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, ignoring.\n", cmdsn,
 246                        sess->max_cmd_sn);
 247                 ret = CMDSN_MAXCMDSN_OVERRUN;
 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         case CMDSN_MAXCMDSN_OVERRUN:
 307         default:
 308                 cmd->i_state = ISTATE_REMOVE;
 309                 iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 310                 /*
 311                  * Existing callers for iscsit_sequence_cmd() will silently
 312                  * ignore commands with CMDSN_LOWER_THAN_EXP, so force this
 313                  * return for CMDSN_MAXCMDSN_OVERRUN as well..
 314                  */
 315                 ret = CMDSN_LOWER_THAN_EXP;
 316                 break;
 317         }
 318         mutex_unlock(&conn->sess->cmdsn_mutex);
 319
 320         if (reject)
 321                 iscsit_reject_cmd(cmd, reason, buf);
 322
 323         return ret;
 324 }
 325 EXPORT_SYMBOL(iscsit_sequence_cmd);
 326
 327 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 328 {
 329         struct iscsi_conn *conn = cmd->conn;
 330         struct se_cmd *se_cmd = &cmd->se_cmd;
 331         struct iscsi_data *hdr = (struct iscsi_data *) buf;
 332         u32 payload_length = ntoh24(hdr->dlength);
 333
 334         if (conn->sess->sess_ops->InitialR2T) {
 335                 pr_err("Received unexpected unsolicited data"
 336                         " while InitialR2T=Yes, protocol error.\n");
 337                 transport_send_check_condition_and_sense(se_cmd,
 338                                 TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 339                 return -1;
 340         }
 341
 342         if ((cmd->first_burst_len + payload_length) >
 343              conn->sess->sess_ops->FirstBurstLength) {
 344                 pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 345                         " for this Unsolicited DataOut Burst.\n",
 346                         (cmd->first_burst_len + payload_length),
 347                                 conn->sess->sess_ops->FirstBurstLength);
 348                 transport_send_check_condition_and_sense(se_cmd,
 349                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 350                 return -1;
 351         }
 352
 353         if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 354                 return 0;
 355
 356         if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 357             ((cmd->first_burst_len + payload_length) !=
 358               conn->sess->sess_ops->FirstBurstLength)) {
 359                 pr_err("Unsolicited non-immediate data received %u"
 360                         " does not equal FirstBurstLength: %u, and does"
 361                         " not equal ExpXferLen %u.\n",
 362                         (cmd->first_burst_len + payload_length),
 363                         conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 364                 transport_send_check_condition_and_sense(se_cmd,
 365                                 TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 366                 return -1;
 367         }
 368         return 0;
 369 }
 370
 371 struct iscsi_cmd *iscsit_find_cmd_from_itt(
 372         struct iscsi_conn *conn,
 373         itt_t init_task_tag)
 374 {
 375         struct iscsi_cmd *cmd;
 376
 377         spin_lock_bh(&conn->cmd_lock);
 378         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 379                 if (cmd->init_task_tag == init_task_tag) {
 380                         spin_unlock_bh(&conn->cmd_lock);
 381                         return cmd;
 382                 }
 383         }
 384         spin_unlock_bh(&conn->cmd_lock);
 385
 386         pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 387                         init_task_tag, conn->cid);
 388         return NULL;
 389 }
 390
 391 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 392         struct iscsi_conn *conn,
 393         itt_t init_task_tag,
 394         u32 length)
 395 {
 396         struct iscsi_cmd *cmd;
 397
 398         spin_lock_bh(&conn->cmd_lock);
 399         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 400                 if (cmd->init_task_tag == init_task_tag) {
 401                         spin_unlock_bh(&conn->cmd_lock);
 402                         return cmd;
 403                 }
 404         }
 405         spin_unlock_bh(&conn->cmd_lock);
 406
 407         pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 408                         " dumping payload\n", init_task_tag, conn->cid);
 409         if (length)
 410                 iscsit_dump_data_payload(conn, length, 1);
 411
 412         return NULL;
 413 }
 414
 415 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 416         struct iscsi_conn *conn,
 417         u32 targ_xfer_tag)
 418 {
 419         struct iscsi_cmd *cmd = NULL;
 420
 421         spin_lock_bh(&conn->cmd_lock);
 422         list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 423                 if (cmd->targ_xfer_tag == targ_xfer_tag) {
 424                         spin_unlock_bh(&conn->cmd_lock);
 425                         return cmd;
 426                 }
 427         }
 428         spin_unlock_bh(&conn->cmd_lock);
 429
 430         pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 431                         targ_xfer_tag, conn->cid);
 432         return NULL;
 433 }
 434
 435 int iscsit_find_cmd_for_recovery(
 436         struct iscsi_session *sess,
 437         struct iscsi_cmd **cmd_ptr,
 438         struct iscsi_conn_recovery **cr_ptr,
 439         itt_t init_task_tag)
 440 {
 441         struct iscsi_cmd *cmd = NULL;
 442         struct iscsi_conn_recovery *cr;
 443         /*
 444          * Scan through the inactive connection recovery list's command list.
