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
  28 #include "iscsi_target_core.h"
  29 #include "iscsi_target_parameters.h"
  30 #include "iscsi_target_seq_pdu_list.h"
  31 #include "iscsi_target_datain_values.h"
  32 #include "iscsi_target_erl0.h"
  33 #include "iscsi_target_erl1.h"
  34 #include "iscsi_target_erl2.h"
  35 #include "iscsi_target_tpg.h"
  36 #include "iscsi_target_tq.h"
  37 #include "iscsi_target_util.h"
  38 #include "iscsi_target.h"
  39
  40 #define PRINT_BUFF(buff, len)                                   \
  41 {                                                               \
  42         int zzz;                                                \
  43                                                                 \
  44         pr_debug("%d:\n", __LINE__);                            \
  45         for (zzz = 0; zzz < len; zzz++) {                       \
  46                 if (zzz % 16 == 0) {                            \
  47                         if (zzz)                                \
  48                                 pr_debug("\n");                 \
  49                         pr_debug("%4i: ", zzz);                 \
  50                 }                                               \
  51                 pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  52         }                                                       \
  53         if ((len + 1) % 16)                                     \
  54                 pr_debug("\n");                                 \
  55 }
  56
  57 extern struct list_head g_tiqn_list;
  58 extern spinlock_t tiqn_lock;
  59
  60 /*
  61  *      Called with cmd->r2t_lock held.
  62  */
  63 int iscsit_add_r2t_to_list(
  64         struct iscsi_cmd *cmd,
  65         u32 offset,
  66         u32 xfer_len,
  67         int recovery,
  68         u32 r2t_sn)
  69 {
  70         struct iscsi_r2t *r2t;
  71
  72         r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  73         if (!r2t) {
  74                 pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  75                 return -1;
  76         }
  77         INIT_LIST_HEAD(&r2t->r2t_list);
  78
  79         r2t->recovery_r2t = recovery;
  80         r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  81         r2t->offset = offset;
  82         r2t->xfer_len = xfer_len;
  83         list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  84         spin_unlock_bh(&cmd->r2t_lock);
  85
  86         iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  87
  88         spin_lock_bh(&cmd->r2t_lock);
  89         return 0;
  90 }
  91
  92 struct iscsi_r2t *iscsit_get_r2t_for_eos(
  93         struct iscsi_cmd *cmd,
  94         u32 offset,
  95         u32 length)
  96 {
  97         struct iscsi_r2t *r2t;
  98
  99         spin_lock_bh(&cmd->r2t_lock);
 100         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 101                 if ((r2t->offset <= offset) &&
 102                     (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 103                         spin_unlock_bh(&cmd->r2t_lock);
 104                         return r2t;
 105                 }
 106         }
 107         spin_unlock_bh(&cmd->r2t_lock);
 108
 109         pr_err("Unable to locate R2T for Offset: %u, Length:"
 110                         " %u\n", offset, length);
 111         return NULL;
 112 }
 113
 114 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 115 {
 116         struct iscsi_r2t *r2t;
 117
 118         spin_lock_bh(&cmd->r2t_lock);
 119         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 120                 if (!r2t->sent_r2t) {
 121                         spin_unlock_bh(&cmd->r2t_lock);
 122                         return r2t;
 123                 }
 124         }
 125         spin_unlock_bh(&cmd->r2t_lock);
 126
 127         pr_err("Unable to locate next R2T to send for ITT:"
 128                         " 0x%08x.\n", cmd->init_task_tag);
 129         return NULL;
 130 }
 131
 132 /*
 133  *      Called with cmd->r2t_lock held.
 134  */
 135 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 136 {
 137         list_del(&r2t->r2t_list);
 138         kmem_cache_free(lio_r2t_cache, r2t);
 139 }
 140
 141 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 142 {
 143         struct iscsi_r2t *r2t, *r2t_tmp;
 144
 145         spin_lock_bh(&cmd->r2t_lock);
 146         list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 147                 iscsit_free_r2t(r2t, cmd);
 148         spin_unlock_bh(&cmd->r2t_lock);
 149 }
 150
 151 /*
 152  * May be called from software interrupt (timer) context for allocating
 153  * iSCSI NopINs.
 154  */
 155 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, gfp_t gfp_mask)
 156 {
 157         struct iscsi_cmd *cmd;
 158
 159         cmd = kmem_cache_zalloc(lio_cmd_cache, gfp_mask);
 160         if (!cmd) {
 161                 pr_err("Unable to allocate memory for struct iscsi_cmd.\n");
 162                 return NULL;
 163         }
 164
 165         cmd->conn       = conn;
 166         INIT_LIST_HEAD(&cmd->i_conn_node);
 167         INIT_LIST_HEAD(&cmd->datain_list);
 168         INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 169         init_completion(&cmd->reject_comp);
 170         spin_lock_init(&cmd->datain_lock);
 171         spin_lock_init(&cmd->dataout_timeout_lock);
 172         spin_lock_init(&cmd->istate_lock);
 173         spin_lock_init(&cmd->error_lock);
