Pileus Git - ~andy/linux/blob - drivers/target/iscsi/iscsi_target_util.c

   1 /*******************************************************************************
   2  * This file contains the iSCSI Target specific utility functions.
   3  *
   4  * \u00a9 Copyright 2007-2011 RisingTide Systems LLC.
   5  *
   6  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   7  *
   8  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  ******************************************************************************/
  20
  21 #include <linux/list.h>
  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/target_core_configfs.h>
  27 #include <target/iscsi/iscsi_transport.h>
  28
  29 #include "iscsi_target_core.h"
  30 #include "iscsi_target_parameters.h"
  31 #include "iscsi_target_seq_pdu_list.h"
  32 #include "iscsi_target_datain_values.h"
  33 #include "iscsi_target_erl0.h"
  34 #include "iscsi_target_erl1.h"
  35 #include "iscsi_target_erl2.h"
  36 #include "iscsi_target_tpg.h"
  37 #include "iscsi_target_tq.h"
  38 #include "iscsi_target_util.h"
  39 #include "iscsi_target.h"
  40
  41 #define PRINT_BUFF(buff, len)                                   \
  42 {                                                               \
  43         int zzz;                                                \
  44                                                                 \
  45         pr_debug("%d:\n", __LINE__);                            \
  46         for (zzz = 0; zzz < len; zzz++) {                       \
  47                 if (zzz % 16 == 0) {                            \
  48                         if (zzz)                                \
  49                                 pr_debug("\n");                 \
  50                         pr_debug("%4i: ", zzz);                 \
  51                 }                                               \
  52                 pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  53         }                                                       \
  54         if ((len + 1) % 16)                                     \
  55                 pr_debug("\n");                                 \
  56 }
  57
  58 extern struct list_head g_tiqn_list;
  59 extern spinlock_t tiqn_lock;
  60
  61 /*
  62  *      Called with cmd->r2t_lock held.
  63  */
  64 int iscsit_add_r2t_to_list(
  65         struct iscsi_cmd *cmd,
  66         u32 offset,
  67         u32 xfer_len,
  68         int recovery,
  69         u32 r2t_sn)
  70 {
  71         struct iscsi_r2t *r2t;
  72
  73         r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  74         if (!r2t) {
  75                 pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  76                 return -1;
  77         }
  78         INIT_LIST_HEAD(&r2t->r2t_list);
  79
  80         r2t->recovery_r2t = recovery;
  81         r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  82         r2t->offset = offset;
  83         r2t->xfer_len = xfer_len;
  84         list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  85         spin_unlock_bh(&cmd->r2t_lock);
  86
  87         iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  88
  89         spin_lock_bh(&cmd->r2t_lock);
  90         return 0;
  91 }
  92
  93 struct iscsi_r2t *iscsit_get_r2t_for_eos(
  94         struct iscsi_cmd *cmd,
  95         u32 offset,
  96         u32 length)
  97 {
  98         struct iscsi_r2t *r2t;
  99
 100         spin_lock_bh(&cmd->r2t_lock);
 101         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 102                 if ((r2t->offset <= offset) &&
 103                     (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 104                         spin_unlock_bh(&cmd->r2t_lock);
 105                         return r2t;
 106                 }
 107         }
 108         spin_unlock_bh(&cmd->r2t_lock);
 109
 110         pr_err("Unable to locate R2T for Offset: %u, Length:"
 111                         " %u\n", offset, length);
 112         return NULL;
 113 }
 114
 115 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 116 {
 117         struct iscsi_r2t *r2t;
 118
 119         spin_lock_bh(&cmd->r2t_lock);
 120         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 121                 if (!r2t->sent_r2t) {
 122                         spin_unlock_bh(&cmd->r2t_lock);
 123                         return r2t;
 124                 }
 125         }
 126         spin_unlock_bh(&cmd->r2t_lock);
 127
 128         pr_err("Unable to locate next R2T to send for ITT:"
 129                         " 0x%08x.\n", cmd->init_task_tag);
 130         return NULL;
 131 }
 132
 133 /*
 134  *      Called with cmd->r2t_lock held.
 135  */
 136 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 137 {
 138         list_del(&r2t->r2t_list);
 139         kmem_cache_free(lio_r2t_cache, r2t);
 140 }
 141
 142 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 143 {
 144         struct iscsi_r2t *r2t, *r2t_tmp;
 145
 146         spin_lock_bh(&cmd->r2t_lock);
 147         list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 148                 iscsit_free_r2t(r2t, cmd);
 149         spin_unlock_bh(&cmd->r2t_lock);
 150 }
 151
 152 struct iscsi_cmd *iscsit_alloc_cmd(struct iscsi_conn *conn, gfp_t gfp_mask)
 153 {
 154         struct iscsi_cmd *cmd;
 155
 156         cmd = kmem_cache_zalloc(lio_cmd_cache, gfp_mask);
 157         if (!cmd)
 158                 return NULL;
 159
 160         cmd->release_cmd = &iscsit_release_cmd;
 161         return cmd;
 162 }
 163
 164 /*
 165  * May be called from software interrupt (timer) context for allocating
 166  * iSCSI NopINs.
