CRC_LEN != tx_sent) {
1226                         if (tx_sent == -EAGAIN) {
1227                                 pr_err("tx_data() returned -EAGAIN\n");
1228                                 goto send_datacrc;
1229                         }
1230                         return -1;
1231                 }
1232         }
1233
1234         return 0;
1235 }
1236
1237 /*
1238  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1239  *      back to the Initiator when an expection condition occurs with the
1240  *      errors set in status_class and status_detail.
1241  *
1242  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1243  *      Returns:        0 on success, -1 on error.
1244  */
1245 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1246 {
1247         struct iscsi_login_rsp *hdr;
1248         struct iscsi_login *login = conn->conn_login;
1249
1250         login->login_failed = 1;
1251         iscsit_collect_login_stats(conn, status_class, status_detail);
1252
1253         memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1254
1255         hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1256         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1257         hdr->status_class       = status_class;
1258         hdr->status_detail      = status_detail;
1259         hdr->itt                = conn->login_itt;
1260
1261         return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1262 }
1263
1264 void iscsit_print_session_params(struct iscsi_session *sess)
1265 {
1266         struct iscsi_conn *conn;
1267
1268         pr_debug("-----------------------------[Session Params for"
1269                 " SID: %u]-----------------------------\n", sess->sid);
1270         spin_lock_bh(&sess->conn_lock);
1271         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1272                 iscsi_dump_conn_ops(conn->conn_ops);
1273         spin_unlock_bh(&sess->conn_lock);
1274
1275         iscsi_dump_sess_ops(sess->sess_ops);
1276 }
1277
1278 static int iscsit_do_rx_data(
1279         struct iscsi_conn *conn,
1280         struct iscsi_data_count *count)
1281 {
1282         int data = count->data_length, rx_loop = 0, total_rx = 0;
1283         struct msghdr msg;
1284
1285         if (!conn || !conn->sock || !conn->conn_ops)
1286                 return -1;
1287
1288         memset(&msg, 0, sizeof(struct msghdr));
1289         iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC,
1290                       count->iov, count->iov_count, data);
1291
1292         while (msg_data_left(&msg)) {
1293                 rx_loop = sock_recvmsg(conn->sock, &msg, MSG_WAITALL);
1294                 if (rx_loop <= 0) {
1295                         pr_debug("rx_loop: %d total_rx: %d\n",
1296                                 rx_loop, total_rx);
1297                         return rx_loop;
1298                 }
1299                 total_rx += rx_loop;
1300                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1301                                 rx_loop, total_rx, data);
1302         }
1303
1304         return total_rx;
1305 }
1306
1307 static int iscsit_do_tx_data(
1308         struct iscsi_conn *conn,
1309         struct iscsi_data_count *count)
1310 {
1311         int ret, iov_len;
1312         struct kvec *iov_p;
1313         struct msghdr msg;
1314
1315         if (!conn || !conn->sock || !conn->conn_ops)
1316                 return -1;
1317
1318         if (count->data_length <= 0) {
1319                 pr_err("Data length is: %d\n", count->data_length);
1320                 return -1;
1321         }
1322
1323         memset(&msg, 0, sizeof(struct msghdr));
1324
1325         iov_p = count->iov;
1326         iov_len = count->iov_count;
1327
1328         ret = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1329                              count->data_length);
1330         if (ret != count->data_length) {
1331                 pr_err("Unexpected ret: %d send data %d\n",
1332                        ret, count->data_length);
1333                 return -EPIPE;
1334         }
1335         pr_debug("ret: %d, sent data: %d\n", ret, count->data_length);
1336
1337         return ret;
1338 }
1339
1340 int rx_data(
1341         struct iscsi_conn *conn,
1342         struct kvec *iov,
1343         int iov_count,
1344         int data)
1345 {
1346         struct iscsi_data_count c;
1347
1348         if (!conn || !conn->sock || !conn->conn_ops)
1349                 return -1;
1350
1351         memset(&c, 0, sizeof(struct iscsi_data_count));
1352         c.iov = iov;
1353         c.iov_count = iov_count;
1354         c.data_length = data;
1355         c.type = ISCSI_RX_DATA;
1356
1357         return iscsit_do_rx_data(conn, &c);
1358 }
1359
1360 int tx_data(
1361         struct iscsi_conn *conn,
1362         struct kvec *iov,