 445          * If init_task_tag matches the command is still alligent.
 446          */
 447         spin_lock(&sess->cr_i_lock);
 448         list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 449                 spin_lock(&cr->conn_recovery_cmd_lock);
 450                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 451                         if (cmd->init_task_tag == init_task_tag) {
 452                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 453                                 spin_unlock(&sess->cr_i_lock);
 454
 455                                 *cr_ptr = cr;
 456                                 *cmd_ptr = cmd;
 457                                 return -2;
 458                         }
 459                 }
 460                 spin_unlock(&cr->conn_recovery_cmd_lock);
 461         }
 462         spin_unlock(&sess->cr_i_lock);
 463         /*
 464          * Scan through the active connection recovery list's command list.
 465          * If init_task_tag matches the command is ready to be reassigned.
 466          */
 467         spin_lock(&sess->cr_a_lock);
 468         list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 469                 spin_lock(&cr->conn_recovery_cmd_lock);
 470                 list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 471                         if (cmd->init_task_tag == init_task_tag) {
 472                                 spin_unlock(&cr->conn_recovery_cmd_lock);
 473                                 spin_unlock(&sess->cr_a_lock);
 474
 475                                 *cr_ptr = cr;
 476                                 *cmd_ptr = cmd;
 477                                 return 0;
 478                         }
 479                 }
 480                 spin_unlock(&cr->conn_recovery_cmd_lock);
 481         }
 482         spin_unlock(&sess->cr_a_lock);
 483
 484         return -1;
 485 }
 486
 487 void iscsit_add_cmd_to_immediate_queue(
 488         struct iscsi_cmd *cmd,
 489         struct iscsi_conn *conn,
 490         u8 state)
 491 {
 492         struct iscsi_queue_req *qr;
 493
 494         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 495         if (!qr) {
 496                 pr_err("Unable to allocate memory for"
 497                                 " struct iscsi_queue_req\n");
 498                 return;
 499         }
 500         INIT_LIST_HEAD(&qr->qr_list);
 501         qr->cmd = cmd;
 502         qr->state = state;
 503
 504         spin_lock_bh(&conn->immed_queue_lock);
 505         list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 506         atomic_inc(&cmd->immed_queue_count);
 507         atomic_set(&conn->check_immediate_queue, 1);
 508         spin_unlock_bh(&conn->immed_queue_lock);
 509
 510         wake_up(&conn->queues_wq);
 511 }
 512
 513 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 514 {
 515         struct iscsi_queue_req *qr;
 516
 517         spin_lock_bh(&conn->immed_queue_lock);
 518         if (list_empty(&conn->immed_queue_list)) {
 519                 spin_unlock_bh(&conn->immed_queue_lock);
 520                 return NULL;
 521         }
 522         qr = list_first_entry(&conn->immed_queue_list,
 523                               struct iscsi_queue_req, qr_list);
 524
 525         list_del(&qr->qr_list);
 526         if (qr->cmd)
 527                 atomic_dec(&qr->cmd->immed_queue_count);
 528         spin_unlock_bh(&conn->immed_queue_lock);
 529
 530         return qr;
 531 }
 532
 533 static void iscsit_remove_cmd_from_immediate_queue(
 534         struct iscsi_cmd *cmd,
 535         struct iscsi_conn *conn)
 536 {
 537         struct iscsi_queue_req *qr, *qr_tmp;
 538
 539         spin_lock_bh(&conn->immed_queue_lock);
 540         if (!atomic_read(&cmd->immed_queue_count)) {
 541                 spin_unlock_bh(&conn->immed_queue_lock);
 542                 return;
 543         }
 544
 545         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 546                 if (qr->cmd != cmd)
 547                         continue;
 548
 549                 atomic_dec(&qr->cmd->immed_queue_count);
 550                 list_del(&qr->qr_list);
 551                 kmem_cache_free(lio_qr_cache, qr);
 552         }
 553         spin_unlock_bh(&conn->immed_queue_lock);
 554
 555         if (atomic_read(&cmd->immed_queue_count)) {
 556                 pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 557                         cmd->init_task_tag,
 558                         atomic_read(&cmd->immed_queue_count));
 559         }
 560 }
 561
 562 void iscsit_add_cmd_to_response_queue(
 563         struct iscsi_cmd *cmd,
 564         struct iscsi_conn *conn,
 565         u8 state)
 566 {
 567         struct iscsi_queue_req *qr;
 568
 569         qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 570         if (!qr) {
 571                 pr_err("Unable to allocate memory for"
 572                         " struct iscsi_queue_req\n");
 573                 return;
 574         }
 575         INIT_LIST_HEAD(&qr->qr_list);
 576         qr->cmd = cmd;
 577         qr->state = state;
 578
 579         spin_lock_bh(&conn->response_queue_lock);
 580         list_add_tail(&qr->qr_list, &conn->response_queue_list);
