drivers/target/iscsi/iscsi_target_util.c

   1 /*******************************************************************************
   2  * This file contains the iSCSI Target specific utility functions.
   3  *
   4  * (c) Copyright 2007-2013 Datera, Inc.
   5  *
   6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  ******************************************************************************/
  18
  19 #include <linux/list.h>
  20 #include <linux/percpu_ida.h>
  21 #include <scsi/scsi_tcq.h>
  22 #include <scsi/iscsi_proto.h>
  23 #include <target/target_core_base.h>
  24 #include <target/target_core_fabric.h>
  25 #include <target/target_core_configfs.h>
  26 #include <target/iscsi/iscsi_transport.h>
  27
  28 #include "iscsi_target_core.h"
  29 #include "iscsi_target_parameters.h"
  30 #include "iscsi_target_seq_pdu_list.h"
  31 #include "iscsi_target_datain_values.h"
  32 #include "iscsi_target_erl0.h"
  33 #include "iscsi_target_erl1.h"
  34 #include "iscsi_target_erl2.h"
  35 #include "iscsi_target_tpg.h"
  36 #include "iscsi_target_tq.h"
  37 #include "iscsi_target_util.h"
  38 #include "iscsi_target.h"
  39
  40 #define PRINT_BUFF(buff, len)                                   \
  41 {                                                               \
  42         int zzz;                                                \
  43                                                                 \
  44         pr_debug("%d:\n", __LINE__);                            \
  45         for (zzz = 0; zzz < len; zzz++) {                       \
  46                 if (zzz % 16 == 0) {                            \
  47                         if (zzz)                                \
  48                                 pr_debug("\n");                 \
  49                         pr_debug("%4i: ", zzz);                 \
  50                 }                                               \
  51                 pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  52         }                                                       \
  53         if ((len + 1) % 16)                                     \
  54                 pr_debug("\n");                                 \
  55 }
  56
  57 extern struct list_head g_tiqn_list;
  58 extern spinlock_t tiqn_lock;
  59
  60 /*
  61  *      Called with cmd->r2t_lock held.
  62  */
  63 int iscsit_add_r2t_to_list(
  64         struct iscsi_cmd *cmd,
  65         u32 offset,
  66         u32 xfer_len,
  67         int recovery,
  68         u32 r2t_sn)
  69 {
  70         struct iscsi_r2t *r2t;
  71
  72         r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  73         if (!r2t) {
  74                 pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  75                 return -1;
  76         }
  77         INIT_LIST_HEAD(&r2t->r2t_list);
  78
  79         r2t->recovery_r2t = recovery;
  80         r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  81         r2t->offset = offset;
  82         r2t->xfer_len = xfer_len;
  83         list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  84         spin_unlock_bh(&cmd->r2t_lock);
  85
  86         iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  87
  88         spin_lock_bh(&cmd->r2t_lock);
  89         return 0;
  90 }
  91
  92 struct iscsi_r2t *iscsit_get_r2t_for_eos(
  93         struct iscsi_cmd *cmd,
  94         u32 offset,
  95         u32 length)
  96 {
  97         struct iscsi_r2t *r2t;
  98
  99         spin_lock_bh(&cmd->r2t_lock);
 100         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 101                 if ((r2t->offset <= offset) &&
 102                     (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 103                         spin_unlock_bh(&cmd->r2t_lock);
 104                         return r2t;
 105                 }
 106         }
 107         spin_unlock_bh(&cmd->r2t_lock);
 108
 109         pr_err("Unable to locate R2T for Offset: %u, Length:"
 110                         " %u\n", offset, length);
 111         return NULL;
 112 }
 113
 114 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 115 {
 116         struct iscsi_r2t *r2t;
 117
 118         spin_lock_bh(&cmd->r2t_lock);
 119         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 120                 if (!r2t->sent_r2t) {
 121                         spin_unlock_bh(&cmd->r2t_lock);
 122                         return r2t;
 123                 }
 124         }
 125         spin_unlock_bh(&cmd->r2t_lock);
 126
 127         pr_err("Unable to locate next R2T to send for ITT:"
 128                         " 0x%08x.\n", cmd->init_task_tag);
 129         return NULL;
 130 }
 131
 132 /*
 133  *      Called with cmd->r2t_lock held.
 134  */
 135 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 136 {
 137         list_del(&r2t->r2t_list);
 138         kmem_cache_free(lio_r2t_cache, r2t);
 139 }
 140
 141 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 142 {
 143         struct iscsi_r2t *r2t, *r2t_tmp;
 144
 145         spin_lock_bh(&cmd->r2t_lock);
 146         list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 147                 iscsit_free_r2t(r2t, cmd);
 148         spin_unlock_bh(&cmd->r2t_lock);
 149 }
 150
 151 /*
 152  * May be called from software interrupt (timer) context for allocating
 153  * iSCSI NopINs.