 174         spin_lock_init(&cmd->r2t_lock);
 175
 176         return cmd;
 177 }
 178
 179 int iscsit_decide_list_to_build(
 180         struct iscsi_cmd *cmd,
 181         u32 immediate_data_length)
 182 {
 183         struct iscsi_build_list bl;
 184         struct iscsi_conn *conn = cmd->conn;
 185         struct iscsi_session *sess = conn->sess;
 186         struct iscsi_node_attrib *na;
 187
 188         if (sess->sess_ops->DataSequenceInOrder &&
 189             sess->sess_ops->DataPDUInOrder)
 190                 return 0;
 191
 192         if (cmd->data_direction == DMA_NONE)
 193                 return 0;
 194
 195         na = iscsit_tpg_get_node_attrib(sess);
 196         memset(&bl, 0, sizeof(struct iscsi_build_list));
 197
 198         if (cmd->data_direction == DMA_FROM_DEVICE) {
 199                 bl.data_direction = ISCSI_PDU_READ;
 200                 bl.type = PDULIST_NORMAL;
 201                 if (na->random_datain_pdu_offsets)
 202                         bl.randomize |= RANDOM_DATAIN_PDU_OFFSETS;
 203                 if (na->random_datain_seq_offsets)
 204                         bl.randomize |= RANDOM_DATAIN_SEQ_OFFSETS;
 205         } else {
 206                 bl.data_direction = ISCSI_PDU_WRITE;
 207                 bl.immediate_data_length = immediate_data_length;
 208                 if (na->random_r2t_offsets)
 209                         bl.randomize |= RANDOM_R2T_OFFSETS;
 210
 211                 if (!cmd->immediate_data && !cmd->unsolicited_data)
 212                         bl.type = PDULIST_NORMAL;
 213                 else if (cmd->immediate_data && !cmd->unsolicited_data)
 214                         bl.type = PDULIST_IMMEDIATE;
 215                 else if (!cmd->immediate_data && cmd->unsolicited_data)
 216                         bl.type = PDULIST_UNSOLICITED;
 217                 else if (cmd->immediate_data && cmd->unsolicited_data)
 218                         bl.type = PDULIST_IMMEDIATE_AND_UNSOLICITED;
 219         }
 220
 221         return iscsit_do_build_list(cmd, &bl);
 222 }
 223
 224 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 225         struct iscsi_cmd *cmd,
 226         u32 seq_send_order)
 227 {
 228         u32 i;
 229
 230         for (i = 0; i < cmd->seq_count; i++)
 231                 if (cmd->seq_list[i].seq_send_order == seq_send_order)
 232                         return &cmd->seq_list[i];
 233
 234         return NULL;
 235 }
 236
 237 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 238 {
 239         u32 i;
 240
 241         if (!cmd->seq_list) {
 242                 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 243                 return NULL;
 244         }
 245
 246         for (i = 0; i < cmd->seq_count; i++) {
 247                 if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 248                         continue;
 249                 if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 250                         cmd->seq_send_order++;
 251                         return &cmd->seq_list[i];
 252                 }
 253         }
 254
 255         return NULL;
 256 }
 257
 258 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 259         struct iscsi_cmd *cmd,
 260         u32 r2t_sn)
 261 {
 262         struct iscsi_r2t *r2t;
 263
 264         spin_lock_bh(&cmd->r2t_lock);
 265         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 266                 if (r2t->r2t_sn == r2t_sn) {
 267                         spin_unlock_bh(&cmd->r2t_lock);
 268                         return r2t;
 269                 }
 270         }
 271         spin_unlock_bh(&cmd->r2t_lock);
 272
 273         return NULL;
 274 }
 275
 276 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 277 {
 278         int ret;
 279
 280         /*
 281          * This is the proper method of checking received CmdSN against
 282          * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 283          * or order CmdSNs due to multiple connection sessions and/or
 284          * CRC failures.
 285          */
 286         if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) {
 287                 pr_err("Received CmdSN: 0x%08x is greater than"
 288                        " MaxCmdSN: 0x%08x, protocol error.\n", cmdsn,
 289                        sess->max_cmd_sn);
 290                 ret = CMDSN_ERROR_CANNOT_RECOVER;
 291
 292         } else if (cmdsn == sess->exp_cmd_sn) {
 293                 sess->exp_cmd_sn++;
 294                 pr_debug("Received CmdSN matches ExpCmdSN,"
 295                       " incremented ExpCmdSN to: 0x%08x\n",
 296                       sess->exp_cmd_sn);
 297                 ret = CMDSN_NORMAL_OPERATION;
 298
 299         } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 300                 pr_debug("Received CmdSN: 0x%08x is greater"
 301                       " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 302                       cmdsn, sess->exp_cmd_sn);
 303                 ret = CMDSN_HIGHER_THAN_EXP;
 304
 305         } else {
 306                 pr_err("Received CmdSN: 0x%08x is less than"
 307                        " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 308                        sess->exp_cmd_sn);
 309                 ret = CMDSN_LOWER_THAN_EXP;
 310         }
 311
 312         return ret;
 313 }
 314
 315 /*
 316  * Commands may be received out of order if MC/S is in use.
 317  * Ensure they are executed in CmdSN order.