 581         atomic_inc(&cmd->response_queue_count);
 582         spin_unlock_bh(&conn->response_queue_lock);
 583
 584         wake_up(&conn->queues_wq);
 585 }
 586
 587 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 588 {
 589         struct iscsi_queue_req *qr;
 590
 591         spin_lock_bh(&conn->response_queue_lock);
 592         if (list_empty(&conn->response_queue_list)) {
 593                 spin_unlock_bh(&conn->response_queue_lock);
 594                 return NULL;
 595         }
 596
 597         qr = list_first_entry(&conn->response_queue_list,
 598                               struct iscsi_queue_req, qr_list);
 599
 600         list_del(&qr->qr_list);
 601         if (qr->cmd)
 602                 atomic_dec(&qr->cmd->response_queue_count);
 603         spin_unlock_bh(&conn->response_queue_lock);
 604
 605         return qr;
 606 }
 607
 608 static void iscsit_remove_cmd_from_response_queue(
 609         struct iscsi_cmd *cmd,
 610         struct iscsi_conn *conn)
 611 {
 612         struct iscsi_queue_req *qr, *qr_tmp;
 613
 614         spin_lock_bh(&conn->response_queue_lock);
 615         if (!atomic_read(&cmd->response_queue_count)) {
 616                 spin_unlock_bh(&conn->response_queue_lock);
 617                 return;
 618         }
 619
 620         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 621                                 qr_list) {
 622                 if (qr->cmd != cmd)
 623                         continue;
 624
 625                 atomic_dec(&qr->cmd->response_queue_count);
 626                 list_del(&qr->qr_list);
 627                 kmem_cache_free(lio_qr_cache, qr);
 628         }
 629         spin_unlock_bh(&conn->response_queue_lock);
 630
 631         if (atomic_read(&cmd->response_queue_count)) {
 632                 pr_err("ITT: 0x%08x response_queue_count: %d\n",
 633                         cmd->init_task_tag,
 634                         atomic_read(&cmd->response_queue_count));
 635         }
 636 }
 637
 638 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 639 {
 640         bool empty;
 641
 642         spin_lock_bh(&conn->immed_queue_lock);
 643         empty = list_empty(&conn->immed_queue_list);
 644         spin_unlock_bh(&conn->immed_queue_lock);
 645
 646         if (!empty)
 647                 return empty;
 648
 649         spin_lock_bh(&conn->response_queue_lock);
 650         empty = list_empty(&conn->response_queue_list);
 651         spin_unlock_bh(&conn->response_queue_lock);
 652
 653         return empty;
 654 }
 655
 656 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 657 {
 658         struct iscsi_queue_req *qr, *qr_tmp;
 659
 660         spin_lock_bh(&conn->immed_queue_lock);
 661         list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 662                 list_del(&qr->qr_list);
 663                 if (qr->cmd)
 664                         atomic_dec(&qr->cmd->immed_queue_count);
 665
 666                 kmem_cache_free(lio_qr_cache, qr);
 667         }
 668         spin_unlock_bh(&conn->immed_queue_lock);
 669
 670         spin_lock_bh(&conn->response_queue_lock);
 671         list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 672                         qr_list) {
 673                 list_del(&qr->qr_list);
 674                 if (qr->cmd)
 675                         atomic_dec(&qr->cmd->response_queue_count);
 676
 677                 kmem_cache_free(lio_qr_cache, qr);
 678         }
 679         spin_unlock_bh(&conn->response_queue_lock);
 680 }
 681
 682 void iscsit_release_cmd(struct iscsi_cmd *cmd)
 683 {
 684         struct iscsi_session *sess;
 685         struct se_cmd *se_cmd = &cmd->se_cmd;
 686
 687         if (cmd->conn)
 688                 sess = cmd->conn->sess;
 689         else
 690                 sess = cmd->sess;
 691
 692         BUG_ON(!sess || !sess->se_sess);
 693
 694         kfree(cmd->buf_ptr);
 695         kfree(cmd->pdu_list);
 696         kfree(cmd->seq_list);
 697         kfree(cmd->tmr_req);
 698         kfree(cmd->iov_data);
 699         kfree(cmd->text_in_ptr);
 700
 701         percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 702 }
 703 EXPORT_SYMBOL(iscsit_release_cmd);
 704
 705 static void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool scsi_cmd,
 706                               bool check_queues)
 707 {
 708         struct iscsi_conn *conn = cmd->conn;
 709
 710         if (scsi_cmd) {
 711                 if (cmd->data_direction == DMA_TO_DEVICE) {
 712                         iscsit_stop_dataout_timer(cmd);
 713                         iscsit_free_r2ts_from_list(cmd);
 714                 }
 715                 if (cmd->data_direction == DMA_FROM_DEVICE)
 716                         iscsit_free_all_datain_reqs(cmd);
 717         }
 718
 719         if (conn && check_queues) {
 720                 iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 721                 iscsit_remove_cmd_from_response_queue(cmd, conn);
 722         }
 723 }
 724
 725 void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 726 {
 727         struct se_cmd *se_cmd = NULL;
 728         int rc;
 729         /*
 730          * Determine if a struct se_cmd is associated with
 731          * this struct iscsi_cmd.