 154  */
 155 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, gfp_t gfp_mask)
 156 {
 157         struct iscsi_cmd *cmd;
 158         struct se_session *se_sess = conn->sess->se_sess;
 159         int size, tag;
 160
 161         tag = percpu_ida_alloc(&se_sess->sess_tag_pool, gfp_mask);
 162         size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
 163         cmd = (struct iscsi_cmd *)(se_sess->sess_cmd_map + (tag * size));
 164         memset(cmd, 0, size);
 165
 166         cmd->se_cmd.map_tag = tag;
 167         cmd->conn = conn;
 168         INIT_LIST_HEAD(&cmd->i_conn_node);
 169         INIT_LIST_HEAD(&cmd->datain_list);
 170         INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 171         spin_lock_init(&cmd->datain_lock);
 172         spin_lock_init(&cmd->dataout_timeout_lock);
 173         spin_lock_init(&cmd->istate_lock);
 174         spin_lock_init(&cmd->error_lock);
 175         spin_lock_init(&cmd->r2t_lock);
 176
 177         return cmd;
 178 }
 179 EXPORT_SYMBOL(iscsit_allocate_cmd);
 180
 181 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 182         struct iscsi_cmd *cmd,
 183         u32 seq_send_order)
 184 {
 185         u32 i;
 186
 187         for (i = 0; i < cmd->seq_count; i++)
 188                 if (cmd->seq_list[i].seq_send_order == seq_send_order)
 189                         return &cmd->seq_list[i];
 190
 191         return NULL;
 192 }
 193
 194 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 195 {
 196         u32 i;
 197
 198         if (!cmd->seq_list) {
 199                 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 200                 return NULL;
 201         }
 202
 203         for (i = 0; i < cmd->seq_count; i++) {
 204                 if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 205                         continue;
 206                 if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 207                         cmd->seq_send_order++;
 208                         return &cmd->seq_list[i];
 209                 }
 210         }
 211
 212         return NULL;
 213 }
 214
 215 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 216         struct iscsi_cmd *cmd,
 217         u32 r2t_sn)
 218 {
 219         struct iscsi_r2t *r2t;
 220
 221         spin_lock_bh(&cmd->r2t_lock);
 222         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 223                 if (r2t->r2t_sn == r2t_sn) {
 224                         spin_unlock_bh(&cmd->r2t_lock);
 225                         return r2t;
 226                 }
 227         }
 228         spin_unlock_bh(&cmd->r2t_lock);
 229
 230         return NULL;
 231 }
 232
 233 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 234 {
 235         int ret;
 236
 237         /*
 238          * This is the proper method of checking received CmdSN against
 239          * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 240          * or order CmdSNs due to multiple connection sessions and/or
 241          * CRC failures.
 242          */
 243         if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) {
 244                 pr_err("Received CmdSN: 0x%08x is greater than"
 245                        " MaxCmdSN: 0x%08x, protocol error.\n", cmdsn,
 246                        sess->max_cmd_sn);
 247                 ret = CMDSN_ERROR_CANNOT_RECOVER;
 248
 249         } else if (cmdsn == sess->exp_cmd_sn) {
 250                 sess->exp_cmd_sn++;
 251                 pr_debug("Received CmdSN matches ExpCmdSN,"
 252                       " incremented ExpCmdSN to: 0x%08x\n",
 253                       sess->exp_cmd_sn);
 254                 ret = CMDSN_NORMAL_OPERATION;
 255
 256         } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 257                 pr_debug("Received CmdSN: 0x%08x is greater"
 258                       " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 259                       cmdsn, sess->exp_cmd_sn);
 260                 ret = CMDSN_HIGHER_THAN_EXP;
 261
 262         } else {
 263                 pr_err("Received CmdSN: 0x%08x is less than"
 264                        " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 265                        sess->exp_cmd_sn);
 266                 ret = CMDSN_LOWER_THAN_EXP;
 267         }
 268
 269         return ret;
 270 }
 271
 272 /*
 273  * Commands may be received out of order if MC/S is in use.
 274  * Ensure they are executed in CmdSN order.
 275  */
 276 int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 277                         unsigned char *buf, __be32 cmdsn)
 278 {
 279         int ret, cmdsn_ret;
 280         bool reject = false;
 281         u8 reason = ISCSI_REASON_BOOKMARK_NO_RESOURCES;
 282
 283         mutex_lock(&conn->sess->cmdsn_mutex);
 284
 285         cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
 286         switch (cmdsn_ret) {
 287         case CMDSN_NORMAL_OPERATION:
 288                 ret = iscsit_execute_cmd(cmd, 0);
 289                 if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 290                         iscsit_execute_ooo_cmdsns(conn->sess);
 291                 else if (ret < 0) {
 292                         reject = true;
 293                         ret = CMDSN_ERROR_CANNOT_RECOVER;
 294                 }
 295                 break;
 296         case CMDSN_HIGHER_THAN_EXP:
 297                 ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
 298                 if (ret < 0) {
 299                         reject = true;
 300                         ret = CMDSN_ERROR_CANNOT_RECOVER;
 301                         break;
 302                 }
 303                 ret = CMDSN_HIGHER_THAN_EXP;
 304                 break;
 305         case CMDSN_LOWER_THAN_EXP:
 306                 cmd->i_state = ISTATE_REMOVE;
 307                 iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 308                 ret = cmdsn_ret;
 309                 break;
 310         default:
 311                 reason = ISCSI_REASON_PROTOCOL_ERROR;
 312                 reject = true;
 313                 ret = cmdsn_ret;
 314                 break;
 315         }
 316         mutex_unlock(&conn->sess->cmdsn_mutex);
 317
 318         if (reject)
 319                 iscsit_reject_cmd(cmd, reason, buf);
 320
 321         return ret;
 322 }
 323 EXPORT_SYMBOL(iscsit_sequence_cmd);
 324
 325 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 326 {
 327         struct iscsi_conn *conn = cmd->conn;
 328         struct se_cmd *se_cmd = &cmd->se_cmd;
 329         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 330         u32 payload_length = ntoh24(hdr->dlength);
 331
 332         if (conn->sess->sess_ops->InitialR2T) {
 333                 pr_err("Received unexpected unsolicited data"
 334                         " while InitialR2T=Yes, protocol error.\n");
 335                 transport_send_check_condition_and_sense(se_cmd,
 336                                 TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 337                 return -1;
 338         }
 339
 340         if ((cmd->first_burst_len + payload_length) >
 341              conn->sess->sess_ops->FirstBurstLength) {