 318  */
 319 int iscsit_sequence_cmd(
 320         struct iscsi_conn *conn,
 321         struct iscsi_cmd *cmd,
 322         u32 cmdsn)
 323 {
 324         int ret;
 325         int cmdsn_ret;
 326
 327         mutex_lock(&conn->sess->cmdsn_mutex);
 328
 329         cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, cmdsn);
 330         switch (cmdsn_ret) {
 331         case CMDSN_NORMAL_OPERATION:
 332                 ret = iscsit_execute_cmd(cmd, 0);
 333                 if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 334                         iscsit_execute_ooo_cmdsns(conn->sess);
 335                 break;
 336         case CMDSN_HIGHER_THAN_EXP:
 337                 ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, cmdsn);
 338                 break;
 339         case CMDSN_LOWER_THAN_EXP:
 340                 cmd->i_state = ISTATE_REMOVE;
 341                 iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 342                 ret = cmdsn_ret;
 343                 break;
 344         default:
 345                 ret = cmdsn_ret;
 346                 break;
 347         }
 348         mutex_unlock(&conn->sess->cmdsn_mutex);
 349
 350         return ret;
 351 }
 352
 353 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 354 {
 355         struct iscsi_conn *conn = cmd->conn;
 356         struct se_cmd *se_cmd = &cmd->se_cmd;
 357         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 358         u32 payload_length = ntoh24(hdr->dlength);
 359
 360         if (conn->sess->sess_ops->InitialR2T) {
 361                 pr_err("Received unexpected unsolicited data"
 362                         " while InitialR2T=Yes, protocol error.\n");
 363                 transport_send_check_condition_and_sense(se_cmd,
 364                                 TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 365                 return -1;
 366         }
 367
 368         if ((cmd->first_burst_len + payload_length) >
 369              conn->sess->sess_ops->FirstBurstLength) {
 370                 pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 371                         " for this Unsolicited DataOut Burst.\n",
 372                         (cmd->first_burst_len + payload_length),
 373                                 conn->sess->sess_ops->FirstBurstLength);
 374                 transport_send_check_condition_and_sense(se_cmd,
 375                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 376                 return -1;
 377         }
 378
 379         if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 380                 return 0;
 381
 382         if (((cmd->first_burst_len + payload_length) != cmd->data_length) &&
 383             ((cmd->first_burst_len + payload_length) !=
 384               conn->sess->sess_ops->FirstBurstLength)) {
 385                 pr_err("Unsolicited non-immediate data received %u"
 386                         " does not equal FirstBurstLength: %u, and does"
 387                         " not equal ExpXferLen %u.\n",
 388                         (cmd->first_burst_len + payload_length),
 389                         conn->sess->sess_ops->FirstBurstLength, cmd->data_length);
 390                 transport_send_check_condition_and_sense(se_cmd,
 391                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 392                 return -1;
 393         }
 394         return 0;
 395 }
 396
 397 struct iscsi_cmd *iscsit_find_cmd_from_itt(
 398         struct iscsi_conn *conn,
 399         u32 init_task_tag)
 400 {
 401         struct iscsi_cmd *cmd;
 402
 403         spin_lock_bh(&conn->cmd_lock);
 404         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 405                 if (cmd->init_task_tag == init_task_tag) {
 406                         spin_unlock_bh(&conn->cmd_lock);
 407                         return cmd;
 408                 }
 409         }
 410         spin_unlock_bh(&conn->cmd_lock);
 411
 412         pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 413                         init_task_tag, conn->cid);
 414         return NULL;
 415 }
 416
 417 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 418         struct iscsi_conn *conn,
 419         u32 init_task_tag,
 420         u32 length)
 421 {
 422         struct iscsi_cmd *cmd;
 423
 424         spin_lock_bh(&conn->cmd_lock);
 425         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 426                 if (cmd->init_task_tag == init_task_tag) {
 427                         spin_unlock_bh(&conn->cmd_lock);
 428                         return cmd;
 429                 }
 430         }
 431         spin_unlock_bh(&conn->cmd_lock);
 432
 433         pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 434                         " dumping payload\n", init_task_tag, conn->cid);
 435         if (length)
 436                 iscsit_dump_data_payload(conn, length, 1);
 437
 438         return NULL;
 439 }
 440
 441 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 442         struct iscsi_conn *conn,
 443         u32 targ_xfer_tag)
 444 {
 445         struct iscsi_cmd *cmd = NULL;
 446
 447         spin_lock_bh(&conn->cmd_lock);
 448         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 449                 if (cmd->targ_xfer_tag == targ_xfer_tag) {
 450                         spin_unlock_bh(&conn->cmd_lock);
 451                         return cmd;
 452                 }
 453         }
 454         spin_unlock_bh(&conn->cmd_lock);
 455
 456         pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 457                         targ_xfer_tag, conn->cid);
 458         return NULL;
 459 }
 460
 461 int iscsit_find_cmd_for_recovery(
 462         struct iscsi_session *sess,
 463         struct iscsi_cmd **cmd_ptr,
 464         struct iscsi_conn_recovery **cr_ptr,
 465         u32 init_task_tag)
 466 {
 467         struct iscsi_cmd *cmd = NULL;
 468         struct iscsi_conn_recovery *cr;
 469         /*
 470          * Scan through the inactive connection recovery list's command list.
 471          * If init_task_tag matches the command is still alligent.
 472          */
 473         spin_lock(&sess->cr_i_lock);
 474         list_for_each_entry(cr, &sess->cr_inactive_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_i_lock);
 480
 481                                 *cr_ptr = cr;
 482                                 *cmd_ptr = cmd;
 483                                 return -2;
 484                         }
 485                 }
 486                 spin_unlock(&cr->conn_recovery_cmd_lock);
 487         }
 488         spin_unlock(&sess->cr_i_lock);
 489         /*
 490          * Scan through the active connection recovery list's command list.
 491          * If init_task_tag matches the command is ready to be reassigned.