 732          */
 733         switch (cmd->iscsi_opcode) {
 734         case ISCSI_OP_SCSI_CMD:
 735                 se_cmd = &cmd->se_cmd;
 736                 __iscsit_free_cmd(cmd, true, shutdown);
 737                 /*
 738                  * Fallthrough
 739                  */
 740         case ISCSI_OP_SCSI_TMFUNC:
 741                 rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 742                 if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
 743                         __iscsit_free_cmd(cmd, true, shutdown);
 744                         target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 745                 }
 746                 break;
 747         case ISCSI_OP_REJECT:
 748                 /*
 749                  * Handle special case for REJECT when iscsi_add_reject*() has
 750                  * overwritten the original iscsi_opcode assignment, and the
 751                  * associated cmd->se_cmd needs to be released.
 752                  */
 753                 if (cmd->se_cmd.se_tfo != NULL) {
 754                         se_cmd = &cmd->se_cmd;
 755                         __iscsit_free_cmd(cmd, true, shutdown);
 756
 757                         rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 758                         if (!rc && shutdown && se_cmd->se_sess) {
 759                                 __iscsit_free_cmd(cmd, true, shutdown);
 760                                 target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 761                         }
 762                         break;
 763                 }
 764                 /* Fall-through */
 765         default:
 766                 __iscsit_free_cmd(cmd, false, shutdown);
 767                 iscsit_release_cmd(cmd);
 768                 break;
 769         }
 770 }
 771
 772 int iscsit_check_session_usage_count(struct iscsi_session *sess)
 773 {
 774         spin_lock_bh(&sess->session_usage_lock);
 775         if (sess->session_usage_count != 0) {
 776                 sess->session_waiting_on_uc = 1;
 777                 spin_unlock_bh(&sess->session_usage_lock);
 778                 if (in_interrupt())
 779                         return 2;
 780
 781                 wait_for_completion(&sess->session_waiting_on_uc_comp);
 782                 return 1;
 783         }
 784         spin_unlock_bh(&sess->session_usage_lock);
 785
 786         return 0;
 787 }
 788
 789 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 790 {
 791         spin_lock_bh(&sess->session_usage_lock);
 792         sess->session_usage_count--;
 793
 794         if (!sess->session_usage_count && sess->session_waiting_on_uc)
 795                 complete(&sess->session_waiting_on_uc_comp);
 796
 797         spin_unlock_bh(&sess->session_usage_lock);
 798 }
 799
 800 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 801 {
 802         spin_lock_bh(&sess->session_usage_lock);
 803         sess->session_usage_count++;
 804         spin_unlock_bh(&sess->session_usage_lock);
 805 }
 806
 807 /*
 808  *      Setup conn->if_marker and conn->of_marker values based upon
 809  *      the initial marker-less interval. (see iSCSI v19 A.2)
 810  */
 811 int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 812 {
 813         int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 814         /*
 815          * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 816          */
 817         u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 818         u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 819
 820         if (conn->conn_ops->OFMarker) {
 821                 /*
 822                  * Account for the first Login Command received not
 823                  * via iscsi_recv_msg().
 824                  */
 825                 conn->of_marker += ISCSI_HDR_LEN;
 826                 if (conn->of_marker <= OFMarkInt) {
 827                         conn->of_marker = (OFMarkInt - conn->of_marker);
 828                 } else {
 829                         login_ofmarker_count = (conn->of_marker / OFMarkInt);
 830                         next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 831                                         (login_ofmarker_count * MARKER_SIZE);
 832                         conn->of_marker = (next_marker - conn->of_marker);
 833                 }
 834                 conn->of_marker_offset = 0;
 835                 pr_debug("Setting OFMarker value to %u based on Initial"
 836                         " Markerless Interval.\n", conn->of_marker);
 837         }
 838
 839         if (conn->conn_ops->IFMarker) {
 840                 if (conn->if_marker <= IFMarkInt) {
 841                         conn->if_marker = (IFMarkInt - conn->if_marker);
 842                 } else {
 843                         login_ifmarker_count = (conn->if_marker / IFMarkInt);
 844                         next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 845                                         (login_ifmarker_count * MARKER_SIZE);
 846                         conn->if_marker = (next_marker - conn->if_marker);
 847                 }
 848                 pr_debug("Setting IFMarker value to %u based on Initial"
 849                         " Markerless Interval.\n", conn->if_marker);
 850         }
 851
 852         return 0;
 853 }
 854
 855 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 856 {
 857         struct iscsi_conn *conn;
 858
 859         spin_lock_bh(&sess->conn_lock);
 860         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 861                 if ((conn->cid == cid) &&
 862                     (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 863                         iscsit_inc_conn_usage_count(conn);