 342                 pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 343                         " for this Unsolicited DataOut Burst.\n",
 344                         (cmd->first_burst_len + payload_length),
 345                                 conn->sess->sess_ops->FirstBurstLength);
 346                 transport_send_check_condition_and_sense(se_cmd,
 347                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 348                 return -1;
 349         }
 350
 351         if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 352                 return 0;
 353
 354         if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 355             ((cmd->first_burst_len + payload_length) !=
 356               conn->sess->sess_ops->FirstBurstLength)) {
 357                 pr_err("Unsolicited non-immediate data received %u"
 358                         " does not equal FirstBurstLength: %u, and does"
 359                         " not equal ExpXferLen %u.\n",
 360                         (cmd->first_burst_len + payload_length),
 361                         conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 362                 transport_send_check_condition_and_sense(se_cmd,
 363                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 364                 return -1;
 365         }
 366         return 0;
 367 }
 368
 369 struct iscsi_cmd *iscsit_find_cmd_from_itt(
 370         struct iscsi_conn *conn,
 371         itt_t init_task_tag)
 372 {
 373         struct iscsi_cmd *cmd;
 374
 375         spin_lock_bh(&conn->cmd_lock);
 376         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 377                 if (cmd->init_task_tag == init_task_tag) {
 378                         spin_unlock_bh(&conn->cmd_lock);
 379                         return cmd;
 380                 }
 381         }
 382         spin_unlock_bh(&conn->cmd_lock);
 383
 384         pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 385                         init_task_tag, conn->cid);
 386         return NULL;
 387 }
 388
 389 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 390         struct iscsi_conn *conn,
 391         itt_t init_task_tag,
 392         u32 length)
 393 {
 394         struct iscsi_cmd *cmd;
 395
 396         spin_lock_bh(&conn->cmd_lock);
 397         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 398                 if (cmd->init_task_tag == init_task_tag) {
 399                         spin_unlock_bh(&conn->cmd_lock);
 400                         return cmd;
 401                 }
 402         }
 403         spin_unlock_bh(&conn->cmd_lock);
 404
 405         pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 406                         " dumping payload\n", init_task_tag, conn->cid);
 407         if (length)
 408                 iscsit_dump_data_payload(conn, length, 1);
 409
 410         return NULL;
 411 }
 412
 413 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 414         struct iscsi_conn *conn,
 415         u32 targ_xfer_tag)
 416 {
 417         struct iscsi_cmd *cmd = NULL;
 418
 419         spin_lock_bh(&conn->cmd_lock);
 420         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 421                 if (cmd->targ_xfer_tag == targ_xfer_tag) {
 422                         spin_unlock_bh(&conn->cmd_lock);
 423                         return cmd;
 424                 }
 425         }
 426         spin_unlock_bh(&conn->cmd_lock);
 427
 428         pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 429                         targ_xfer_tag, conn->cid);
 430         return NULL;
 431 }
 432
 433 int iscsit_find_cmd_for_recovery(
 434         struct iscsi_session *sess,
 435         struct iscsi_cmd **cmd_ptr,
 436         struct iscsi_conn_recovery **cr_ptr,
 437         itt_t init_task_tag)
 438 {
 439         struct iscsi_cmd *cmd = NULL;
 440         struct iscsi_conn_recovery *cr;
 441         /*
 442          * Scan through the inactive connection recovery list's command list.
 443          * If init_task_tag matches the command is still alligent.
 444          */
 445         spin_lock(&sess->cr_i_lock);
 446         list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 447                 spin_lock(&cr->conn_recovery_cmd_lock);
 448                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 449                         if (cmd->init_task_tag == init_task_tag) {
 450                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 451                                 spin_unlock(&sess->cr_i_lock);
 452
 453                                 *cr_ptr = cr;
 454                                 *cmd_ptr = cmd;
 455                                 return -2;
 456                         }
 457                 }
 458                 spin_unlock(&cr->conn_recovery_cmd_lock);
 459         }
 460         spin_unlock(&sess->cr_i_lock);
 461         /*
 462          * Scan through the active connection recovery list's command list.
 463          * If init_task_tag matches the command is ready to be reassigned.
 464          */
 465         spin_lock(&sess->cr_a_lock);
 466         list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 467                 spin_lock(&cr->conn_recovery_cmd_lock);
 468                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 469                         if (cmd->init_task_tag == init_task_tag) {
 470                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 471                                 spin_unlock(&sess->cr_a_lock);
 472
 473                                 *cr_ptr = cr;
 474                                 *cmd_ptr = cmd;
 475                                 return 0;
 476                         }
 477                 }
 478                 spin_unlock(&cr->conn_recovery_cmd_lock);
 479         }
 480         spin_unlock(&sess->cr_a_lock);
 481
 482         return -1;
 483 }
 484
 485 void iscsit_add_cmd_to_immediate_queue(
 486         struct iscsi_cmd *cmd,
 487         struct iscsi_conn *conn,
 488         u8 state)
 489 {
 490         struct iscsi_queue_req *qr;
 491
 492         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 493         if (!qr) {
 494                 pr_err("Unable to allocate memory for"
 495                                 " struct iscsi_queue_req\n");
 496                 return;
 497         }
 498         INIT_LIST_HEAD(&qr->qr_list);
 499         qr->cmd = cmd;
 500         qr->state = state;
 501
 502         spin_lock_bh(&conn->immed_queue_lock);
 503         list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 504         atomic_inc(&cmd->immed_queue_count);
 505         atomic_set(&conn->check_immediate_queue, 1);
 506         spin_unlock_bh(&conn->immed_queue_lock);
 507
 508         wake_up(&conn->queues_wq);
 509 }
 510
 511 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 512 {
 513         struct iscsi_queue_req *qr;
 514
 515         spin_lock_bh(&conn->immed_queue_lock);
 516         if (list_empty(&conn->immed_queue_list)) {
 517                 spin_unlock_bh(&conn->immed_queue_lock);
 518                 return NULL;
 519         }
 520         qr = list_first_entry(&conn->immed_queue_list,
 521                               struct iscsi_queue_req, qr_list);
 522