 492          */
 493         spin_lock(&sess->cr_a_lock);
 494         list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 495                 spin_lock(&cr->conn_recovery_cmd_lock);
 496                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 497                         if (cmd->init_task_tag == init_task_tag) {
 498                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 499                                 spin_unlock(&sess->cr_a_lock);
 500
 501                                 *cr_ptr = cr;
 502                                 *cmd_ptr = cmd;
 503                                 return 0;
 504                         }
 505                 }
 506                 spin_unlock(&cr->conn_recovery_cmd_lock);
 507         }
 508         spin_unlock(&sess->cr_a_lock);
 509
 510         return -1;
 511 }
 512
 513 void iscsit_add_cmd_to_immediate_queue(
 514         struct iscsi_cmd *cmd,
 515         struct iscsi_conn *conn,
 516         u8 state)
 517 {
 518         struct iscsi_queue_req *qr;
 519
 520         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 521         if (!qr) {
 522                 pr_err("Unable to allocate memory for"
 523                                 " struct iscsi_queue_req\n");
 524                 return;
 525         }
 526         INIT_LIST_HEAD(&qr->qr_list);
 527         qr->cmd = cmd;
 528         qr->state = state;
 529
 530         spin_lock_bh(&conn->immed_queue_lock);
 531         list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 532         atomic_inc(&cmd->immed_queue_count);
 533         atomic_set(&conn->check_immediate_queue, 1);
 534         spin_unlock_bh(&conn->immed_queue_lock);
 535
 536         wake_up_process(conn->thread_set->tx_thread);
 537 }
 538
 539 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 540 {
 541         struct iscsi_queue_req *qr;
 542
 543         spin_lock_bh(&conn->immed_queue_lock);
 544         if (list_empty(&conn->immed_queue_list)) {
 545                 spin_unlock_bh(&conn->immed_queue_lock);
 546                 return NULL;
 547         }
 548         list_for_each_entry(qr, &conn->immed_queue_list, qr_list)
 549                 break;
 550
 551         list_del(&qr->qr_list);
 552         if (qr->cmd)
 553                 atomic_dec(&qr->cmd->immed_queue_count);
 554         spin_unlock_bh(&conn->immed_queue_lock);
 555
 556         return qr;
 557 }
 558
 559 static void iscsit_remove_cmd_from_immediate_queue(
 560         struct iscsi_cmd *cmd,
 561         struct iscsi_conn *conn)
 562 {
 563         struct iscsi_queue_req *qr, *qr_tmp;
 564
 565         spin_lock_bh(&conn->immed_queue_lock);
 566         if (!atomic_read(&cmd->immed_queue_count)) {
 567                 spin_unlock_bh(&conn->immed_queue_lock);
 568                 return;
 569         }
 570
 571         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 572                 if (qr->cmd != cmd)
 573                         continue;
 574
 575                 atomic_dec(&qr->cmd->immed_queue_count);
 576                 list_del(&qr->qr_list);
 577                 kmem_cache_free(lio_qr_cache, qr);
 578         }
 579         spin_unlock_bh(&conn->immed_queue_lock);
 580
 581         if (atomic_read(&cmd->immed_queue_count)) {
 582                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 583                         cmd->init_task_tag,
 584                         atomic_read(&cmd->immed_queue_count));
 585         }
 586 }
 587
 588 void iscsit_add_cmd_to_response_queue(
 589         struct iscsi_cmd *cmd,
 590         struct iscsi_conn *conn,
 591         u8 state)
 592 {
 593         struct iscsi_queue_req *qr;
 594
 595         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 596         if (!qr) {
 597                 pr_err("Unable to allocate memory for"
 598                         " struct iscsi_queue_req\n");
 599                 return;
 600         }
 601         INIT_LIST_HEAD(&qr->qr_list);
 602         qr->cmd = cmd;
 603         qr->state = state;
 604
 605         spin_lock_bh(&conn->response_queue_lock);
 606         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 607         atomic_inc(&cmd->response_queue_count);
 608         spin_unlock_bh(&conn->response_queue_lock);
 609
 610         wake_up_process(conn->thread_set->tx_thread);
 611 }
 612
 613 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 614 {
 615         struct iscsi_queue_req *qr;
 616
 617         spin_lock_bh(&conn->response_queue_lock);
 618         if (list_empty(&conn->response_queue_list)) {
 619                 spin_unlock_bh(&conn->response_queue_lock);
 620                 return NULL;
 621         }
 622
 623         list_for_each_entry(qr, &conn->response_queue_list, qr_list)
 624                 break;
 625
 626         list_del(&qr->qr_list);
 627         if (qr->cmd)
 628                 atomic_dec(&qr->cmd->response_queue_count);
 629         spin_unlock_bh(&conn->response_queue_lock);
 630
 631         return qr;
 632 }
 633
 634 static void iscsit_remove_cmd_from_response_queue(
 635         struct iscsi_cmd *cmd,
 636         struct iscsi_conn *conn)
 637 {
 638         struct iscsi_queue_req *qr, *qr_tmp;
 639
 640         spin_lock_bh(&conn->response_queue_lock);
 641         if (!atomic_read(&cmd->response_queue_count)) {
 642                 spin_unlock_bh(&conn->response_queue_lock);
 643                 return;
 644         }
 645
 646         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 647                                 qr_list) {
 648                 if (qr->cmd != cmd)
 649                         continue;
 650
 651                 atomic_dec(&qr->cmd->response_queue_count);
 652                 list_del(&qr->qr_list);
 653                 kmem_cache_free(lio_qr_cache, qr);
 654         }
 655         spin_unlock_bh(&conn->response_queue_lock);
 656
 657         if (atomic_read(&cmd->response_queue_count)) {
 658                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 659                         cmd->init_task_tag,
 660                         atomic_read(&cmd->response_queue_count));
 661         }
 662 }
 663
 664 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 665 {
 666         struct iscsi_queue_req *qr, *qr_tmp;
 667
 668         spin_lock_bh(&conn->immed_queue_lock);
 669         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 670                 list_del(&qr->qr_list);
 671                 if (qr->cmd)
 672                         atomic_dec(&qr->cmd->immed_queue_count);
 673
 674                 kmem_cache_free(lio_qr_cache, qr);
 675         }
 676         spin_unlock_bh(&conn->immed_queue_lock);
 677
 678         spin_lock_bh(&conn->response_queue_lock);
 679         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 680                         qr_list) {
 681                 list_del(&qr->qr_list);
 682                 if (qr->cmd)
 683                         atomic_dec(&qr->cmd->response_queue_count);
 684
 685                 kmem_cache_free(lio_qr_cache, qr);
 686         }
 687         spin_unlock_bh(&conn->response_queue_lock);
 688 }
 689
 690 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 691 {
 692         struct iscsi_conn *conn = cmd->conn;
 693         int i;
 694
 695         iscsit_free_r2ts_from_list(cmd);
 696         iscsit_free_all_datain_reqs(cmd);
 697
 698         kfree(cmd->buf_ptr);
 699         kfree(cmd->pdu_list);
 700         kfree(cmd->seq_list);
 701         kfree(cmd->tmr_req);
 702         kfree(cmd->iov_data);
 703
 704         for (i = 0; i < cmd->t_mem_sg_nents; i++)
 705                 __free_page(sg_page(&cmd->t_mem_sg[i]));
 706
 707         kfree(cmd->t_mem_sg);
 708
 709         if (conn) {
 710                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 711                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 712         }
 713
 714         kmem_cache_free(lio_cmd_cache, cmd);
 715 }
 716
 717 void iscsit_free_cmd(struct iscsi_cmd *cmd)
 718 {
 719         /*
 720          * Determine if a struct se_cmd is assoicated with
 721          * this struct iscsi_cmd.