 167  */
 168 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, gfp_t gfp_mask)
 169 {
 170         struct iscsi_cmd *cmd;
 171
 172         cmd = conn->conn_transport->iscsit_alloc_cmd(conn, gfp_mask);
 173         if (!cmd) {
 174                 pr_err("Unable to allocate memory for struct iscsi_cmd.\n");
 175                 return NULL;
 176         }
 177         cmd->conn = conn;
 178         INIT_LIST_HEAD(&cmd->i_conn_node);
 179         INIT_LIST_HEAD(&cmd->datain_list);
 180         INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 181         init_completion(&cmd->reject_comp);
 182         spin_lock_init(&cmd->datain_lock);
 183         spin_lock_init(&cmd->dataout_timeout_lock);
 184         spin_lock_init(&cmd->istate_lock);
 185         spin_lock_init(&cmd->error_lock);
 186         spin_lock_init(&cmd->r2t_lock);
 187
 188         return cmd;
 189 }
 190 EXPORT_SYMBOL(iscsit_allocate_cmd);
 191
 192 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 193         struct iscsi_cmd *cmd,
 194         u32 seq_send_order)
 195 {
 196         u32 i;
 197
 198         for (i = 0; i < cmd->seq_count; i++)
 199                 if (cmd->seq_list[i].seq_send_order == seq_send_order)
 200                         return &cmd->seq_list[i];
 201
 202         return NULL;
 203 }
 204
 205 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 206 {
 207         u32 i;
 208
 209         if (!cmd->seq_list) {
 210                 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 211                 return NULL;
 212         }
 213
 214         for (i = 0; i < cmd->seq_count; i++) {
 215                 if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 216                         continue;
 217                 if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 218                         cmd->seq_send_order++;
 219                         return &cmd->seq_list[i];
 220                 }
 221         }
 222
 223         return NULL;
 224 }
 225
 226 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 227         struct iscsi_cmd *cmd,
 228         u32 r2t_sn)
 229 {
 230         struct iscsi_r2t *r2t;
 231
 232         spin_lock_bh(&cmd->r2t_lock);
 233         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 234                 if (r2t->r2t_sn == r2t_sn) {
 235                         spin_unlock_bh(&cmd->r2t_lock);
 236                         return r2t;
 237                 }
 238         }
 239         spin_unlock_bh(&cmd->r2t_lock);
 240
 241         return NULL;
 242 }
 243
 244 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 245 {
 246         int ret;
 247
 248         /*
 249          * This is the proper method of checking received CmdSN against
 250          * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 251          * or order CmdSNs due to multiple connection sessions and/or
 252          * CRC failures.
 253          */
 254         if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) {
 255                 pr_err("Received CmdSN: 0x%08x is greater than"
 256                        " MaxCmdSN: 0x%08x, protocol error.\n", cmdsn,
 257                        sess->max_cmd_sn);
 258                 ret = CMDSN_ERROR_CANNOT_RECOVER;
 259
 260         } else if (cmdsn == sess->exp_cmd_sn) {
 261                 sess->exp_cmd_sn++;
 262                 pr_debug("Received CmdSN matches ExpCmdSN,"
 263                       " incremented ExpCmdSN to: 0x%08x\n",
 264                       sess->exp_cmd_sn);
 265                 ret = CMDSN_NORMAL_OPERATION;
 266
 267         } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 268                 pr_debug("Received CmdSN: 0x%08x is greater"
 269                       " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 270                       cmdsn, sess->exp_cmd_sn);
 271                 ret = CMDSN_HIGHER_THAN_EXP;
 272
 273         } else {
 274                 pr_err("Received CmdSN: 0x%08x is less than"
 275                        " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 276                        sess->exp_cmd_sn);
 277                 ret = CMDSN_LOWER_THAN_EXP;
 278         }
 279
 280         return ret;
 281 }
 282
 283 /*
 284  * Commands may be received out of order if MC/S is in use.
 285  * Ensure they are executed in CmdSN order.
 286  */
 287 int iscsit_sequence_cmd(
 288         struct iscsi_conn *conn,
 289         struct iscsi_cmd *cmd,
 290         __be32 cmdsn)
 291 {
 292         int ret;
 293         int cmdsn_ret;
 294
 295         mutex_lock(&conn->sess->cmdsn_mutex);
 296
 297         cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
 298         switch (cmdsn_ret) {
 299         case CMDSN_NORMAL_OPERATION:
 300                 ret = iscsit_execute_cmd(cmd, 0);
 301                 if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 302                         iscsit_execute_ooo_cmdsns(conn->sess);
 303                 break;
 304         case CMDSN_HIGHER_THAN_EXP:
 305                 ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
 306                 break;
 307         case CMDSN_LOWER_THAN_EXP:
 308                 cmd->i_state = ISTATE_REMOVE;
 309                 iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 310                 ret = cmdsn_ret;
 311                 break;
 312         default:
 313                 ret = cmdsn_ret;
 314                 break;
 315         }
 316         mutex_unlock(&conn->sess->cmdsn_mutex);
 317
 318         return ret;
 319 }
 320 EXPORT_SYMBOL(iscsit_sequence_cmd);
 321
 322 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 323 {
 324         struct iscsi_conn *conn = cmd->conn;
 325         struct se_cmd *se_cmd = &cmd->se_cmd;
 326         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 327         u32 payload_length = ntoh24(hdr->dlength);
 328
 329         if (conn->sess->sess_ops->InitialR2T) {
 330                 pr_err("Received unexpected unsolicited data"
 331                         " while InitialR2T=Yes, protocol error.\n");
 332                 transport_send_check_condition_and_sense(se_cmd,
 333                                 TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 334                 return -1;
 335         }
 336
 337         if ((cmd->first_burst_len + payload_length) >
 338              conn->sess->sess_ops->FirstBurstLength) {
 339                 pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 340                         " for this Unsolicited DataOut Burst.\n",
 341                         (cmd->first_burst_len + payload_length),
 342                                 conn->sess->sess_ops->FirstBurstLength);