 864                         spin_unlock_bh(&sess->conn_lock);
 865                         return conn;
 866                 }
 867         }
 868         spin_unlock_bh(&sess->conn_lock);
 869
 870         return NULL;
 871 }
 872
 873 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 874 {
 875         struct iscsi_conn *conn;
 876
 877         spin_lock_bh(&sess->conn_lock);
 878         list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 879                 if (conn->cid == cid) {
 880                         iscsit_inc_conn_usage_count(conn);
 881                         spin_lock(&conn->state_lock);
 882                         atomic_set(&conn->connection_wait_rcfr, 1);
 883                         spin_unlock(&conn->state_lock);
 884                         spin_unlock_bh(&sess->conn_lock);
 885                         return conn;
 886                 }
 887         }
 888         spin_unlock_bh(&sess->conn_lock);
 889
 890         return NULL;
 891 }
 892
 893 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 894 {
 895         spin_lock_bh(&conn->conn_usage_lock);
 896         if (conn->conn_usage_count != 0) {
 897                 conn->conn_waiting_on_uc = 1;
 898                 spin_unlock_bh(&conn->conn_usage_lock);
 899
 900                 wait_for_completion(&conn->conn_waiting_on_uc_comp);
 901                 return;
 902         }
 903         spin_unlock_bh(&conn->conn_usage_lock);
 904 }
 905
 906 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 907 {
 908         spin_lock_bh(&conn->conn_usage_lock);
 909         conn->conn_usage_count--;
 910
 911         if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 912                 complete(&conn->conn_waiting_on_uc_comp);
 913
 914         spin_unlock_bh(&conn->conn_usage_lock);
 915 }
 916
 917 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 918 {
 919         spin_lock_bh(&conn->conn_usage_lock);
 920         conn->conn_usage_count++;
 921         spin_unlock_bh(&conn->conn_usage_lock);
 922 }
 923
 924 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 925 {
 926         u8 state;
 927         struct iscsi_cmd *cmd;
 928
 929         cmd = iscsit_allocate_cmd(conn, GFP_ATOMIC);
 930         if (!cmd)
 931                 return -1;
 932
 933         cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 934         state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 935                                 ISTATE_SEND_NOPIN_NO_RESPONSE;
 936         cmd->init_task_tag = RESERVED_ITT;
 937         spin_lock_bh(&conn->sess->ttt_lock);
 938         cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
 939                         0xFFFFFFFF;
 940         if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
 941                 cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
 942         spin_unlock_bh(&conn->sess->ttt_lock);
 943
 944         spin_lock_bh(&conn->cmd_lock);
 945         list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 946         spin_unlock_bh(&conn->cmd_lock);
 947
 948         if (want_response)
 949                 iscsit_start_nopin_response_timer(conn);
 950         iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 951
 952         return 0;
 953 }
 954
 955 static void iscsit_handle_nopin_response_timeout(unsigned long data)
 956 {
 957         struct iscsi_conn *conn = (struct iscsi_conn *) data;
 958
 959         iscsit_inc_conn_usage_count(conn);
 960
 961         spin_lock_bh(&conn->nopin_timer_lock);
 962         if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 963                 spin_unlock_bh(&conn->nopin_timer_lock);
 964                 iscsit_dec_conn_usage_count(conn);
 965                 return;
 966         }
 967
 968         pr_debug("Did not receive response to NOPIN on CID: %hu on"
 969                 " SID: %u, failing connection.\n", conn->cid,
 970                         conn->sess->sid);
 971         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 972         spin_unlock_bh(&conn->nopin_timer_lock);
 973
 974         {
 975         struct iscsi_portal_group *tpg = conn->sess->tpg;
 976         struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 977
 978         if (tiqn) {
 979                 spin_lock_bh(&tiqn->sess_err_stats.lock);
 980                 strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 981                                 conn->sess->sess_ops->InitiatorName);
 982                 tiqn->sess_err_stats.last_sess_failure_type =
 983                                 ISCSI_SESS_ERR_CXN_TIMEOUT;
 984                 tiqn->sess_err_stats.cxn_timeout_errors++;
 985                 atomic_long_inc(&conn->sess->conn_timeout_errors);
 986                 spin_unlock_bh(&tiqn->sess_err_stats.lock);
 987         }
 988         }
 989
 990         iscsit_cause_connection_reinstatement(conn, 0);
 991         iscsit_dec_conn_usage_count(conn);
 992 }
 993
 994 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 995 {
 996         struct iscsi_session *sess = conn->sess;
 997         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 998
 999         spin_lock_bh(&conn->nopin_timer_lock);
1000         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1001                 spin_unlock_bh(&conn->nopin_timer_lock);
1002                 return;
1003         }
1004
1005         mod_timer(&conn->nopin_response_timer,
1006                 (get_jiffies_64() + na->nopin_response_timeout * HZ));
1007         spin_unlock_bh(&conn->nopin_timer_lock);
1008 }
1009
1010 /*
1011  *      Called with conn->nopin_timer_lock held.