 722          */
 723         switch (cmd->iscsi_opcode) {
 724         case ISCSI_OP_SCSI_CMD:
 725         case ISCSI_OP_SCSI_TMFUNC:
 726                 transport_generic_free_cmd(&cmd->se_cmd, 1);
 727                 break;
 728         case ISCSI_OP_REJECT:
 729                 /*
 730                  * Handle special case for REJECT when iscsi_add_reject*() has
 731                  * overwritten the original iscsi_opcode assignment, and the
 732                  * associated cmd->se_cmd needs to be released.
 733                  */
 734                 if (cmd->se_cmd.se_tfo != NULL) {
 735                         transport_generic_free_cmd(&cmd->se_cmd, 1);
 736                         break;
 737                 }
 738                 /* Fall-through */
 739         default:
 740                 iscsit_release_cmd(cmd);
 741                 break;
 742         }
 743 }
 744
 745 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 746 {
 747         spin_lock_bh(&sess->session_usage_lock);
 748         if (sess->session_usage_count != 0) {
 749                 sess->session_waiting_on_uc = 1;
 750                 spin_unlock_bh(&sess->session_usage_lock);
 751                 if (in_interrupt())
 752                         return 2;
 753
 754                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 755                 return 1;
 756         }
 757         spin_unlock_bh(&sess->session_usage_lock);
 758
 759         return 0;
 760 }
 761
 762 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 763 {
 764         spin_lock_bh(&sess->session_usage_lock);
 765         sess->session_usage_count--;
 766
 767         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 768                 complete(&sess->session_waiting_on_uc_comp);
 769
 770         spin_unlock_bh(&sess->session_usage_lock);
 771 }
 772
 773 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 774 {
 775         spin_lock_bh(&sess->session_usage_lock);
 776         sess->session_usage_count++;
 777         spin_unlock_bh(&sess->session_usage_lock);
 778 }
 779
 780 /*
 781  *      Setup conn->if_marker and conn->of_marker values based upon
 782  *      the initial marker-less interval. (see iSCSI v19 A.2)
 783  */
 784 int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 785 {
 786         int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 787         /*
 788          * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 789          */
 790         u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 791         u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 792
 793         if (conn->conn_ops->OFMarker) {
 794                 /*
 795                  * Account for the first Login Command received not
 796                  * via iscsi_recv_msg().
 797                  */
 798                 conn->of_marker += ISCSI_HDR_LEN;
 799                 if (conn->of_marker <= OFMarkInt) {
 800                         conn->of_marker = (OFMarkInt - conn->of_marker);
 801                 } else {
 802                         login_ofmarker_count = (conn->of_marker / OFMarkInt);
 803                         next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 804                                         (login_ofmarker_count * MARKER_SIZE);
 805                         conn->of_marker = (next_marker - conn->of_marker);
 806                 }
 807                 conn->of_marker_offset = 0;
 808                 pr_debug("Setting OFMarker value to %u based on Initial"
 809                         " Markerless Interval.\n", conn->of_marker);
 810         }
 811
 812         if (conn->conn_ops->IFMarker) {
 813                 if (conn->if_marker <= IFMarkInt) {
 814                         conn->if_marker = (IFMarkInt - conn->if_marker);
 815                 } else {
 816                         login_ifmarker_count = (conn->if_marker / IFMarkInt);
 817                         next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 818                                         (login_ifmarker_count * MARKER_SIZE);
 819                         conn->if_marker = (next_marker - conn->if_marker);
 820                 }
 821                 pr_debug("Setting IFMarker value to %u based on Initial"
 822                         " Markerless Interval.\n", conn->if_marker);
 823         }
 824
 825         return 0;
 826 }
 827
 828 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 829 {
 830         struct iscsi_conn *conn;
 831
 832         spin_lock_bh(&sess->conn_lock);
 833         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 834                 if ((conn->cid == cid) &&
 835                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 836                         iscsit_inc_conn_usage_count(conn);
 837                         spin_unlock_bh(&sess->conn_lock);
 838                         return conn;
 839                 }
 840         }
 841         spin_unlock_bh(&sess->conn_lock);
 842
 843         return NULL;
 844 }
 845
 846 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 847 {
 848         struct iscsi_conn *conn;
 849
 850         spin_lock_bh(&sess->conn_lock);
 851         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 852                 if (conn->cid == cid) {
 853                         iscsit_inc_conn_usage_count(conn);
 854                         spin_lock(&conn->state_lock);
 855                         atomic_set(&conn->connection_wait_rcfr, 1);
 856                         spin_unlock(&conn->state_lock);
 857                         spin_unlock_bh(&sess->conn_lock);
 858                         return conn;
 859                 }
 860         }
 861         spin_unlock_bh(&sess->conn_lock);
 862
 863         return NULL;
 864 }
 865
 866 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 867 {
 868         spin_lock_bh(&conn->conn_usage_lock);
 869         if (conn->conn_usage_count != 0) {
 870                 conn->conn_waiting_on_uc = 1;
 871                 spin_unlock_bh(&conn->conn_usage_lock);
 872
 873                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 874                 return;
 875         }
 876         spin_unlock_bh(&conn->conn_usage_lock);
 877 }
 878
 879 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 880 {
 881         spin_lock_bh(&conn->conn_usage_lock);
 882         conn->conn_usage_count--;
 883
 884         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 885                 complete(&conn->conn_waiting_on_uc_comp);
 886
 887         spin_unlock_bh(&conn->conn_usage_lock);
 888 }
 889
 890 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 891 {
 892         spin_lock_bh(&conn->conn_usage_lock);
 893         conn->conn_usage_count++;
 894         spin_unlock_bh(&conn->conn_usage_lock);
 895 }
 896
 897 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 898 {
 899         u8 state;
 900         struct iscsi_cmd *cmd;
 901
 902         cmd = iscsit_allocate_cmd(conn, GFP_ATOMIC);
 903         if (!cmd)
 904                 return -1;
 905