 343                 transport_send_check_condition_and_sense(se_cmd,
 344                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 345                 return -1;
 346         }
 347
 348         if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 349                 return 0;
 350
 351         if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 352             ((cmd->first_burst_len + payload_length) !=
 353               conn->sess->sess_ops->FirstBurstLength)) {
 354                 pr_err("Unsolicited non-immediate data received %u"
 355                         " does not equal FirstBurstLength: %u, and does"
 356                         " not equal ExpXferLen %u.\n",
 357                         (cmd->first_burst_len + payload_length),
 358                         conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 359                 transport_send_check_condition_and_sense(se_cmd,
 360                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 361                 return -1;
 362         }
 363         return 0;
 364 }
 365
 366 struct iscsi_cmd *iscsit_find_cmd_from_itt(
 367         struct iscsi_conn *conn,
 368         itt_t init_task_tag)
 369 {
 370         struct iscsi_cmd *cmd;
 371
 372         spin_lock_bh(&conn->cmd_lock);
 373         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 374                 if (cmd->init_task_tag == init_task_tag) {
 375                         spin_unlock_bh(&conn->cmd_lock);
 376                         return cmd;
 377                 }
 378         }
 379         spin_unlock_bh(&conn->cmd_lock);
 380
 381         pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 382                         init_task_tag, conn->cid);
 383         return NULL;
 384 }
 385
 386 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 387         struct iscsi_conn *conn,
 388         itt_t init_task_tag,
 389         u32 length)
 390 {
 391         struct iscsi_cmd *cmd;
 392
 393         spin_lock_bh(&conn->cmd_lock);
 394         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 395                 if (cmd->init_task_tag == init_task_tag) {
 396                         spin_unlock_bh(&conn->cmd_lock);
 397                         return cmd;
 398                 }
 399         }
 400         spin_unlock_bh(&conn->cmd_lock);
 401
 402         pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 403                         " dumping payload\n", init_task_tag, conn->cid);
 404         if (length)
 405                 iscsit_dump_data_payload(conn, length, 1);
 406
 407         return NULL;
 408 }
 409
 410 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 411         struct iscsi_conn *conn,
 412         u32 targ_xfer_tag)
 413 {
 414         struct iscsi_cmd *cmd = NULL;
 415
 416         spin_lock_bh(&conn->cmd_lock);
 417         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 418                 if (cmd->targ_xfer_tag == targ_xfer_tag) {
 419                         spin_unlock_bh(&conn->cmd_lock);
 420                         return cmd;
 421                 }
 422         }
 423         spin_unlock_bh(&conn->cmd_lock);
 424
 425         pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 426                         targ_xfer_tag, conn->cid);
 427         return NULL;
 428 }
 429
 430 int iscsit_find_cmd_for_recovery(
 431         struct iscsi_session *sess,
 432         struct iscsi_cmd **cmd_ptr,
 433         struct iscsi_conn_recovery **cr_ptr,
 434         itt_t init_task_tag)
 435 {
 436         struct iscsi_cmd *cmd = NULL;
 437         struct iscsi_conn_recovery *cr;
 438         /*
 439          * Scan through the inactive connection recovery list's command list.
 440          * If init_task_tag matches the command is still alligent.
 441          */
 442         spin_lock(&sess->cr_i_lock);
 443         list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 444                 spin_lock(&cr->conn_recovery_cmd_lock);
 445                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 446                         if (cmd->init_task_tag == init_task_tag) {
 447                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 448                                 spin_unlock(&sess->cr_i_lock);
 449
 450                                 *cr_ptr = cr;
 451                                 *cmd_ptr = cmd;
 452                                 return -2;
 453                         }
 454                 }
 455                 spin_unlock(&cr->conn_recovery_cmd_lock);
 456         }
 457         spin_unlock(&sess->cr_i_lock);
 458         /*
 459          * Scan through the active connection recovery list's command list.
 460          * If init_task_tag matches the command is ready to be reassigned.
 461          */
 462         spin_lock(&sess->cr_a_lock);
 463         list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 464                 spin_lock(&cr->conn_recovery_cmd_lock);
 465                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 466                         if (cmd->init_task_tag == init_task_tag) {
 467                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 468                                 spin_unlock(&sess->cr_a_lock);
 469
 470                                 *cr_ptr = cr;
 471                                 *cmd_ptr = cmd;
 472                                 return 0;
 473                         }
 474                 }
 475                 spin_unlock(&cr->conn_recovery_cmd_lock);
 476         }
 477         spin_unlock(&sess->cr_a_lock);
 478
 479         return -1;
 480 }
 481
 482 void iscsit_add_cmd_to_immediate_queue(
 483         struct iscsi_cmd *cmd,
 484         struct iscsi_conn *conn,
 485         u8 state)
 486 {
 487         struct iscsi_queue_req *qr;
 488
 489         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 490         if (!qr) {
 491                 pr_err("Unable to allocate memory for"
 492                                 " struct iscsi_queue_req\n");
 493                 return;
 494         }
 495         INIT_LIST_HEAD(&qr->qr_list);
 496         qr->cmd = cmd;
 497         qr->state = state;
 498
 499         spin_lock_bh(&conn->immed_queue_lock);
 500         list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 501         atomic_inc(&cmd->immed_queue_count);
 502         atomic_set(&conn->check_immediate_queue, 1);
 503         spin_unlock_bh(&conn->immed_queue_lock);
 504
 505         wake_up(&conn->queues_wq);
 506 }
 507
 508 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 509 {
 510         struct iscsi_queue_req *qr;
 511