1012  */
1013 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
1014 {
1015         struct iscsi_session *sess = conn->sess;
1016         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1017
1018         spin_lock_bh(&conn->nopin_timer_lock);
1019         if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
1020                 spin_unlock_bh(&conn->nopin_timer_lock);
1021                 return;
1022         }
1023
1024         init_timer(&conn->nopin_response_timer);
1025         conn->nopin_response_timer.expires =
1026                 (get_jiffies_64() + na->nopin_response_timeout * HZ);
1027         conn->nopin_response_timer.data = (unsigned long)conn;
1028         conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
1029         conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
1030         conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
1031         add_timer(&conn->nopin_response_timer);
1032
1033         pr_debug("Started NOPIN Response Timer on CID: %d to %u"
1034                 " seconds\n", conn->cid, na->nopin_response_timeout);
1035         spin_unlock_bh(&conn->nopin_timer_lock);
1036 }
1037
1038 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
1039 {
1040         spin_lock_bh(&conn->nopin_timer_lock);
1041         if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1042                 spin_unlock_bh(&conn->nopin_timer_lock);
1043                 return;
1044         }
1045         conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1046         spin_unlock_bh(&conn->nopin_timer_lock);
1047
1048         del_timer_sync(&conn->nopin_response_timer);
1049
1050         spin_lock_bh(&conn->nopin_timer_lock);
1051         conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1052         spin_unlock_bh(&conn->nopin_timer_lock);
1053 }
1054
1055 static void iscsit_handle_nopin_timeout(unsigned long data)
1056 {
1057         struct iscsi_conn *conn = (struct iscsi_conn *) data;
1058
1059         iscsit_inc_conn_usage_count(conn);
1060
1061         spin_lock_bh(&conn->nopin_timer_lock);
1062         if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1063                 spin_unlock_bh(&conn->nopin_timer_lock);
1064                 iscsit_dec_conn_usage_count(conn);
1065                 return;
1066         }
1067         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1068         spin_unlock_bh(&conn->nopin_timer_lock);
1069
1070         iscsit_add_nopin(conn, 1);
1071         iscsit_dec_conn_usage_count(conn);
1072 }
1073
1074 /*
1075  * Called with conn->nopin_timer_lock held.
1076  */
1077 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1078 {
1079         struct iscsi_session *sess = conn->sess;
1080         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1081         /*
1082         * NOPIN timeout is disabled.
1083          */
1084         if (!na->nopin_timeout)
1085                 return;
1086
1087         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1088                 return;
1089
1090         init_timer(&conn->nopin_timer);
1091         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1092         conn->nopin_timer.data = (unsigned long)conn;
1093         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1094         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1095         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1096         add_timer(&conn->nopin_timer);
1097
1098         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1099                 " interval\n", conn->cid, na->nopin_timeout);
1100 }
1101
1102 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1103 {
1104         struct iscsi_session *sess = conn->sess;
1105         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1106         /*
1107          * NOPIN timeout is disabled..
1108          */
1109         if (!na->nopin_timeout)
1110                 return;
1111
1112         spin_lock_bh(&conn->nopin_timer_lock);
1113         if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1114                 spin_unlock_bh(&conn->nopin_timer_lock);
1115                 return;
1116         }
1117
1118         init_timer(&conn->nopin_timer);
1119         conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1120         conn->nopin_timer.data = (unsigned long)conn;
1121         conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1122         conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1123         conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1124         add_timer(&conn->nopin_timer);
1125
1126         pr_debug("Started NOPIN Timer on CID: %d at %u second"
1127                         " interval\n", conn->cid, na->nopin_timeout);
1128         spin_unlock_bh(&conn->nopin_timer_lock);
1129 }
1130
1131 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1132 {
1133         spin_lock_bh(&conn->nopin_timer_lock);
1134         if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1135                 spin_unlock_bh(&conn->nopin_timer_lock);
1136                 return;
1137         }
1138         conn->nopin_timer_flags |= ISCSI_TF_STOP;
1139         spin_unlock_bh(&conn->nopin_timer_lock);
1140
1141         del_timer_sync(&conn->nopin_timer);
1142
1143         spin_lock_bh(&conn->nopin_timer_lock);