 523         list_del(&qr->qr_list);
 524         if (qr->cmd)
 525                 atomic_dec(&qr->cmd->immed_queue_count);
 526         spin_unlock_bh(&conn->immed_queue_lock);
 527
 528         return qr;
 529 }
 530
 531 static void iscsit_remove_cmd_from_immediate_queue(
 532         struct iscsi_cmd *cmd,
 533         struct iscsi_conn *conn)
 534 {
 535         struct iscsi_queue_req *qr, *qr_tmp;
 536
 537         spin_lock_bh(&conn->immed_queue_lock);
 538         if (!atomic_read(&cmd->immed_queue_count)) {
 539                 spin_unlock_bh(&conn->immed_queue_lock);
 540                 return;
 541         }
 542
 543         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 544                 if (qr->cmd != cmd)
 545                         continue;
 546
 547                 atomic_dec(&qr->cmd->immed_queue_count);
 548                 list_del(&qr->qr_list);
 549                 kmem_cache_free(lio_qr_cache, qr);
 550         }
 551         spin_unlock_bh(&conn->immed_queue_lock);
 552
 553         if (atomic_read(&cmd->immed_queue_count)) {
 554                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 555                         cmd->init_task_tag,
 556                         atomic_read(&cmd->immed_queue_count));
 557         }
 558 }
 559
 560 void iscsit_add_cmd_to_response_queue(
 561         struct iscsi_cmd *cmd,
 562         struct iscsi_conn *conn,
 563         u8 state)
 564 {
 565         struct iscsi_queue_req *qr;
 566
 567         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 568         if (!qr) {
 569                 pr_err("Unable to allocate memory for"
 570                         " struct iscsi_queue_req\n");
 571                 return;
 572         }
 573         INIT_LIST_HEAD(&qr->qr_list);
 574         qr->cmd = cmd;
 575         qr->state = state;
 576
 577         spin_lock_bh(&conn->response_queue_lock);
 578         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 579         atomic_inc(&cmd->response_queue_count);
 580         spin_unlock_bh(&conn->response_queue_lock);
 581
 582         wake_up(&conn->queues_wq);
 583 }
 584
 585 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 586 {
 587         struct iscsi_queue_req *qr;
 588
 589         spin_lock_bh(&conn->response_queue_lock);
 590         if (list_empty(&conn->response_queue_list)) {
 591                 spin_unlock_bh(&conn->response_queue_lock);
 592                 return NULL;
 593         }
 594
 595         qr = list_first_entry(&conn->response_queue_list,
 596                               struct iscsi_queue_req, qr_list);
 597
 598         list_del(&qr->qr_list);
 599         if (qr->cmd)
 600                 atomic_dec(&qr->cmd->response_queue_count);
 601         spin_unlock_bh(&conn->response_queue_lock);
 602
 603         return qr;
 604 }
 605
 606 static void iscsit_remove_cmd_from_response_queue(
 607         struct iscsi_cmd *cmd,
 608         struct iscsi_conn *conn)
 609 {
 610         struct iscsi_queue_req *qr, *qr_tmp;
 611
 612         spin_lock_bh(&conn->response_queue_lock);
 613         if (!atomic_read(&cmd->response_queue_count)) {
 614                 spin_unlock_bh(&conn->response_queue_lock);
 615                 return;
 616         }
 617
 618         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 619                                 qr_list) {
 620                 if (qr->cmd != cmd)
 621                         continue;
 622
 623                 atomic_dec(&qr->cmd->response_queue_count);
 624                 list_del(&qr->qr_list);
 625                 kmem_cache_free(lio_qr_cache, qr);
 626         }
 627         spin_unlock_bh(&conn->response_queue_lock);
 628
 629         if (atomic_read(&cmd->response_queue_count)) {
 630                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 631                         cmd->init_task_tag,
 632                         atomic_read(&cmd->response_queue_count));
 633         }
 634 }
 635
 636 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 637 {
 638         bool empty;
 639
 640         spin_lock_bh(&conn->immed_queue_lock);
 641         empty = list_empty(&conn->immed_queue_list);
 642         spin_unlock_bh(&conn->immed_queue_lock);
 643
 644         if (!empty)
 645                 return empty;
 646
 647         spin_lock_bh(&conn->response_queue_lock);
 648         empty = list_empty(&conn->response_queue_list);
 649         spin_unlock_bh(&conn->response_queue_lock);
 650
 651         return empty;
 652 }
 653
 654 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 655 {
 656         struct iscsi_queue_req *qr, *qr_tmp;
 657
 658         spin_lock_bh(&conn->immed_queue_lock);
 659         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 660                 list_del(&qr->qr_list);
 661                 if (qr->cmd)
 662                         atomic_dec(&qr->cmd->immed_queue_count);
 663
 664                 kmem_cache_free(lio_qr_cache, qr);
 665         }
 666         spin_unlock_bh(&conn->immed_queue_lock);
 667
 668         spin_lock_bh(&conn->response_queue_lock);
 669         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 670                         qr_list) {
 671                 list_del(&qr->qr_list);
 672                 if (qr->cmd)
 673                         atomic_dec(&qr->cmd->response_queue_count);
 674
 675                 kmem_cache_free(lio_qr_cache, qr);
 676         }
 677         spin_unlock_bh(&conn->response_queue_lock);
 678 }
 679
 680 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 681 {
 682         struct iscsi_session *sess;
 683         struct se_cmd *se_cmd = &cmd->se_cmd;
 684
 685         if (cmd->conn)
 686                 sess = cmd->conn->sess;
 687         else
 688                 sess = cmd->sess;
 689
 690         BUG_ON(!sess || !sess->se_sess);
 691
 692         kfree(cmd->buf_ptr);
 693         kfree(cmd->pdu_list);
 694         kfree(cmd->seq_list);
 695         kfree(cmd->tmr_req);
 696         kfree(cmd->iov_data);
 697         kfree(cmd->text_in_ptr);
 698
 699         percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 700 }
 701 EXPORT_SYMBOL(iscsit_release_cmd);
 702
 703 static void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool scsi_cmd,
 704                               bool check_queues)
 705 {
 706         struct iscsi_conn *conn = cmd->conn;
 707
 708         if (scsi_cmd) {
 709                 if (cmd->data_direction == DMA_TO_DEVICE) {
 710                         iscsit_stop_dataout_timer(cmd);
 711                         iscsit_free_r2ts_from_list(cmd);
 712                 }
 713                 if (cmd->data_direction == DMA_FROM_DEVICE)
 714                         iscsit_free_all_datain_reqs(cmd);
 715         }
 716
 717         if (conn && check_queues) {
 718                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 719                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 720         }
 721 }
 722
 723 void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 724 {
 725         struct se_cmd *se_cmd = NULL;
 726         int rc;
 727         /*
 728          * Determine if a struct se_cmd is associated with
 729          * this struct iscsi_cmd.