 906         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 907         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 908                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 909         cmd->init_task_tag = 0xFFFFFFFF;
 910         spin_lock_bh(&conn->sess->ttt_lock);
 911         cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
 912                         0xFFFFFFFF;
 913         if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
 914                 cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
 915         spin_unlock_bh(&conn->sess->ttt_lock);
 916
 917         spin_lock_bh(&conn->cmd_lock);
 918         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 919         spin_unlock_bh(&conn->cmd_lock);
 920
 921         if (want_response)
 922                 iscsit_start_nopin_response_timer(conn);
 923         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 924
 925         return 0;
 926 }
 927
 928 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 929 {
 930         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 931
 932         iscsit_inc_conn_usage_count(conn);
 933
 934         spin_lock_bh(&conn->nopin_timer_lock);
 935         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 936                 spin_unlock_bh(&conn->nopin_timer_lock);
 937                 iscsit_dec_conn_usage_count(conn);
 938                 return;
 939         }
 940
 941         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 942                 " SID: %u, failing connection.\n", conn->cid,
 943                         conn->sess->sid);
 944         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 945         spin_unlock_bh(&conn->nopin_timer_lock);
 946
 947         {
 948         struct iscsi_portal_group *tpg = conn->sess->tpg;
 949         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 950
 951         if (tiqn) {
 952                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 953                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 954                                 conn->sess->sess_ops->InitiatorName);
 955                 tiqn->sess_err_stats.last_sess_failure_type =
 956                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 957                 tiqn->sess_err_stats.cxn_timeout_errors++;
 958                 conn->sess->conn_timeout_errors++;
 959                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 960         }
 961         }
 962
 963         iscsit_cause_connection_reinstatement(conn, 0);
 964         iscsit_dec_conn_usage_count(conn);
 965 }
 966
 967 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 968 {
 969         struct iscsi_session *sess = conn->sess;
 970         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 971
 972         spin_lock_bh(&conn->nopin_timer_lock);
 973         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 974                 spin_unlock_bh(&conn->nopin_timer_lock);
 975                 return;
 976         }
 977
 978         mod_timer(&conn->nopin_response_timer,
 979                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
 980         spin_unlock_bh(&conn->nopin_timer_lock);
 981 }
 982
 983 /*
 984  *      Called with conn->nopin_timer_lock held.
 985  */
 986 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
 987 {
 988         struct iscsi_session *sess = conn->sess;
 989         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 990
 991         spin_lock_bh(&conn->nopin_timer_lock);
 992         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
 993                 spin_unlock_bh(&conn->nopin_timer_lock);
 994                 return;
 995         }
 996
 997         init_timer(&conn->nopin_response_timer);
 998         conn->nopin_response_timer.expires =
 999                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
1000         conn->nopin_response_timer.data = (unsigned long)conn;
1001         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
1002         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
1003         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
1004         add_timer(&conn->nopin_response_timer);
1005
1006         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
1007                 " seconds\n", conn->cid, na->nopin_response_timeout);
1008         spin_unlock_bh(&conn->nopin_timer_lock);
1009 }
1010
1011 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
1012 {
1013         spin_lock_bh(&conn->nopin_timer_lock);
1014         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1015                 spin_unlock_bh(&conn->nopin_timer_lock);
1016                 return;
1017         }
1018         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1019         spin_unlock_bh(&conn->nopin_timer_lock);
1020
1021         del_timer_sync(&conn->nopin_response_timer);
1022
1023         spin_lock_bh(&conn->nopin_timer_lock);
1024         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1025         spin_unlock_bh(&conn->nopin_timer_lock);
1026 }
1027
1028 static void iscsit_handle_nopin_timeout(unsigned long data)
1029 {
1030         struct iscsi_conn *conn = (struct iscsi_conn *) data;
1031
1032         iscsit_inc_conn_usage_count(conn);
1033
1034         spin_lock_bh(&conn->nopin_timer_lock);
1035         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1036                 spin_unlock_bh(&conn->nopin_timer_lock);
1037                 iscsit_dec_conn_usage_count(conn);
1038                 return;
1039         }
1040         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1041         spin_unlock_bh(&conn->nopin_timer_lock);
1042
1043         iscsit_add_nopin(conn, 1);
1044         iscsit_dec_conn_usage_count(conn);
1045 }
1046
1047 /*
1048  * Called with conn->nopin_timer_lock held.
1049  */
1050 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1051 {
1052         struct iscsi_session *sess = conn->sess;
1053         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1054         /*
1055         * NOPIN timeout is disabled.
1056          */
1057         if (!na->nopin_timeout)
1058                 return;
1059
1060         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1061                 return;
1062
1063         init_timer(&conn->nopin_timer);
1064         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1065         conn->nopin_timer.data = (unsigned long)conn;
1066         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1067         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1068         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1069         add_timer(&conn->nopin_timer);
1070
1071         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1072                 " interval\n", conn->cid, na->nopin_timeout);
1073 }
1074
1075 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1076 {
1077         struct iscsi_session *sess = conn->sess;
1078         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1079         /*
1080          * NOPIN timeout is disabled..