1144         conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1145         spin_unlock_bh(&conn->nopin_timer_lock);
1146 }
1147
1148 int iscsit_send_tx_data(
1149         struct iscsi_cmd *cmd,
1150         struct iscsi_conn *conn,
1151         int use_misc)
1152 {
1153         int tx_sent, tx_size;
1154         u32 iov_count;
1155         struct kvec *iov;
1156
1157 send_data:
1158         tx_size = cmd->tx_size;
1159
1160         if (!use_misc) {
1161                 iov = &cmd->iov_data[0];
1162                 iov_count = cmd->iov_data_count;
1163         } else {
1164                 iov = &cmd->iov_misc[0];
1165                 iov_count = cmd->iov_misc_count;
1166         }
1167
1168         tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1169         if (tx_size != tx_sent) {
1170                 if (tx_sent == -EAGAIN) {
1171                         pr_err("tx_data() returned -EAGAIN\n");
1172                         goto send_data;
1173                 } else
1174                         return -1;
1175         }
1176         cmd->tx_size = 0;
1177
1178         return 0;
1179 }
1180
1181 int iscsit_fe_sendpage_sg(
1182         struct iscsi_cmd *cmd,
1183         struct iscsi_conn *conn)
1184 {
1185         struct scatterlist *sg = cmd->first_data_sg;
1186         struct kvec iov;
1187         u32 tx_hdr_size, data_len;
1188         u32 offset = cmd->first_data_sg_off;
1189         int tx_sent, iov_off;
1190
1191 send_hdr:
1192         tx_hdr_size = ISCSI_HDR_LEN;
1193         if (conn->conn_ops->HeaderDigest)
1194                 tx_hdr_size += ISCSI_CRC_LEN;
1195
1196         iov.iov_base = cmd->pdu;
1197         iov.iov_len = tx_hdr_size;
1198
1199         tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1200         if (tx_hdr_size != tx_sent) {
1201                 if (tx_sent == -EAGAIN) {
1202                         pr_err("tx_data() returned -EAGAIN\n");
1203                         goto send_hdr;
1204                 }
1205                 return -1;
1206         }
1207
1208         data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1209         /*
1210          * Set iov_off used by padding and data digest tx_data() calls below
1211          * in order to determine proper offset into cmd->iov_data[]
1212          */
1213         if (conn->conn_ops->DataDigest) {
1214                 data_len -= ISCSI_CRC_LEN;
1215                 if (cmd->padding)
1216                         iov_off = (cmd->iov_data_count - 2);
1217                 else
1218                         iov_off = (cmd->iov_data_count - 1);
1219         } else {
1220                 iov_off = (cmd->iov_data_count - 1);
1221         }
1222         /*
1223          * Perform sendpage() for each page in the scatterlist
1224          */
1225         while (data_len) {
1226                 u32 space = (sg->length - offset);
1227                 u32 sub_len = min_t(u32, data_len, space);
1228 send_pg:
1229                 tx_sent = conn->sock->ops->sendpage(conn->sock,
1230                                         sg_page(sg), sg->offset + offset, sub_len, 0);
1231                 if (tx_sent != sub_len) {
1232                         if (tx_sent == -EAGAIN) {
1233                                 pr_err("tcp_sendpage() returned"
1234                                                 " -EAGAIN\n");
1235                                 goto send_pg;
1236                         }
1237
1238                         pr_err("tcp_sendpage() failure: %d\n",
1239                                         tx_sent);
1240                         return -1;
1241                 }
1242
1243                 data_len -= sub_len;
1244                 offset = 0;
1245                 sg = sg_next(sg);
1246         }
1247
1248 send_padding:
1249         if (cmd->padding) {
1250                 struct kvec *iov_p = &cmd->iov_data[iov_off++];
1251
1252                 tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1253                 if (cmd->padding != tx_sent) {
1254                         if (tx_sent == -EAGAIN) {
1255                                 pr_err("tx_data() returned -EAGAIN\n");
1256                                 goto send_padding;
1257                         }
1258                         return -1;
1259                 }
1260         }
1261
1262 send_datacrc:
1263         if (conn->conn_ops->DataDigest) {
1264                 struct kvec *iov_d = &cmd->iov_data[iov_off];
1265
1266                 tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1267                 if (ISCSI_CRC_LEN != tx_sent) {
1268                         if (tx_sent == -EAGAIN) {
1269                                 pr_err("tx_data() returned -EAGAIN\n");
1270                                 goto send_datacrc;
1271                         }
1272                         return -1;
1273                 }
1274         }
1275
1276         return 0;
1277 }
1278
1279 /*
1280  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1281  *      back to the Initiator when an expection condition occurs with the
1282  *      errors set in status_class and status_detail.
1283  *
1284  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1285  *      Returns:        0 on success, -1 on error.