 512         spin_lock_bh(&conn->immed_queue_lock);
 513         if (list_empty(&conn->immed_queue_list)) {
 514                 spin_unlock_bh(&conn->immed_queue_lock);
 515                 return NULL;
 516         }
 517         qr = list_first_entry(&conn->immed_queue_list,
 518                               struct iscsi_queue_req, qr_list);
 519
 520         list_del(&qr->qr_list);
 521         if (qr->cmd)
 522                 atomic_dec(&qr->cmd->immed_queue_count);
 523         spin_unlock_bh(&conn->immed_queue_lock);
 524
 525         return qr;
 526 }
 527
 528 static void iscsit_remove_cmd_from_immediate_queue(
 529         struct iscsi_cmd *cmd,
 530         struct iscsi_conn *conn)
 531 {
 532         struct iscsi_queue_req *qr, *qr_tmp;
 533
 534         spin_lock_bh(&conn->immed_queue_lock);
 535         if (!atomic_read(&cmd->immed_queue_count)) {
 536                 spin_unlock_bh(&conn->immed_queue_lock);
 537                 return;
 538         }
 539
 540         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 541                 if (qr->cmd != cmd)
 542                         continue;
 543
 544                 atomic_dec(&qr->cmd->immed_queue_count);
 545                 list_del(&qr->qr_list);
 546                 kmem_cache_free(lio_qr_cache, qr);
 547         }
 548         spin_unlock_bh(&conn->immed_queue_lock);
 549
 550         if (atomic_read(&cmd->immed_queue_count)) {
 551                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 552                         cmd->init_task_tag,
 553                         atomic_read(&cmd->immed_queue_count));
 554         }
 555 }
 556
 557 void iscsit_add_cmd_to_response_queue(
 558         struct iscsi_cmd *cmd,
 559         struct iscsi_conn *conn,
 560         u8 state)
 561 {
 562         struct iscsi_queue_req *qr;
 563
 564         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 565         if (!qr) {
 566                 pr_err("Unable to allocate memory for"
 567                         " struct iscsi_queue_req\n");
 568                 return;
 569         }
 570         INIT_LIST_HEAD(&qr->qr_list);
 571         qr->cmd = cmd;
 572         qr->state = state;
 573
 574         spin_lock_bh(&conn->response_queue_lock);
 575         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 576         atomic_inc(&cmd->response_queue_count);
 577         spin_unlock_bh(&conn->response_queue_lock);
 578
 579         wake_up(&conn->queues_wq);
 580 }
 581
 582 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 583 {
 584         struct iscsi_queue_req *qr;
 585
 586         spin_lock_bh(&conn->response_queue_lock);
 587         if (list_empty(&conn->response_queue_list)) {
 588                 spin_unlock_bh(&conn->response_queue_lock);
 589                 return NULL;
 590         }
 591
 592         qr = list_first_entry(&conn->response_queue_list,
 593                               struct iscsi_queue_req, qr_list);
 594
 595         list_del(&qr->qr_list);
 596         if (qr->cmd)
 597                 atomic_dec(&qr->cmd->response_queue_count);
 598         spin_unlock_bh(&conn->response_queue_lock);
 599
 600         return qr;
 601 }
 602
 603 static void iscsit_remove_cmd_from_response_queue(
 604         struct iscsi_cmd *cmd,
 605         struct iscsi_conn *conn)
 606 {
 607         struct iscsi_queue_req *qr, *qr_tmp;
 608
 609         spin_lock_bh(&conn->response_queue_lock);
 610         if (!atomic_read(&cmd->response_queue_count)) {
 611                 spin_unlock_bh(&conn->response_queue_lock);
 612                 return;
 613         }
 614
 615         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 616                                 qr_list) {
 617                 if (qr->cmd != cmd)
 618                         continue;
 619
 620                 atomic_dec(&qr->cmd->response_queue_count);
 621                 list_del(&qr->qr_list);
 622                 kmem_cache_free(lio_qr_cache, qr);
 623         }
 624         spin_unlock_bh(&conn->response_queue_lock);
 625
 626         if (atomic_read(&cmd->response_queue_count)) {
 627                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 628                         cmd->init_task_tag,
 629                         atomic_read(&cmd->response_queue_count));
 630         }
 631 }
 632
 633 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 634 {
 635         bool empty;
 636
 637         spin_lock_bh(&conn->immed_queue_lock);
 638         empty = list_empty(&conn->immed_queue_list);
 639         spin_unlock_bh(&conn->immed_queue_lock);
 640
 641         if (!empty)
 642                 return empty;
 643
 644         spin_lock_bh(&conn->response_queue_lock);
 645         empty = list_empty(&conn->response_queue_list);
 646         spin_unlock_bh(&conn->response_queue_lock);
 647
 648         return empty;
 649 }
 650
 651 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 652 {
 653         struct iscsi_queue_req *qr, *qr_tmp;
 654
 655         spin_lock_bh(&conn->immed_queue_lock);
 656         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 657                 list_del(&qr->qr_list);
 658                 if (qr->cmd)
 659                         atomic_dec(&qr->cmd->immed_queue_count);
 660
 661                 kmem_cache_free(lio_qr_cache, qr);
 662         }
 663         spin_unlock_bh(&conn->immed_queue_lock);
 664
 665         spin_lock_bh(&conn->response_queue_lock);
 666         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 667                         qr_list) {
 668                 list_del(&qr->qr_list);
 669                 if (qr->cmd)
 670                         atomic_dec(&qr->cmd->response_queue_count);
 671
 672                 kmem_cache_free(lio_qr_cache, qr);
 673         }
 674         spin_unlock_bh(&conn->response_queue_lock);
 675 }
 676
 677 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 678 {
 679         struct iscsi_conn *conn = cmd->conn;
 680
 681         iscsit_free_r2ts_from_list(cmd);
 682         iscsit_free_all_datain_reqs(cmd);
 683
 684         kfree(cmd->buf_ptr);
 685         kfree(cmd->pdu_list);
 686         kfree(cmd->seq_list);
 687         kfree(cmd->tmr_req);
 688         kfree(cmd->iov_data);
 689
 690         if (conn) {
 691                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 692                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 693         }
 694
 695         kmem_cache_free(lio_cmd_cache, cmd);
 696 }
 697
 698 void iscsit_free_cmd(struct iscsi_cmd *cmd)
 699 {
 700         /*
 701          * Determine if a struct se_cmd is associated with
 702          * this struct iscsi_cmd.