1081          */
1082         if (!na->nopin_timeout)
1083                 return;
1084
1085         spin_lock_bh(&conn->nopin_timer_lock);
1086         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1087                 spin_unlock_bh(&conn->nopin_timer_lock);
1088                 return;
1089         }
1090
1091         init_timer(&conn->nopin_timer);
1092         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1093         conn->nopin_timer.data = (unsigned long)conn;
1094         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1095         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1096         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1097         add_timer(&conn->nopin_timer);
1098
1099         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1100                         " interval\n", conn->cid, na->nopin_timeout);
1101         spin_unlock_bh(&conn->nopin_timer_lock);
1102 }
1103
1104 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1105 {
1106         spin_lock_bh(&conn->nopin_timer_lock);
1107         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1108                 spin_unlock_bh(&conn->nopin_timer_lock);
1109                 return;
1110         }
1111         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1112         spin_unlock_bh(&conn->nopin_timer_lock);
1113
1114         del_timer_sync(&conn->nopin_timer);
1115
1116         spin_lock_bh(&conn->nopin_timer_lock);
1117         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1118         spin_unlock_bh(&conn->nopin_timer_lock);
1119 }
1120
1121 int iscsit_send_tx_data(
1122         struct iscsi_cmd *cmd,
1123         struct iscsi_conn *conn,
1124         int use_misc)
1125 {
1126         int tx_sent, tx_size;
1127         u32 iov_count;
1128         struct kvec *iov;
1129
1130 send_data:
1131         tx_size = cmd->tx_size;
1132
1133         if (!use_misc) {
1134                 iov = &cmd->iov_data[0];
1135                 iov_count = cmd->iov_data_count;
1136         } else {
1137                 iov = &cmd->iov_misc[0];
1138                 iov_count = cmd->iov_misc_count;
1139         }
1140
1141         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1142         if (tx_size != tx_sent) {
1143                 if (tx_sent == -EAGAIN) {
1144                         pr_err("tx_data() returned -EAGAIN\n");
1145                         goto send_data;
1146                 } else
1147                         return -1;
1148         }
1149         cmd->tx_size = 0;
1150
1151         return 0;
1152 }
1153
1154 int iscsit_fe_sendpage_sg(
1155         struct iscsi_cmd *cmd,
1156         struct iscsi_conn *conn)
1157 {
1158         struct scatterlist *sg = cmd->first_data_sg;
1159         struct kvec iov;
1160         u32 tx_hdr_size, data_len;
1161         u32 offset = cmd->first_data_sg_off;
1162         int tx_sent, iov_off;
1163
1164 send_hdr:
1165         tx_hdr_size = ISCSI_HDR_LEN;
1166         if (conn->conn_ops->HeaderDigest)
1167                 tx_hdr_size += ISCSI_CRC_LEN;
1168
1169         iov.iov_base = cmd->pdu;
1170         iov.iov_len = tx_hdr_size;
1171
1172         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1173         if (tx_hdr_size != tx_sent) {
1174                 if (tx_sent == -EAGAIN) {
1175                         pr_err("tx_data() returned -EAGAIN\n");
1176                         goto send_hdr;
1177                 }
1178                 return -1;
1179         }
1180
1181         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1182         /*
1183          * Set iov_off used by padding and data digest tx_data() calls below
1184          * in order to determine proper offset into cmd->iov_data[]
1185          */
1186         if (conn->conn_ops->DataDigest) {
1187                 data_len -= ISCSI_CRC_LEN;
1188                 if (cmd->padding)
1189                         iov_off = (cmd->iov_data_count - 2);
1190                 else
1191                         iov_off = (cmd->iov_data_count - 1);
1192         } else {
1193                 iov_off = (cmd->iov_data_count - 1);
1194         }
1195         /*
1196          * Perform sendpage() for each page in the scatterlist
1197          */
1198         while (data_len) {
1199                 u32 space = (sg->length - offset);
1200                 u32 sub_len = min_t(u32, data_len, space);
1201 send_pg:
1202                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1203                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1204                 if (tx_sent != sub_len) {
1205                         if (tx_sent == -EAGAIN) {
1206                                 pr_err("tcp_sendpage() returned"
1207                                                 " -EAGAIN\n");
1208                                 goto send_pg;
1209                         }
1210
1211                         pr_err("tcp_sendpage() failure: %d\n",
1212                                         tx_sent);
1213                         return -1;
1214                 }
1215
1216                 data_len -= sub_len;
1217                 offset = 0;
1218                 sg = sg_next(sg);
1219         }
1220
1221 send_padding:
1222         if (cmd->padding) {
1223                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1224
1225                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1226                 if (cmd->padding != tx_sent) {
1227                         if (tx_sent == -EAGAIN) {
1228                                 pr_err("tx_data() returned -EAGAIN\n");
1229                                 goto send_padding;
1230                         }
1231                         return -1;
1232                 }
1233         }
1234
1235 send_datacrc:
1236         if (conn->conn_ops->DataDigest) {
1237                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1238
1239                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1240                 if (ISCSI_CRC_LEN != tx_sent) {
1241                         if (tx_sent == -EAGAIN) {
1242                                 pr_err("tx_data() returned -EAGAIN\n");
1243                                 goto send_datacrc;
1244                         }
1245                         return -1;
1246                 }
1247         }
1248
1249         return 0;
1250 }
1251
1252 /*
1253  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1254  *      back to the Initiator when an expection condition occurs with the
1255  *      errors set in status_class and status_detail.
1256  *
1257  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1258  *      Returns:        0 on success, -1 on error.