 730          */
 731         switch (cmd->iscsi_opcode) {
 732         case ISCSI_OP_SCSI_CMD:
 733                 se_cmd = &cmd->se_cmd;
 734                 __iscsit_free_cmd(cmd, true, shutdown);
 735                 /*
 736                  * Fallthrough
 737                  */
 738         case ISCSI_OP_SCSI_TMFUNC:
 739                 rc = transport_generic_free_cmd(&cmd->se_cmd, 1);
 740                 if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
 741                         __iscsit_free_cmd(cmd, true, shutdown);
 742                         target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 743                 }
 744                 break;
 745         case ISCSI_OP_REJECT:
 746                 /*
 747                  * Handle special case for REJECT when iscsi_add_reject*() has
 748                  * overwritten the original iscsi_opcode assignment, and the
 749                  * associated cmd->se_cmd needs to be released.
 750                  */
 751                 if (cmd->se_cmd.se_tfo != NULL) {
 752                         se_cmd = &cmd->se_cmd;
 753                         __iscsit_free_cmd(cmd, true, shutdown);
 754
 755                         rc = transport_generic_free_cmd(&cmd->se_cmd, 1);
 756                         if (!rc && shutdown && se_cmd->se_sess) {
 757                                 __iscsit_free_cmd(cmd, true, shutdown);
 758                                 target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 759                         }
 760                         break;
 761                 }
 762                 /* Fall-through */
 763         default:
 764                 __iscsit_free_cmd(cmd, false, shutdown);
 765                 iscsit_release_cmd(cmd);
 766                 break;
 767         }
 768 }
 769
 770 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 771 {
 772         spin_lock_bh(&sess->session_usage_lock);
 773         if (sess->session_usage_count != 0) {
 774                 sess->session_waiting_on_uc = 1;
 775                 spin_unlock_bh(&sess->session_usage_lock);
 776                 if (in_interrupt())
 777                         return 2;
 778
 779                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 780                 return 1;
 781         }
 782         spin_unlock_bh(&sess->session_usage_lock);
 783
 784         return 0;
 785 }
 786
 787 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 788 {
 789         spin_lock_bh(&sess->session_usage_lock);
 790         sess->session_usage_count--;
 791
 792         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 793                 complete(&sess->session_waiting_on_uc_comp);
 794
 795         spin_unlock_bh(&sess->session_usage_lock);
 796 }
 797
 798 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 799 {
 800         spin_lock_bh(&sess->session_usage_lock);
 801         sess->session_usage_count++;
 802         spin_unlock_bh(&sess->session_usage_lock);
 803 }
 804
 805 /*
 806  *      Setup conn->if_marker and conn->of_marker values based upon
 807  *      the initial marker-less interval. (see iSCSI v19 A.2)
 808  */
 809 int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 810 {
 811         int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 812         /*
 813          * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 814          */
 815         u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 816         u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 817
 818         if (conn->conn_ops->OFMarker) {
 819                 /*
 820                  * Account for the first Login Command received not
 821                  * via iscsi_recv_msg().
 822                  */
 823                 conn->of_marker += ISCSI_HDR_LEN;
 824                 if (conn->of_marker <= OFMarkInt) {
 825                         conn->of_marker = (OFMarkInt - conn->of_marker);
 826                 } else {
 827                         login_ofmarker_count = (conn->of_marker / OFMarkInt);
 828                         next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 829                                         (login_ofmarker_count * MARKER_SIZE);
 830                         conn->of_marker = (next_marker - conn->of_marker);
 831                 }
 832                 conn->of_marker_offset = 0;
 833                 pr_debug("Setting OFMarker value to %u based on Initial"
 834                         " Markerless Interval.\n", conn->of_marker);
 835         }
 836
 837         if (conn->conn_ops->IFMarker) {
 838                 if (conn->if_marker <= IFMarkInt) {
 839                         conn->if_marker = (IFMarkInt - conn->if_marker);
 840                 } else {
 841                         login_ifmarker_count = (conn->if_marker / IFMarkInt);
 842                         next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 843                                         (login_ifmarker_count * MARKER_SIZE);
 844                         conn->if_marker = (next_marker - conn->if_marker);
 845                 }
 846                 pr_debug("Setting IFMarker value to %u based on Initial"
 847                         " Markerless Interval.\n", conn->if_marker);
 848         }
 849
 850         return 0;
 851 }
 852
 853 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 854 {
 855         struct iscsi_conn *conn;
 856
 857         spin_lock_bh(&sess->conn_lock);
 858         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 859                 if ((conn->cid == cid) &&
 860                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 861                         iscsit_inc_conn_usage_count(conn);
 862                         spin_unlock_bh(&sess->conn_lock);
 863                         return conn;
 864                 }
 865         }
 866         spin_unlock_bh(&sess->conn_lock);
 867
 868         return NULL;
 869 }
 870
 871 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 872 {
 873         struct iscsi_conn *conn;
 874
 875         spin_lock_bh(&sess->conn_lock);
 876         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 877                 if (conn->cid == cid) {
 878                         iscsit_inc_conn_usage_count(conn);
 879                         spin_lock(&conn->state_lock);
 880                         atomic_set(&conn->connection_wait_rcfr, 1);
 881                         spin_unlock(&conn->state_lock);
 882                         spin_unlock_bh(&sess->conn_lock);
 883                         return conn;
 884                 }
 885         }
 886         spin_unlock_bh(&sess->conn_lock);
 887
 888         return NULL;
 889 }
 890
 891 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 892 {
 893         spin_lock_bh(&conn->conn_usage_lock);
 894         if (conn->conn_usage_count != 0) {
 895                 conn->conn_waiting_on_uc = 1;
 896                 spin_unlock_bh(&conn->conn_usage_lock);
 897
 898                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 899                 return;
 900         }
 901         spin_unlock_bh(&conn->conn_usage_lock);
 902 }
 903
 904 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 905 {
 906         spin_lock_bh(&conn->conn_usage_lock);
 907         conn->conn_usage_count--;
 908
 909         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 910                 complete(&conn->conn_waiting_on_uc_comp);