 703          */
 704         switch (cmd->iscsi_opcode) {
 705         case ISCSI_OP_SCSI_CMD:
 706                 if (cmd->data_direction == DMA_TO_DEVICE)
 707                         iscsit_stop_dataout_timer(cmd);
 708                 /*
 709                  * Fallthrough
 710                  */
 711         case ISCSI_OP_SCSI_TMFUNC:
 712                 transport_generic_free_cmd(&cmd->se_cmd, 1);
 713                 break;
 714         case ISCSI_OP_REJECT:
 715                 /*
 716                  * Handle special case for REJECT when iscsi_add_reject*() has
 717                  * overwritten the original iscsi_opcode assignment, and the
 718                  * associated cmd->se_cmd needs to be released.
 719                  */
 720                 if (cmd->se_cmd.se_tfo != NULL) {
 721                         transport_generic_free_cmd(&cmd->se_cmd, 1);
 722                         break;
 723                 }
 724                 /* Fall-through */
 725         default:
 726                 cmd->release_cmd(cmd);
 727                 break;
 728         }
 729 }
 730
 731 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 732 {
 733         spin_lock_bh(&sess->session_usage_lock);
 734         if (sess->session_usage_count != 0) {
 735                 sess->session_waiting_on_uc = 1;
 736                 spin_unlock_bh(&sess->session_usage_lock);
 737                 if (in_interrupt())
 738                         return 2;
 739
 740                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 741                 return 1;
 742         }
 743         spin_unlock_bh(&sess->session_usage_lock);
 744
 745         return 0;
 746 }
 747
 748 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 749 {
 750         spin_lock_bh(&sess->session_usage_lock);
 751         sess->session_usage_count--;
 752
 753         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 754                 complete(&sess->session_waiting_on_uc_comp);
 755
 756         spin_unlock_bh(&sess->session_usage_lock);
 757 }
 758
 759 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 760 {
 761         spin_lock_bh(&sess->session_usage_lock);
 762         sess->session_usage_count++;
 763         spin_unlock_bh(&sess->session_usage_lock);
 764 }
 765
 766 /*
 767  *      Setup conn->if_marker and conn->of_marker values based upon
 768  *      the initial marker-less interval. (see iSCSI v19 A.2)
 769  */
 770 int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 771 {
 772         int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 773         /*
 774          * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 775          */
 776         u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 777         u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 778
 779         if (conn->conn_ops->OFMarker) {
 780                 /*
 781                  * Account for the first Login Command received not
 782                  * via iscsi_recv_msg().
 783                  */
 784                 conn->of_marker += ISCSI_HDR_LEN;
 785                 if (conn->of_marker <= OFMarkInt) {
 786                         conn->of_marker = (OFMarkInt - conn->of_marker);
 787                 } else {
 788                         login_ofmarker_count = (conn->of_marker / OFMarkInt);
 789                         next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 790                                         (login_ofmarker_count * MARKER_SIZE);
 791                         conn->of_marker = (next_marker - conn->of_marker);
 792                 }
 793                 conn->of_marker_offset = 0;
 794                 pr_debug("Setting OFMarker value to %u based on Initial"
 795                         " Markerless Interval.\n", conn->of_marker);
 796         }
 797
 798         if (conn->conn_ops->IFMarker) {
 799                 if (conn->if_marker <= IFMarkInt) {
 800                         conn->if_marker = (IFMarkInt - conn->if_marker);
 801                 } else {
 802                         login_ifmarker_count = (conn->if_marker / IFMarkInt);
 803                         next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 804                                         (login_ifmarker_count * MARKER_SIZE);
 805                         conn->if_marker = (next_marker - conn->if_marker);
 806                 }
 807                 pr_debug("Setting IFMarker value to %u based on Initial"
 808                         " Markerless Interval.\n", conn->if_marker);
 809         }
 810
 811         return 0;
 812 }
 813
 814 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 815 {
 816         struct iscsi_conn *conn;
 817
 818         spin_lock_bh(&sess->conn_lock);
 819         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 820                 if ((conn->cid == cid) &&
 821                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 822                         iscsit_inc_conn_usage_count(conn);
 823                         spin_unlock_bh(&sess->conn_lock);
 824                         return conn;
 825                 }
 826         }
 827         spin_unlock_bh(&sess->conn_lock);
 828
 829         return NULL;
 830 }
 831
 832 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 833 {
 834         struct iscsi_conn *conn;
 835
 836         spin_lock_bh(&sess->conn_lock);
 837         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 838                 if (conn->cid == cid) {
 839                         iscsit_inc_conn_usage_count(conn);
 840                         spin_lock(&conn->state_lock);
 841                         atomic_set(&conn->connection_wait_rcfr, 1);
 842                         spin_unlock(&conn->state_lock);
 843                         spin_unlock_bh(&sess->conn_lock);
 844                         return conn;
 845                 }
 846         }
 847         spin_unlock_bh(&sess->conn_lock);
 848
 849         return NULL;
 850 }
 851
 852 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 853 {
 854         spin_lock_bh(&conn->conn_usage_lock);
 855         if (conn->conn_usage_count != 0) {
 856                 conn->conn_waiting_on_uc = 1;
 857                 spin_unlock_bh(&conn->conn_usage_lock);
 858
 859                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 860                 return;
 861         }
 862         spin_unlock_bh(&conn->conn_usage_lock);
 863 }
 864
 865 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 866 {
 867         spin_lock_bh(&conn->conn_usage_lock);
 868         conn->conn_usage_count--;
 869
 870         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 871                 complete(&conn->conn_waiting_on_uc_comp);
 872
 873         spin_unlock_bh(&conn->conn_usage_lock);
 874 }
 875
 876 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 877 {
 878         spin_lock_bh(&conn->conn_usage_lock);
 879         conn->conn_usage_count++;
 880         spin_unlock_bh(&conn->conn_usage_lock);
 881 }
 882
 883 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 884 {
 885         u8 state;
 886         struct iscsi_cmd *cmd;
 887
 888         cmd = iscsit_allocate_cmd(conn, GFP_ATOMIC);