1259  */
1260 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1261 {
1262         u8 iscsi_hdr[ISCSI_HDR_LEN];
1263         int err;
1264         struct kvec iov;
1265         struct iscsi_login_rsp *hdr;
1266
1267         iscsit_collect_login_stats(conn, status_class, status_detail);
1268
1269         memset(&iov, 0, sizeof(struct kvec));
1270         memset(&iscsi_hdr, 0x0, ISCSI_HDR_LEN);
1271
1272         hdr     = (struct iscsi_login_rsp *)&iscsi_hdr;
1273         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1274         hdr->status_class       = status_class;
1275         hdr->status_detail      = status_detail;
1276         hdr->itt                = cpu_to_be32(conn->login_itt);
1277
1278         iov.iov_base            = &iscsi_hdr;
1279         iov.iov_len             = ISCSI_HDR_LEN;
1280
1281         PRINT_BUFF(iscsi_hdr, ISCSI_HDR_LEN);
1282
1283         err = tx_data(conn, &iov, 1, ISCSI_HDR_LEN);
1284         if (err != ISCSI_HDR_LEN) {
1285                 pr_err("tx_data returned less than expected\n");
1286                 return -1;
1287         }
1288
1289         return 0;
1290 }
1291
1292 void iscsit_print_session_params(struct iscsi_session *sess)
1293 {
1294         struct iscsi_conn *conn;
1295
1296         pr_debug("-----------------------------[Session Params for"
1297                 " SID: %u]-----------------------------\n", sess->sid);
1298         spin_lock_bh(&sess->conn_lock);
1299         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1300                 iscsi_dump_conn_ops(conn->conn_ops);
1301         spin_unlock_bh(&sess->conn_lock);
1302
1303         iscsi_dump_sess_ops(sess->sess_ops);
1304 }
1305
1306 static int iscsit_do_rx_data(
1307         struct iscsi_conn *conn,
1308         struct iscsi_data_count *count)
1309 {
1310         int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
1311         struct kvec *iov_p;
1312         struct msghdr msg;
1313
1314         if (!conn || !conn->sock || !conn->conn_ops)
1315                 return -1;
1316
1317         memset(&msg, 0, sizeof(struct msghdr));
1318
1319         iov_p = count->iov;
1320         iov_len = count->iov_count;
1321
1322         while (total_rx < data) {
1323                 rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
1324                                         (data - total_rx), MSG_WAITALL);
1325                 if (rx_loop <= 0) {
1326                         pr_debug("rx_loop: %d total_rx: %d\n",
1327                                 rx_loop, total_rx);
1328                         return rx_loop;
1329                 }
1330                 total_rx += rx_loop;
1331                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1332                                 rx_loop, total_rx, data);
1333         }
1334
1335         return total_rx;
1336 }
1337
1338 static int iscsit_do_tx_data(
1339         struct iscsi_conn *conn,
1340         struct iscsi_data_count *count)
1341 {
1342         int data = count->data_length, total_tx = 0, tx_loop = 0, iov_len;
1343         struct kvec *iov_p;
1344         struct msghdr msg;
1345
1346         if (!conn || !conn->sock || !conn->conn_ops)
1347                 return -1;
1348
1349         if (data <= 0) {
1350                 pr_err("Data length is: %d\n", data);
1351                 return -1;
1352         }
1353
1354         memset(&msg, 0, sizeof(struct msghdr));
1355
1356         iov_p = count->iov;
1357         iov_len = count->iov_count;
1358
1359         while (total_tx < data) {
1360                 tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1361                                         (data - total_tx));
1362                 if (tx_loop <= 0) {
1363                         pr_debug("tx_loop: %d total_tx %d\n",
1364                                 tx_loop, total_tx);
1365                         return tx_loop;
1366                 }
1367                 total_tx += tx_loop;
1368                 pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1369                                         tx_loop, total_tx, data);
1370         }
1371
1372         return total_tx;
1373 }
1374
1375 int rx_data(
1376         struct iscsi_conn *conn,
1377         struct kvec *iov,
1378         int iov_count,
1379         int data)
1380 {
1381         struct iscsi_data_count c;
1382
1383         if (!conn || !conn->sock || !conn->conn_ops)
1384                 return -1;
1385
1386         memset(&c, 0, sizeof(struct iscsi_data_count));
1387         c.iov = iov;
1388         c.iov_count = iov_count;
1389         c.data_length = data;
1390         c.type = ISCSI_RX_DATA;
1391
1392         return iscsit_do_rx_data(conn, &c);
1393 }
1394
1395 int tx_data(
1396         struct iscsi_conn *conn,
1397         struct kvec *iov,
1398         int iov_count,
1399         int data)
1400 {
1401         struct iscsi_data_count c;
1402
1403         if (!conn || !conn->sock || !conn->conn_ops)
1404                 return -1;
1405
1406         memset(&c, 0, sizeof(struct iscsi_data_count));
1407         c.iov = iov;
1408         c.iov_count = iov_count;
1409         c.data_length = data;
1410         c.type = ISCSI_TX_DATA;
1411
1412         return iscsit_do_tx_data(conn, &c);
1413 }
1414
1415 void iscsit_collect_login_stats(
1416         struct iscsi_conn *conn,
1417         u8 status_class,
1418         u8 status_detail)
1419 {
1420         struct iscsi_param *intrname = NULL;
1421         struct iscsi_tiqn *tiqn;
1422         struct iscsi_login_stats *ls;
1423
1424         tiqn = iscsit_snmp_get_tiqn(conn);
1425         if (!tiqn)
1426                 return;
1427
1428         ls = &tiqn->login_stats;
1429
1430         spin_lock(&ls->lock);
1431         if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1432             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1433                 /* We already have the failure info for this login */
1434                 spin_unlock(&ls->lock);
1435                 return;
1436         }
1437
1438         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1439                 ls->accepts++;
1440         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1441                 ls->redirects++;
1442                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1443         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1444                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1445                 ls->authenticate_fails++;
1446                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1447         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1448                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1449                 ls->authorize_fails++;
1450                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1451         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1452                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1453                 ls->negotiate_fails++;
1454                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1455         } else {
1456                 ls->other_fails++;
1457                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1458         }
1459
1460         /* Save initiator name, ip address and time, if it is a failed login */
1461         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1462                 if (conn->param_list)
1463                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1464                                                              conn->param_list);
1465                 strcpy(ls->last_intr_fail_name,
1466                        (intrname ? intrname->value : "Unknown"));
1467
1468                 ls->last_intr_fail_ip_family = conn->sock->sk->sk_family;
1469                 snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1470                                 "%s", conn->login_ip);
1471                 ls->last_fail_time = get_jiffies_64();
1472         }
1473
1474         spin_unlock(&ls->lock);
1475 }
1476
1477 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1478 {
1479         struct iscsi_portal_group *tpg;
1480
1481         if (!conn || !conn->sess)
1482                 return NULL;
1483
1484         tpg = conn->sess->tpg;
1485         if (!tpg)
1486                 return NULL;
1487
1488         if (!tpg->tpg_tiqn)
1489                 return NULL;
1490
1491         return tpg->tpg_tiqn;
1492 }