 911
 912         spin_unlock_bh(&conn->conn_usage_lock);
 913 }
 914
 915 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 916 {
 917         spin_lock_bh(&conn->conn_usage_lock);
 918         conn->conn_usage_count++;
 919         spin_unlock_bh(&conn->conn_usage_lock);
 920 }
 921
 922 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 923 {
 924         u8 state;
 925         struct iscsi_cmd *cmd;
 926
 927         cmd = iscsit_allocate_cmd(conn, GFP_ATOMIC);
 928         if (!cmd)
 929                 return -1;
 930
 931         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 932         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 933                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 934         cmd->init_task_tag = RESERVED_ITT;
 935         spin_lock_bh(&conn->sess->ttt_lock);
 936         cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
 937                         0xFFFFFFFF;
 938         if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
 939                 cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
 940         spin_unlock_bh(&conn->sess->ttt_lock);
 941
 942         spin_lock_bh(&conn->cmd_lock);
 943         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 944         spin_unlock_bh(&conn->cmd_lock);
 945
 946         if (want_response)
 947                 iscsit_start_nopin_response_timer(conn);
 948         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 949
 950         return 0;
 951 }
 952
 953 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 954 {
 955         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 956
 957         iscsit_inc_conn_usage_count(conn);
 958
 959         spin_lock_bh(&conn->nopin_timer_lock);
 960         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 961                 spin_unlock_bh(&conn->nopin_timer_lock);
 962                 iscsit_dec_conn_usage_count(conn);
 963                 return;
 964         }
 965
 966         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 967                 " SID: %u, failing connection.\n", conn->cid,
 968                         conn->sess->sid);
 969         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 970         spin_unlock_bh(&conn->nopin_timer_lock);
 971
 972         {
 973         struct iscsi_portal_group *tpg = conn->sess->tpg;
 974         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 975
 976         if (tiqn) {
 977                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 978                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 979                                 conn->sess->sess_ops->InitiatorName);
 980                 tiqn->sess_err_stats.last_sess_failure_type =
 981                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 982                 tiqn->sess_err_stats.cxn_timeout_errors++;
 983                 conn->sess->conn_timeout_errors++;
 984                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 985         }
 986         }
 987
 988         iscsit_cause_connection_reinstatement(conn, 0);
 989         iscsit_dec_conn_usage_count(conn);
 990 }
 991
 992 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 993 {
 994         struct iscsi_session *sess = conn->sess;
 995         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 996
 997         spin_lock_bh(&conn->nopin_timer_lock);
 998         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 999                 spin_unlock_bh(&conn->nopin_timer_lock);
1000                 return;
1001         }
1002
1003         mod_timer(&conn->nopin_response_timer,
1004                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
1005         spin_unlock_bh(&conn->nopin_timer_lock);
1006 }
1007
1008 /*
1009  *      Called with conn->nopin_timer_lock held.
1010  */
1011 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
1012 {
1013         struct iscsi_session *sess = conn->sess;
1014         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1015
1016         spin_lock_bh(&conn->nopin_timer_lock);
1017         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
1018                 spin_unlock_bh(&conn->nopin_timer_lock);
1019                 return;
1020         }
1021
1022         init_timer(&conn->nopin_response_timer);
1023         conn->nopin_response_timer.expires =
1024                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
1025         conn->nopin_response_timer.data = (unsigned long)conn;
1026         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
1027         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
1028         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
1029         add_timer(&conn->nopin_response_timer);
1030
1031         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
1032                 " seconds\n", conn->cid, na->nopin_response_timeout);
1033         spin_unlock_bh(&conn->nopin_timer_lock);
1034 }
1035
1036 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
1037 {
1038         spin_lock_bh(&conn->nopin_timer_lock);
1039         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1040                 spin_unlock_bh(&conn->nopin_timer_lock);
1041                 return;
1042         }
1043         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1044         spin_unlock_bh(&conn->nopin_timer_lock);
1045
1046         del_timer_sync(&conn->nopin_response_timer);
1047
1048         spin_lock_bh(&conn->nopin_timer_lock);
1049         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1050         spin_unlock_bh(&conn->nopin_timer_lock);
1051 }
1052
1053 static void iscsit_handle_nopin_timeout(unsigned long data)
1054 {
1055         struct iscsi_conn *conn = (struct iscsi_conn *) data;
1056
1057         iscsit_inc_conn_usage_count(conn);
1058
1059         spin_lock_bh(&conn->nopin_timer_lock);
1060         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1061                 spin_unlock_bh(&conn->nopin_timer_lock);
1062                 iscsit_dec_conn_usage_count(conn);
1063                 return;
1064         }
1065         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1066         spin_unlock_bh(&conn->nopin_timer_lock);
1067
1068         iscsit_add_nopin(conn, 1);
1069         iscsit_dec_conn_usage_count(conn);
1070 }
1071
1072 /*
1073  * Called with conn->nopin_timer_lock held.
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         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1086                 return;
1087
1088         init_timer(&conn->nopin_timer);
1089         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1090         conn->nopin_timer.data = (unsigned long)conn;
1091         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1092         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1093         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1094         add_timer(&conn->nopin_timer);
1095
1096         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1097                 " interval\n", conn->cid, na->nopin_timeout);
1098 }
1099
1100 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1101 {
1102         struct iscsi_session *sess = conn->sess;
1103         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1104         /*
1105          * NOPIN timeout is disabled..