 889         if (!cmd)
 890                 return -1;
 891
 892         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 893         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 894                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 895         cmd->init_task_tag = RESERVED_ITT;
 896         spin_lock_bh(&conn->sess->ttt_lock);
 897         cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
 898                         0xFFFFFFFF;
 899         if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
 900                 cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
 901         spin_unlock_bh(&conn->sess->ttt_lock);
 902
 903         spin_lock_bh(&conn->cmd_lock);
 904         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 905         spin_unlock_bh(&conn->cmd_lock);
 906
 907         if (want_response)
 908                 iscsit_start_nopin_response_timer(conn);
 909         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 910
 911         return 0;
 912 }
 913
 914 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 915 {
 916         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 917
 918         iscsit_inc_conn_usage_count(conn);
 919
 920         spin_lock_bh(&conn->nopin_timer_lock);
 921         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 922                 spin_unlock_bh(&conn->nopin_timer_lock);
 923                 iscsit_dec_conn_usage_count(conn);
 924                 return;
 925         }
 926
 927         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 928                 " SID: %u, failing connection.\n", conn->cid,
 929                         conn->sess->sid);
 930         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 931         spin_unlock_bh(&conn->nopin_timer_lock);
 932
 933         {
 934         struct iscsi_portal_group *tpg = conn->sess->tpg;
 935         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 936
 937         if (tiqn) {
 938                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 939                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 940                                 conn->sess->sess_ops->InitiatorName);
 941                 tiqn->sess_err_stats.last_sess_failure_type =
 942                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 943                 tiqn->sess_err_stats.cxn_timeout_errors++;
 944                 conn->sess->conn_timeout_errors++;
 945                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 946         }
 947         }
 948
 949         iscsit_cause_connection_reinstatement(conn, 0);
 950         iscsit_dec_conn_usage_count(conn);
 951 }
 952
 953 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 954 {
 955         struct iscsi_session *sess = conn->sess;
 956         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 957
 958         spin_lock_bh(&conn->nopin_timer_lock);
 959         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 960                 spin_unlock_bh(&conn->nopin_timer_lock);
 961                 return;
 962         }
 963
 964         mod_timer(&conn->nopin_response_timer,
 965                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
 966         spin_unlock_bh(&conn->nopin_timer_lock);
 967 }
 968
 969 /*
 970  *      Called with conn->nopin_timer_lock held.
 971  */
 972 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
 973 {
 974         struct iscsi_session *sess = conn->sess;
 975         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 976
 977         spin_lock_bh(&conn->nopin_timer_lock);
 978         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
 979                 spin_unlock_bh(&conn->nopin_timer_lock);
 980                 return;
 981         }
 982
 983         init_timer(&conn->nopin_response_timer);
 984         conn->nopin_response_timer.expires =
 985                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
 986         conn->nopin_response_timer.data = (unsigned long)conn;
 987         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
 988         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
 989         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
 990         add_timer(&conn->nopin_response_timer);
 991
 992         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
 993                 " seconds\n", conn->cid, na->nopin_response_timeout);
 994         spin_unlock_bh(&conn->nopin_timer_lock);
 995 }
 996
 997 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
 998 {
 999         spin_lock_bh(&conn->nopin_timer_lock);
1000         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1001                 spin_unlock_bh(&conn->nopin_timer_lock);
1002                 return;
1003         }
1004         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1005         spin_unlock_bh(&conn->nopin_timer_lock);
1006
1007         del_timer_sync(&conn->nopin_response_timer);
1008
1009         spin_lock_bh(&conn->nopin_timer_lock);
1010         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1011         spin_unlock_bh(&conn->nopin_timer_lock);
1012 }
1013
1014 static void iscsit_handle_nopin_timeout(unsigned long data)
1015 {
1016         struct iscsi_conn *conn = (struct iscsi_conn *) data;
1017
1018         iscsit_inc_conn_usage_count(conn);
1019
1020         spin_lock_bh(&conn->nopin_timer_lock);
1021         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1022                 spin_unlock_bh(&conn->nopin_timer_lock);
1023                 iscsit_dec_conn_usage_count(conn);
1024                 return;
1025         }
1026         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1027         spin_unlock_bh(&conn->nopin_timer_lock);
1028
1029         iscsit_add_nopin(conn, 1);
1030         iscsit_dec_conn_usage_count(conn);
1031 }
1032
1033 /*
1034  * Called with conn->nopin_timer_lock held.
1035  */
1036 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1037 {
1038         struct iscsi_session *sess = conn->sess;
1039         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1040         /*
1041         * NOPIN timeout is disabled.
1042          */
1043         if (!na->nopin_timeout)
1044                 return;
1045
1046         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1047                 return;
1048
1049         init_timer(&conn->nopin_timer);
1050         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1051         conn->nopin_timer.data = (unsigned long)conn;
1052         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1053         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1054         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1055         add_timer(&conn->nopin_timer);
1056
1057         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1058                 " interval\n", conn->cid, na->nopin_timeout);
1059 }
1060
1061 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1062 {
1063         struct iscsi_session *sess = conn->sess;
1064         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1065         /*
1066          * NOPIN timeout is disabled..