1363         int iov_count,
1364         int data)
1365 {
1366         struct iscsi_data_count c;
1367
1368         if (!conn || !conn->sock || !conn->conn_ops)
1369                 return -1;
1370
1371         memset(&c, 0, sizeof(struct iscsi_data_count));
1372         c.iov = iov;
1373         c.iov_count = iov_count;
1374         c.data_length = data;
1375         c.type = ISCSI_TX_DATA;
1376
1377         return iscsit_do_tx_data(conn, &c);
1378 }
1379
1380 static bool sockaddr_equal(struct sockaddr_storage *x, struct sockaddr_storage *y)
1381 {
1382         switch (x->ss_family) {
1383         case AF_INET: {
1384                 struct sockaddr_in *sinx = (struct sockaddr_in *)x;
1385                 struct sockaddr_in *siny = (struct sockaddr_in *)y;
1386                 if (sinx->sin_addr.s_addr != siny->sin_addr.s_addr)
1387                         return false;
1388                 if (sinx->sin_port != siny->sin_port)
1389                         return false;
1390                 break;
1391         }
1392         case AF_INET6: {
1393                 struct sockaddr_in6 *sinx = (struct sockaddr_in6 *)x;
1394                 struct sockaddr_in6 *siny = (struct sockaddr_in6 *)y;
1395                 if (!ipv6_addr_equal(&sinx->sin6_addr, &siny->sin6_addr))
1396                         return false;
1397                 if (sinx->sin6_port != siny->sin6_port)
1398                         return false;
1399                 break;
1400         }
1401         default:
1402                 return false;
1403         }
1404         return true;
1405 }
1406
1407 void iscsit_collect_login_stats(
1408         struct iscsi_conn *conn,
1409         u8 status_class,
1410         u8 status_detail)
1411 {
1412         struct iscsi_param *intrname = NULL;
1413         struct iscsi_tiqn *tiqn;
1414         struct iscsi_login_stats *ls;
1415
1416         tiqn = iscsit_snmp_get_tiqn(conn);
1417         if (!tiqn)
1418                 return;
1419
1420         ls = &tiqn->login_stats;
1421
1422         spin_lock(&ls->lock);
1423         if (sockaddr_equal(&conn->login_sockaddr, &ls->last_intr_fail_sockaddr) &&
1424             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1425                 /* We already have the failure info for this login */
1426                 spin_unlock(&ls->lock);
1427                 return;
1428         }
1429
1430         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1431                 ls->accepts++;
1432         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1433                 ls->redirects++;
1434                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1435         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1436                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1437                 ls->authenticate_fails++;
1438                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1439         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1440                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1441                 ls->authorize_fails++;
1442                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1443         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1444                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1445                 ls->negotiate_fails++;
1446                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1447         } else {
1448                 ls->other_fails++;
1449                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1450         }
1451
1452         /* Save initiator name, ip address and time, if it is a failed login */
1453         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1454                 if (conn->param_list)
1455                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1456                                                              conn->param_list);
1457                 strlcpy(ls->last_intr_fail_name,
1458                        (intrname ? intrname->value : "Unknown"),
1459                        sizeof(ls->last_intr_fail_name));
1460
1461                 ls->last_intr_fail_ip_family = conn->login_family;
1462
1463                 ls->last_intr_fail_sockaddr = conn->login_sockaddr;
1464                 ls->last_fail_time = get_jiffies_64();
1465         }
1466
1467         spin_unlock(&ls->lock);
1468 }
1469
1470 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1471 {
1472         struct iscsi_portal_group *tpg;
1473
1474         if (!conn || !conn->sess)
1475                 return NULL;
1476
1477         tpg = conn->sess->tpg;
1478         if (!tpg)
1479                 return NULL;
1480
1481         if (!tpg->tpg_tiqn)
1482                 return NULL;
1483
1484         return tpg->tpg_tiqn;
1485 }