linux/drivers/target/iscsi/iscsi_target_util.c
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   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/iscsi/iscsi_transport.h>
  26
  27#include <target/iscsi/iscsi_target_core.h>
  28#include "iscsi_target_parameters.h"
  29#include "iscsi_target_seq_pdu_list.h"
  30#include "iscsi_target_datain_values.h"
  31#include "iscsi_target_erl0.h"
  32#include "iscsi_target_erl1.h"
  33#include "iscsi_target_erl2.h"
  34#include "iscsi_target_tpg.h"
  35#include "iscsi_target_util.h"
  36#include "iscsi_target.h"
  37
  38#define PRINT_BUFF(buff, len)                                   \
  39{                                                               \
  40        int zzz;                                                \
  41                                                                \
  42        pr_debug("%d:\n", __LINE__);                            \
  43        for (zzz = 0; zzz < len; zzz++) {                       \
  44                if (zzz % 16 == 0) {                            \
  45                        if (zzz)                                \
  46                                pr_debug("\n");                 \
  47                        pr_debug("%4i: ", zzz);                 \
  48                }                                               \
  49                pr_debug("%02x ", (unsigned char) (buff)[zzz]); \
  50        }                                                       \
  51        if ((len + 1) % 16)                                     \
  52                pr_debug("\n");                                 \
  53}
  54
  55extern struct list_head g_tiqn_list;
  56extern spinlock_t tiqn_lock;
  57
  58/*
  59 *      Called with cmd->r2t_lock held.
  60 */
  61int iscsit_add_r2t_to_list(
  62        struct iscsi_cmd *cmd,
  63        u32 offset,
  64        u32 xfer_len,
  65        int recovery,
  66        u32 r2t_sn)
  67{
  68        struct iscsi_r2t *r2t;
  69
  70        r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
  71        if (!r2t) {
  72                pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
  73                return -1;
  74        }
  75        INIT_LIST_HEAD(&r2t->r2t_list);
  76
  77        r2t->recovery_r2t = recovery;
  78        r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
  79        r2t->offset = offset;
  80        r2t->xfer_len = xfer_len;
  81        list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
  82        spin_unlock_bh(&cmd->r2t_lock);
  83
  84        iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
  85
  86        spin_lock_bh(&cmd->r2t_lock);
  87        return 0;
  88}
  89
  90struct iscsi_r2t *iscsit_get_r2t_for_eos(
  91        struct iscsi_cmd *cmd,
  92        u32 offset,
  93        u32 length)
  94{
  95        struct iscsi_r2t *r2t;
  96
  97        spin_lock_bh(&cmd->r2t_lock);
  98        list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
  99                if ((r2t->offset <= offset) &&
 100                    (r2t->offset + r2t->xfer_len) >= (offset + length)) {
 101                        spin_unlock_bh(&cmd->r2t_lock);
 102                        return r2t;
 103                }
 104        }
 105        spin_unlock_bh(&cmd->r2t_lock);
 106
 107        pr_err("Unable to locate R2T for Offset: %u, Length:"
 108                        " %u\n", offset, length);
 109        return NULL;
 110}
 111
 112struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
 113{
 114        struct iscsi_r2t *r2t;
 115
 116        spin_lock_bh(&cmd->r2t_lock);
 117        list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 118                if (!r2t->sent_r2t) {
 119                        spin_unlock_bh(&cmd->r2t_lock);
 120                        return r2t;
 121                }
 122        }
 123        spin_unlock_bh(&cmd->r2t_lock);
 124
 125        pr_err("Unable to locate next R2T to send for ITT:"
 126                        " 0x%08x.\n", cmd->init_task_tag);
 127        return NULL;
 128}
 129
 130/*
 131 *      Called with cmd->r2t_lock held.
 132 */
 133void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
 134{
 135        list_del(&r2t->r2t_list);
 136        kmem_cache_free(lio_r2t_cache, r2t);
 137}
 138
 139void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
 140{
 141        struct iscsi_r2t *r2t, *r2t_tmp;
 142
 143        spin_lock_bh(&cmd->r2t_lock);
 144        list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
 145                iscsit_free_r2t(r2t, cmd);
 146        spin_unlock_bh(&cmd->r2t_lock);
 147}
 148
 149/*
 150 * May be called from software interrupt (timer) context for allocating
 151 * iSCSI NopINs.