1106          */
1107         if (!na->nopin_timeout)
1108                 return;
1109
1110         spin_lock_bh(&conn->nopin_timer_lock);
1111         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1112                 spin_unlock_bh(&conn->nopin_timer_lock);
1113                 return;
1114         }
1115
1116         init_timer(&conn->nopin_timer);
1117         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1118         conn->nopin_timer.data = (unsigned long)conn;
1119         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1120         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1121         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1122         add_timer(&conn->nopin_timer);
1123
1124         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1125                         " interval\n", conn->cid, na->nopin_timeout);
1126         spin_unlock_bh(&conn->nopin_timer_lock);
1127 }
1128
1129 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1130 {
1131         spin_lock_bh(&conn->nopin_timer_lock);
1132         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1133                 spin_unlock_bh(&conn->nopin_timer_lock);
1134                 return;
1135         }
1136         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1137         spin_unlock_bh(&conn->nopin_timer_lock);
1138
1139         del_timer_sync(&conn->nopin_timer);
1140
1141         spin_lock_bh(&conn->nopin_timer_lock);
1142         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1143         spin_unlock_bh(&conn->nopin_timer_lock);
1144 }
1145
1146 int iscsit_send_tx_data(
1147         struct iscsi_cmd *cmd,
1148         struct iscsi_conn *conn,
1149         int use_misc)
1150 {
1151         int tx_sent, tx_size;
1152         u32 iov_count;
1153         struct kvec *iov;
1154
1155 send_data:
1156         tx_size = cmd->tx_size;
1157
1158         if (!use_misc) {
1159                 iov = &cmd->iov_data[0];
1160                 iov_count = cmd->iov_data_count;
1161         } else {
1162                 iov = &cmd->iov_misc[0];
1163                 iov_count = cmd->iov_misc_count;
1164         }
1165
1166         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1167         if (tx_size != tx_sent) {
1168                 if (tx_sent == -EAGAIN) {
1169                         pr_err("tx_data() returned -EAGAIN\n");
1170                         goto send_data;
1171                 } else
1172                         return -1;
1173         }
1174         cmd->tx_size = 0;
1175
1176         return 0;
1177 }
1178
1179 int iscsit_fe_sendpage_sg(
1180         struct iscsi_cmd *cmd,
1181         struct iscsi_conn *conn)
1182 {
1183         struct scatterlist *sg = cmd->first_data_sg;
1184         struct kvec iov;
1185         u32 tx_hdr_size, data_len;
1186         u32 offset = cmd->first_data_sg_off;
1187         int tx_sent, iov_off;
1188
1189 send_hdr:
1190         tx_hdr_size = ISCSI_HDR_LEN;
1191         if (conn->conn_ops->HeaderDigest)
1192                 tx_hdr_size += ISCSI_CRC_LEN;
1193
1194         iov.iov_base = cmd->pdu;
1195         iov.iov_len = tx_hdr_size;
1196
1197         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1198         if (tx_hdr_size != tx_sent) {
1199                 if (tx_sent == -EAGAIN) {
1200                         pr_err("tx_data() returned -EAGAIN\n");
1201                         goto send_hdr;
1202                 }
1203                 return -1;
1204         }
1205
1206         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1207         /*
1208          * Set iov_off used by padding and data digest tx_data() calls below
1209          * in order to determine proper offset into cmd->iov_data[]
1210          */
1211         if (conn->conn_ops->DataDigest) {
1212                 data_len -= ISCSI_CRC_LEN;
1213                 if (cmd->padding)
1214                         iov_off = (cmd->iov_data_count - 2);
1215                 else
1216                         iov_off = (cmd->iov_data_count - 1);
1217         } else {
1218                 iov_off = (cmd->iov_data_count - 1);
1219         }
1220         /*
1221          * Perform sendpage() for each page in the scatterlist
1222          */
1223         while (data_len) {
1224                 u32 space = (sg->length - offset);
1225                 u32 sub_len = min_t(u32, data_len, space);
1226 send_pg:
1227                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1228                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1229                 if (tx_sent != sub_len) {
1230                         if (tx_sent == -EAGAIN) {
1231                                 pr_err("tcp_sendpage() returned"
1232                                                 " -EAGAIN\n");
1233                                 goto send_pg;
1234                         }
1235
1236                         pr_err("tcp_sendpage() failure: %d\n",
1237                                         tx_sent);
1238                         return -1;
1239                 }
1240
1241                 data_len -= sub_len;
1242                 offset = 0;
1243                 sg = sg_next(sg);
1244         }
1245
1246 send_padding:
1247         if (cmd->padding) {
1248                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1249
1250                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1251                 if (cmd->padding != tx_sent) {
1252                         if (tx_sent == -EAGAIN) {
1253                                 pr_err("tx_data() returned -EAGAIN\n");
1254                                 goto send_padding;
1255                         }
1256                         return -1;
1257                 }
1258         }
1259
1260 send_datacrc:
1261         if (conn->conn_ops->DataDigest) {
1262                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1263
1264                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1265                 if (ISCSI_CRC_LEN != tx_sent) {
1266                         if (tx_sent == -EAGAIN) {
1267                                 pr_err("tx_data() returned -EAGAIN\n");
1268                                 goto send_datacrc;
1269                         }
1270                         return -1;
1271                 }
1272         }
1273
1274         return 0;
1275 }
1276
1277 /*
1278  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1279  *      back to the Initiator when an expection condition occurs with the
1280  *      errors set in status_class and status_detail.
1281  *
1282  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1283  *      Returns:        0 on success, -1 on error.