1286  */
1287 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1288 {
1289         struct iscsi_login_rsp *hdr;
1290         struct iscsi_login *login = conn->conn_login;
1291
1292         login->login_failed = 1;
1293         iscsit_collect_login_stats(conn, status_class, status_detail);
1294
1295         hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1296         hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1297         hdr->status_class       = status_class;
1298         hdr->status_detail      = status_detail;
1299         hdr->itt                = conn->login_itt;
1300
1301         return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1302 }
1303
1304 void iscsit_print_session_params(struct iscsi_session *sess)
1305 {
1306         struct iscsi_conn *conn;
1307
1308         pr_debug("-----------------------------[Session Params for"
1309                 " SID: %u]-----------------------------\n", sess->sid);
1310         spin_lock_bh(&sess->conn_lock);
1311         list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1312                 iscsi_dump_conn_ops(conn->conn_ops);
1313         spin_unlock_bh(&sess->conn_lock);
1314
1315         iscsi_dump_sess_ops(sess->sess_ops);
1316 }
1317
1318 static int iscsit_do_rx_data(
1319         struct iscsi_conn *conn,
1320         struct iscsi_data_count *count)
1321 {
1322         int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
1323         struct kvec *iov_p;
1324         struct msghdr msg;
1325
1326         if (!conn || !conn->sock || !conn->conn_ops)
1327                 return -1;
1328
1329         memset(&msg, 0, sizeof(struct msghdr));
1330
1331         iov_p = count->iov;
1332         iov_len = count->iov_count;
1333
1334         while (total_rx < data) {
1335                 rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
1336                                         (data - total_rx), MSG_WAITALL);
1337                 if (rx_loop <= 0) {
1338                         pr_debug("rx_loop: %d total_rx: %d\n",
1339                                 rx_loop, total_rx);
1340                         return rx_loop;
1341                 }
1342                 total_rx += rx_loop;
1343                 pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1344                                 rx_loop, total_rx, data);
1345         }
1346
1347         return total_rx;
1348 }
1349
1350 static int iscsit_do_tx_data(
1351         struct iscsi_conn *conn,
1352         struct iscsi_data_count *count)
1353 {
1354         int data = count->data_length, total_tx = 0, tx_loop = 0, iov_len;
1355         struct kvec *iov_p;
1356         struct msghdr msg;
1357
1358         if (!conn || !conn->sock || !conn->conn_ops)
1359                 return -1;
1360
1361         if (data <= 0) {
1362                 pr_err("Data length is: %d\n", data);
1363                 return -1;
1364         }
1365
1366         memset(&msg, 0, sizeof(struct msghdr));
1367
1368         iov_p = count->iov;
1369         iov_len = count->iov_count;
1370
1371         while (total_tx < data) {
1372                 tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1373                                         (data - total_tx));
1374                 if (tx_loop <= 0) {
1375                         pr_debug("tx_loop: %d total_tx %d\n",
1376                                 tx_loop, total_tx);
1377                         return tx_loop;
1378                 }
1379                 total_tx += tx_loop;
1380                 pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1381                                         tx_loop, total_tx, data);
1382         }
1383
1384         return total_tx;
1385 }
1386
1387 int rx_data(
1388         struct iscsi_conn *conn,
1389         struct kvec *iov,
1390         int iov_count,
1391         int data)
1392 {
1393         struct iscsi_data_count c;
1394
1395         if (!conn || !conn->sock || !conn->conn_ops)
1396                 return -1;
1397
1398         memset(&c, 0, sizeof(struct iscsi_data_count));
1399         c.iov = iov;
1400         c.iov_count = iov_count;
1401         c.data_length = data;
1402         c.type = ISCSI_RX_DATA;
1403
1404         return iscsit_do_rx_data(conn, &c);
1405 }
1406
1407 int tx_data(
1408         struct iscsi_conn *conn,
1409         struct kvec *iov,
1410         int iov_count,
1411         int data)
1412 {
1413         struct iscsi_data_count c;
1414
1415         if (!conn || !conn->sock || !conn->conn_ops)
1416                 return -1;
1417
1418         memset(&c, 0, sizeof(struct iscsi_data_count));
1419         c.iov = iov;
1420         c.iov_count = iov_count;
1421         c.data_length = data;
1422         c.type = ISCSI_TX_DATA;
1423
1424         return iscsit_do_tx_data(conn, &c);
1425 }
1426
1427 void iscsit_collect_login_stats(
1428         struct iscsi_conn *conn,
1429         u8 status_class,
1430         u8 status_detail)
1431 {
1432         struct iscsi_param *intrname = NULL;
1433         struct iscsi_tiqn *tiqn;
1434         struct iscsi_login_stats *ls;
1435
1436         tiqn = iscsit_snmp_get_tiqn(conn);
1437         if (!tiqn)
1438                 return;
1439
1440         ls = &tiqn->login_stats;
1441
1442         spin_lock(&ls->lock);
1443         if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1444             ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1445                 /* We already have the failure info for this login */
1446                 spin_unlock(&ls->lock);
1447                 return;
1448         }
1449
1450         if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1451                 ls->accepts++;
1452         else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1453                 ls->redirects++;
1454                 ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1455         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1456                  (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1457                 ls->authenticate_fails++;
1458                 ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1459         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1460                  (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1461                 ls->authorize_fails++;
1462                 ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1463         } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1464                  (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1465                 ls->negotiate_fails++;
1466                 ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1467         } else {
1468                 ls->other_fails++;
1469                 ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1470         }
1471
1472         /* Save initiator name, ip address and time, if it is a failed login */
1473         if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1474                 if (conn->param_list)
1475                         intrname = iscsi_find_param_from_key(INITIATORNAME,
1476                                                              conn->param_list);
1477                 strcpy(ls->last_intr_fail_name,
1478                        (intrname ? intrname->value : "Unknown"));
1479
1480                 ls->last_intr_fail_ip_family = conn->login_family;
1481
1482                 snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1483                                 "%s", conn->login_ip);
1484                 ls->last_fail_time = get_jiffies_64();
1485         }
1486
1487         spin_unlock(&ls->lock);
1488 }
1489
1490 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1491 {
1492         struct iscsi_portal_group *tpg;
1493
1494         if (!conn || !conn->sess)
1495                 return NULL;
1496
1497         tpg = conn->sess->tpg;
1498         if (!tpg)
1499                 return NULL;
1500
1501         if (!tpg->tpg_tiqn)
1502                 return NULL;
1503
1504         return tpg->tpg_tiqn;
1505 }