1067          */
1068         if (!na->nopin_timeout)
1069                 return;
1070
1071         spin_lock_bh(&conn->nopin_timer_lock);
1072         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1073                 spin_unlock_bh(&conn->nopin_timer_lock);
1074                 return;
1075         }
1076
1077         init_timer(&conn->nopin_timer);
1078         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1079         conn->nopin_timer.data = (unsigned long)conn;
1080         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1081         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1082         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1083         add_timer(&conn->nopin_timer);
1084
1085         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1086                         " interval\n", conn->cid, na->nopin_timeout);
1087         spin_unlock_bh(&conn->nopin_timer_lock);
1088 }
1089
1090 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1091 {
1092         spin_lock_bh(&conn->nopin_timer_lock);
1093         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1094                 spin_unlock_bh(&conn->nopin_timer_lock);
1095                 return;
1096         }
1097         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1098         spin_unlock_bh(&conn->nopin_timer_lock);
1099
1100         del_timer_sync(&conn->nopin_timer);
1101
1102         spin_lock_bh(&conn->nopin_timer_lock);
1103         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1104         spin_unlock_bh(&conn->nopin_timer_lock);
1105 }
1106
1107 int iscsit_send_tx_data(
1108         struct iscsi_cmd *cmd,
1109         struct iscsi_conn *conn,
1110         int use_misc)
1111 {
1112         int tx_sent, tx_size;
1113         u32 iov_count;
1114         struct kvec *iov;
1115
1116 send_data:
1117         tx_size = cmd->tx_size;
1118
1119         if (!use_misc) {
1120                 iov = &cmd->iov_data[0];
1121                 iov_count = cmd->iov_data_count;
1122         } else {
1123                 iov = &cmd->iov_misc[0];
1124                 iov_count = cmd->iov_misc_count;
1125         }
1126
1127         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1128         if (tx_size != tx_sent) {
1129                 if (tx_sent == -EAGAIN) {
1130                         pr_err("tx_data() returned -EAGAIN\n");
1131                         goto send_data;
1132                 } else
1133                         return -1;
1134         }
1135         cmd->tx_size = 0;
1136
1137         return 0;
1138 }
1139
1140 int iscsit_fe_sendpage_sg(
1141         struct iscsi_cmd *cmd,
1142         struct iscsi_conn *conn)
1143 {
1144         struct scatterlist *sg = cmd->first_data_sg;
1145         struct kvec iov;
1146         u32 tx_hdr_size, data_len;
1147         u32 offset = cmd->first_data_sg_off;
1148         int tx_sent, iov_off;
1149
1150 send_hdr:
1151         tx_hdr_size = ISCSI_HDR_LEN;
1152         if (conn->conn_ops->HeaderDigest)
1153                 tx_hdr_size += ISCSI_CRC_LEN;
1154
1155         iov.iov_base = cmd->pdu;
1156         iov.iov_len = tx_hdr_size;
1157
1158         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1159         if (tx_hdr_size != tx_sent) {
1160                 if (tx_sent == -EAGAIN) {
1161                         pr_err("tx_data() returned -EAGAIN\n");
1162                         goto send_hdr;
1163                 }
1164                 return -1;
1165         }
1166
1167         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1168         /*
1169          * Set iov_off used by padding and data digest tx_data() calls below
1170          * in order to determine proper offset into cmd->iov_data[]
1171          */
1172         if (conn->conn_ops->DataDigest) {
1173                 data_len -= ISCSI_CRC_LEN;
1174                 if (cmd->padding)
1175                         iov_off = (cmd->iov_data_count - 2);
1176                 else
1177                         iov_off = (cmd->iov_data_count - 1);
1178         } else {
1179                 iov_off = (cmd->iov_data_count - 1);
1180         }
1181         /*
1182          * Perform sendpage() for each page in the scatterlist
1183          */
1184         while (data_len) {
1185                 u32 space = (sg->length - offset);
1186                 u32 sub_len = min_t(u32, data_len, space);
1187 send_pg:
1188                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1189                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1190                 if (tx_sent != sub_len) {
1191                         if (tx_sent == -EAGAIN) {
1192                                 pr_err("tcp_sendpage() returned"
1193                                                 " -EAGAIN\n");
1194                                 goto send_pg;
1195                         }
1196
1197                         pr_err("tcp_sendpage() failure: %d\n",
1198                                         tx_sent);
1199                         return -1;
1200                 }
1201
1202                 data_len -= sub_len;
1203                 offset = 0;
1204                 sg = sg_next(sg);
1205         }
1206
1207 send_padding:
1208         if (cmd->padding) {
1209                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1210
1211                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1212                 if (cmd->padding != tx_sent) {
1213                         if (tx_sent == -EAGAIN) {
1214                                 pr_err("tx_data() returned -EAGAIN\n");
1215                                 goto send_padding;
1216                         }
1217                         return -1;
1218                 }
1219         }
1220
1221 send_datacrc:
1222         if (conn->conn_ops->DataDigest) {
1223                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1224
1225                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1226                 if (ISCSI_CRC_LEN != tx_sent) {
1227                         if (tx_sent == -EAGAIN) {
1228                                 pr_err("tx_data() returned -EAGAIN\n");
1229                                 goto send_datacrc;
1230                         }
1231                         return -1;
1232                 }
1233         }
1234
1235         return 0;
1236 }
1237
1238 /*
1239  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1240  *      back to the Initiator when an expection condition occurs with the
1241  *      errors set in status_class and status_detail.
1242  *
1243  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1244  *      Returns:        0 on success, -1 on error.