1284  */
1285 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1286 {
1287         struct iscsi_login_rsp *hdr;
1288         struct iscsi_login *login = conn->conn_login;
1289
1290         login->login_failed = 1;
1291         iscsit_collect_login_stats(conn, status_class, status_detail);
1292
1293         hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1294         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1295         hdr->status_class       = status_class;
1296         hdr->status_detail      = status_detail;
1297         hdr->itt                = conn->login_itt;
1298
1299         return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1300 }
1301
1302 void iscsit_print_session_params(struct iscsi_session *sess)
1303 {
1304         struct iscsi_conn *conn;
1305
1306         pr_debug("-----------------------------[Session Params for"
1307                 " SID: %u]-----------------------------\n", sess->sid);
1308         spin_lock_bh(&sess->conn_lock);
1309         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1310                 iscsi_dump_conn_ops(conn->conn_ops);
1311         spin_unlock_bh(&sess->conn_lock);
1312
1313         iscsi_dump_sess_ops(sess->sess_ops);
1314 }
1315
1316 static int iscsit_do_rx_data(
1317         struct iscsi_conn *conn,
1318         struct iscsi_data_count *count)
1319 {
1320         int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
1321         struct kvec *iov_p;
1322         struct msghdr msg;
1323
1324         if (!conn || !conn->sock || !conn->conn_ops)
1325                 return -1;
1326
1327         memset(&msg, 0, sizeof(struct msghdr));
1328
1329         iov_p = count->iov;
1330         iov_len = count->iov_count;
1331
1332         while (total_rx < data) {
1333                 rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
1334                                         (data - total_rx), MSG_WAITALL);
1335                 if (rx_loop <= 0) {
1336                         pr_debug("rx_loop: %d total_rx: %d\n",
1337                                 rx_loop, total_rx);
1338                         return rx_loop;
1339                 }
1340                 total_rx += rx_loop;
1341                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1342                                 rx_loop, total_rx, data);
1343         }
1344
1345         return total_rx;
1346 }
1347
1348 static int iscsit_do_tx_data(
1349         struct iscsi_conn *conn,
1350         struct iscsi_data_count *count)
1351 {
1352         int data = count->data_length, total_tx = 0, tx_loop = 0, iov_len;
1353         struct kvec *iov_p;
1354         struct msghdr msg;
1355
1356         if (!conn || !conn->sock || !conn->conn_ops)
1357                 return -1;
1358
1359         if (data <= 0) {
1360                 pr_err("Data length is: %d\n", data);
1361                 return -1;
1362         }
1363
1364         memset(&msg, 0, sizeof(struct msghdr));
1365
1366         iov_p = count->iov;
1367         iov_len = count->iov_count;
1368
1369         while (total_tx < data) {
1370                 tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1371                                         (data - total_tx));
1372                 if (tx_loop <= 0) {
1373                         pr_debug("tx_loop: %d total_tx %d\n",
1374                                 tx_loop, total_tx);
1375                         return tx_loop;
1376                 }
1377                 total_tx += tx_loop;
1378                 pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1379                                         tx_loop, total_tx, data);
1380         }
1381
1382         return total_tx;
1383 }
1384
1385 int rx_data(
1386         struct iscsi_conn *conn,
1387         struct kvec *iov,
1388         int iov_count,
1389         int data)
1390 {
1391         struct iscsi_data_count c;
1392
1393         if (!conn || !conn->sock || !conn->conn_ops)
1394                 return -1;
1395
1396         memset(&c, 0, sizeof(struct iscsi_data_count));
1397         c.iov = iov;
1398         c.iov_count = iov_count;
1399         c.data_length = data;
1400         c.type = ISCSI_RX_DATA;
1401
1402         return iscsit_do_rx_data(conn, &c);
1403 }
1404
1405 int tx_data(
1406         struct iscsi_conn *conn,
1407         struct kvec *iov,
1408         int iov_count,
1409         int data)
1410 {
1411         struct iscsi_data_count c;
1412
1413         if (!conn || !conn->sock || !conn->conn_ops)
1414                 return -1;
1415
1416         memset(&c, 0, sizeof(struct iscsi_data_count));
1417         c.iov = iov;
1418         c.iov_count = iov_count;
1419         c.data_length = data;
1420         c.type = ISCSI_TX_DATA;
1421
1422         return iscsit_do_tx_data(conn, &c);
1423 }
1424
1425 void iscsit_collect_login_stats(
1426         struct iscsi_conn *conn,
1427         u8 status_class,
1428         u8 status_detail)
1429 {
1430         struct iscsi_param *intrname = NULL;
1431         struct iscsi_tiqn *tiqn;
1432         struct iscsi_login_stats *ls;
1433
1434         tiqn = iscsit_snmp_get_tiqn(conn);
1435         if (!tiqn)
1436                 return;
1437
1438         ls = &tiqn->login_stats;
1439
1440         spin_lock(&ls->lock);
1441         if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1442             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1443                 /* We already have the failure info for this login */
1444                 spin_unlock(&ls->lock);
1445                 return;
1446         }
1447
1448         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1449                 ls->accepts++;
1450         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1451                 ls->redirects++;
1452                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1453         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1454                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1455                 ls->authenticate_fails++;
1456                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1457         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1458                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1459                 ls->authorize_fails++;
1460                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1461         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1462                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1463                 ls->negotiate_fails++;
1464                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1465         } else {
1466                 ls->other_fails++;
1467                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1468         }
1469
1470         /* Save initiator name, ip address and time, if it is a failed login */
1471         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1472                 if (conn->param_list)
1473                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1474                                                              conn->param_list);
1475                 strcpy(ls->last_intr_fail_name,
1476                        (intrname ? intrname->value : "Unknown"));
1477
1478                 ls->last_intr_fail_ip_family = conn->login_family;
1479
1480                 snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1481                                 "%s", conn->login_ip);
1482                 ls->last_fail_time = get_jiffies_64();
1483         }
1484
1485         spin_unlock(&ls->lock);
1486 }
1487
1488 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1489 {
1490         struct iscsi_portal_group *tpg;
1491
1492         if (!conn || !conn->sess)
1493                 return NULL;
1494
1495         tpg = conn->sess->tpg;
1496         if (!tpg)
1497                 return NULL;
1498
1499         if (!tpg->tpg_tiqn)
1500                 return NULL;
1501
1502         return tpg->tpg_tiqn;
1503 }