 152 */
 153struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, int state)
 154{
 155        struct iscsi_cmd *cmd;
 156        struct se_session *se_sess = conn->sess->se_sess;
 157        int size, tag;
 158
 159        tag = percpu_ida_alloc(&se_sess->sess_tag_pool, state);
 160        if (tag < 0)
 161                return NULL;
 162
 163        size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
 164        cmd = (struct iscsi_cmd *)(se_sess->sess_cmd_map + (tag * size));
 165        memset(cmd, 0, size);
 166
 167        cmd->se_cmd.map_tag = tag;
 168        cmd->conn = conn;
 169        INIT_LIST_HEAD(&cmd->i_conn_node);
 170        INIT_LIST_HEAD(&cmd->datain_list);
 171        INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 172        spin_lock_init(&cmd->datain_lock);
 173        spin_lock_init(&cmd->dataout_timeout_lock);
 174        spin_lock_init(&cmd->istate_lock);
 175        spin_lock_init(&cmd->error_lock);
 176        spin_lock_init(&cmd->r2t_lock);
 177
 178        return cmd;
 179}
 180EXPORT_SYMBOL(iscsit_allocate_cmd);
 181
 182struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 183        struct iscsi_cmd *cmd,
 184        u32 seq_send_order)
 185{
 186        u32 i;
 187
 188        for (i = 0; i < cmd->seq_count; i++)
 189                if (cmd->seq_list[i].seq_send_order == seq_send_order)
 190                        return &cmd->seq_list[i];
 191
 192        return NULL;
 193}
 194
 195struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 196{
 197        u32 i;
 198
 199        if (!cmd->seq_list) {
 200                pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 201                return NULL;
 202        }
 203
 204        for (i = 0; i < cmd->seq_count; i++) {
 205                if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 206                        continue;
 207                if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 208                        cmd->seq_send_order++;
 209                        return &cmd->seq_list[i];
 210                }
 211        }
 212
 213        return NULL;
 214}
 215
 216struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 217        struct iscsi_cmd *cmd,
 218        u32 r2t_sn)
 219{
 220        struct iscsi_r2t *r2t;
 221
 222        spin_lock_bh(&cmd->r2t_lock);
 223        list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 224                if (r2t->r2t_sn == r2t_sn) {
 225                        spin_unlock_bh(&cmd->r2t_lock);
 226                        return r2t;
 227                }
 228        }
 229        spin_unlock_bh(&cmd->r2t_lock);
 230
 231        return NULL;
 232}
 233
 234static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 235{
 236        u32 max_cmdsn;
 237        int ret;
 238
 239        /*
 240         * This is the proper method of checking received CmdSN against
 241         * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 242         * or order CmdSNs due to multiple connection sessions and/or
 243         * CRC failures.
 244         */
 245        max_cmdsn = atomic_read(&sess->max_cmd_sn);
 246        if (iscsi_sna_gt(cmdsn, max_cmdsn)) {
 247                pr_err("Received CmdSN: 0x%08x is greater than"
 248                       " MaxCmdSN: 0x%08x, ignoring.\n", cmdsn, max_cmdsn);
 249                ret = CMDSN_MAXCMDSN_OVERRUN;
 250
 251        } else if (cmdsn == sess->exp_cmd_sn) {
 252                sess->exp_cmd_sn++;
 253                pr_debug("Received CmdSN matches ExpCmdSN,"
 254                      " incremented ExpCmdSN to: 0x%08x\n",
 255                      sess->exp_cmd_sn);
 256                ret = CMDSN_NORMAL_OPERATION;
 257
 258        } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 259                pr_debug("Received CmdSN: 0x%08x is greater"
 260                      " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 261                      cmdsn, sess->exp_cmd_sn);
 262                ret = CMDSN_HIGHER_THAN_EXP;
 263
 264        } else {
 265                pr_err("Received CmdSN: 0x%08x is less than"
 266                       " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 267                       sess->exp_cmd_sn);
 268                ret = CMDSN_LOWER_THAN_EXP;
 269        }
 270
 271        return ret;
 272}
 273
 274/*
 275 * Commands may be received out of order if MC/S is in use.
 276 * Ensure they are executed in CmdSN order.