1245  */
1246 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1247 {
1248         struct iscsi_login_rsp *hdr;
1249         struct iscsi_login *login = conn->conn_login;
1250
1251         login->login_failed = 1;
1252         iscsit_collect_login_stats(conn, status_class, status_detail);
1253
1254         hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1255         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1256         hdr->status_class       = status_class;
1257         hdr->status_detail      = status_detail;
1258         hdr->itt                = conn->login_itt;
1259
1260         return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1261 }
1262
1263 void iscsit_print_session_params(struct iscsi_session *sess)
1264 {
1265         struct iscsi_conn *conn;
1266
1267         pr_debug("-----------------------------[Session Params for"
1268                 " SID: %u]-----------------------------\n", sess->sid);
1269         spin_lock_bh(&sess->conn_lock);
1270         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1271                 iscsi_dump_conn_ops(conn->conn_ops);
1272         spin_unlock_bh(&sess->conn_lock);
1273
1274         iscsi_dump_sess_ops(sess->sess_ops);
1275 }
1276
1277 static int iscsit_do_rx_data(
1278         struct iscsi_conn *conn,
1279         struct iscsi_data_count *count)
1280 {
1281         int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
1282         struct kvec *iov_p;
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
1290         iov_p = count->iov;
1291         iov_len = count->iov_count;
1292
1293         while (total_rx < data) {
1294                 rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
1295                                         (data - total_rx), MSG_WAITALL);
1296                 if (rx_loop <= 0) {
1297                         pr_debug("rx_loop: %d total_rx: %d\n",
1298                                 rx_loop, total_rx);
1299                         return rx_loop;
1300                 }
1301                 total_rx += rx_loop;
1302                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1303                                 rx_loop, total_rx, data);
1304         }
1305
1306         return total_rx;
1307 }
1308
1309 static int iscsit_do_tx_data(
1310         struct iscsi_conn *conn,
1311         struct iscsi_data_count *count)
1312 {
1313         int data = count->data_length, total_tx = 0, tx_loop = 0, iov_len;
1314         struct kvec *iov_p;
1315         struct msghdr msg;
1316
1317         if (!conn || !conn->sock || !conn->conn_ops)
1318                 return -1;
1319
1320         if (data <= 0) {
1321                 pr_err("Data length is: %d\n", data);
1322                 return -1;
1323         }
1324
1325         memset(&msg, 0, sizeof(struct msghdr));
1326
1327         iov_p = count->iov;
1328         iov_len = count->iov_count;
1329
1330         while (total_tx < data) {
1331                 tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1332                                         (data - total_tx));
1333                 if (tx_loop <= 0) {
1334                         pr_debug("tx_loop: %d total_tx %d\n",
1335                                 tx_loop, total_tx);
1336                         return tx_loop;
1337                 }
1338                 total_tx += tx_loop;
1339                 pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1340                                         tx_loop, total_tx, data);
1341         }
1342
1343         return total_tx;
1344 }
1345
1346 int rx_data(
1347         struct iscsi_conn *conn,
1348         struct kvec *iov,
1349         int iov_count,
1350         int data)
1351 {
1352         struct iscsi_data_count c;
1353
1354         if (!conn || !conn->sock || !conn->conn_ops)
1355                 return -1;
1356
1357         memset(&c, 0, sizeof(struct iscsi_data_count));
1358         c.iov = iov;
1359         c.iov_count = iov_count;
1360         c.data_length = data;
1361         c.type = ISCSI_RX_DATA;
1362
1363         return iscsit_do_rx_data(conn, &c);
1364 }
1365
1366 int tx_data(
1367         struct iscsi_conn *conn,
1368         struct kvec *iov,
1369         int iov_count,
1370         int data)
1371 {
1372         struct iscsi_data_count c;
1373
1374         if (!conn || !conn->sock || !conn->conn_ops)
1375                 return -1;
1376
1377         memset(&c, 0, sizeof(struct iscsi_data_count));
1378         c.iov = iov;
1379         c.iov_count = iov_count;
1380         c.data_length = data;
1381         c.type = ISCSI_TX_DATA;
1382
1383         return iscsit_do_tx_data(conn, &c);
1384 }
1385
1386 void iscsit_collect_login_stats(
1387         struct iscsi_conn *conn,
1388         u8 status_class,
1389         u8 status_detail)
1390 {
1391         struct iscsi_param *intrname = NULL;
1392         struct iscsi_tiqn *tiqn;
1393         struct iscsi_login_stats *ls;
1394
1395         tiqn = iscsit_snmp_get_tiqn(conn);
1396         if (!tiqn)
1397                 return;
1398
1399         ls = &tiqn->login_stats;
1400
1401         spin_lock(&ls->lock);
1402         if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1403             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1404                 /* We already have the failure info for this login */
1405                 spin_unlock(&ls->lock);
1406                 return;
1407         }
1408
1409         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1410                 ls->accepts++;
1411         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1412                 ls->redirects++;
1413                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1414         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1415                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1416                 ls->authenticate_fails++;
1417                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1418         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1419                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1420                 ls->authorize_fails++;
1421                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1422         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1423                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1424                 ls->negotiate_fails++;
1425                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1426         } else {
1427                 ls->other_fails++;
1428                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1429         }
1430
1431         /* Save initiator name, ip address and time, if it is a failed login */
1432         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1433                 if (conn->param_list)
1434                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1435                                                              conn->param_list);
1436                 strcpy(ls->last_intr_fail_name,
1437                        (intrname ? intrname->value : "Unknown"));
1438
1439                 ls->last_intr_fail_ip_family = conn->login_family;
1440
1441                 snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1442                                 "%s", conn->login_ip);
1443                 ls->last_fail_time = get_jiffies_64();
1444         }
1445
1446         spin_unlock(&ls->lock);
1447 }
1448
1449 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1450 {
1451         struct iscsi_portal_group *tpg;
1452
1453         if (!conn || !conn->sess)
1454                 return NULL;
1455
1456         tpg = conn->sess->tpg;
1457         if (!tpg)
1458                 return NULL;
1459
1460         if (!tpg->tpg_tiqn)
1461                 return NULL;
1462
1463         return tpg->tpg_tiqn;
1464 }