 277 */
 278int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 279                        unsigned char *buf, __be32 cmdsn)
 280{
 281        int ret, cmdsn_ret;
 282        bool reject = false;
 283        u8 reason = ISCSI_REASON_BOOKMARK_NO_RESOURCES;
 284
 285        mutex_lock(&conn->sess->cmdsn_mutex);
 286
 287        cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
 288        switch (cmdsn_ret) {
 289        case CMDSN_NORMAL_OPERATION:
 290                ret = iscsit_execute_cmd(cmd, 0);
 291                if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 292                        iscsit_execute_ooo_cmdsns(conn->sess);
 293                else if (ret < 0) {
 294                        reject = true;
 295                        ret = CMDSN_ERROR_CANNOT_RECOVER;
 296                }
 297                break;
 298        case CMDSN_HIGHER_THAN_EXP:
 299                ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
 300                if (ret < 0) {
 301                        reject = true;
 302                        ret = CMDSN_ERROR_CANNOT_RECOVER;
 303                        break;
 304                }
 305                ret = CMDSN_HIGHER_THAN_EXP;
 306                break;
 307        case CMDSN_LOWER_THAN_EXP:
 308        case CMDSN_MAXCMDSN_OVERRUN:
 309        default:
 310                cmd->i_state = ISTATE_REMOVE;
 311                iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 312                /*
 313                 * Existing callers for iscsit_sequence_cmd() will silently
 314                 * ignore commands with CMDSN_LOWER_THAN_EXP, so force this
 315                 * return for CMDSN_MAXCMDSN_OVERRUN as well..
 316                 */
 317                ret = CMDSN_LOWER_THAN_EXP;
 318                break;
 319        }
 320        mutex_unlock(&conn->sess->cmdsn_mutex);
 321
 322        if (reject)
 323                iscsit_reject_cmd(cmd, reason, buf);
 324
 325        return ret;
 326}
 327EXPORT_SYMBOL(iscsit_sequence_cmd);
 328
 329int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 330{
 331        struct iscsi_conn *conn = cmd->conn;
 332        struct se_cmd *se_cmd = &cmd->se_cmd;
 333        struct iscsi_data *hdr = (struct iscsi_data *) buf;
 334        u32 payload_length = ntoh24(hdr->dlength);
 335
 336        if (conn->sess->sess_ops->InitialR2T) {
 337                pr_err("Received unexpected unsolicited data"
 338                        " while InitialR2T=Yes, protocol error.\n");
 339                transport_send_check_condition_and_sense(se_cmd,
 340                                TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 341                return -1;
 342        }
 343
 344        if ((cmd->first_burst_len + payload_length) >
 345             conn->sess->sess_ops->FirstBurstLength) {
 346                pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 347                        " for this Unsolicited DataOut Burst.\n",
 348                        (cmd->first_burst_len + payload_length),
 349                                conn->sess->sess_ops->FirstBurstLength);
 350                transport_send_check_condition_and_sense(se_cmd,
 351                                TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 352                return -1;
 353        }
 354
 355        if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 356                return 0;
 357
 358        if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 359            ((cmd->first_burst_len + payload_length) !=
 360              conn->sess->sess_ops->FirstBurstLength)) {
 361                pr_err("Unsolicited non-immediate data received %u"
 362                        " does not equal FirstBurstLength: %u, and does"
 363                        " not equal ExpXferLen %u.\n",
 364                        (cmd->first_burst_len + payload_length),
 365                        conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 366                transport_send_check_condition_and_sense(se_cmd,
 367                                TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 368                return -1;
 369        }
 370        return 0;
 371}
 372
 373struct iscsi_cmd *iscsit_find_cmd_from_itt(
 374        struct iscsi_conn *conn,
 375        itt_t init_task_tag)
 376{
 377        struct iscsi_cmd *cmd;
 378
 379        spin_lock_bh(&conn->cmd_lock);
 380        list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 381                if (cmd->init_task_tag == init_task_tag) {
 382                        spin_unlock_bh(&conn->cmd_lock);
 383                        return cmd;
 384                }
 385        }
 386        spin_unlock_bh(&conn->cmd_lock);
 387
 388        pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 389                        init_task_tag, conn->cid);
 390        return NULL;
 391}
 392EXPORT_SYMBOL(iscsit_find_cmd_from_itt);
 393
 394struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 395        struct iscsi_conn *conn,
 396        itt_t init_task_tag,
 397        u32 length)
 398{
 399        struct iscsi_cmd *cmd;
 400
 401        spin_lock_bh(&conn->cmd_lock);
 402        list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 403                if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT)
 404                        continue;
 405                if (cmd->init_task_tag == init_task_tag) {
 406                        spin_unlock_bh(&conn->cmd_lock);
 407                        return cmd;
 408                }
 409        }
 410        spin_unlock_bh(&conn->cmd_lock);
 411
 412        pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 413                        " dumping payload\n", init_task_tag, conn->cid);
 414        if (length)
 415                iscsit_dump_data_payload(conn, length, 1);
 416
 417        return NULL;
 418}
 419
 420struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 421        struct iscsi_conn *conn,
 422        u32 targ_xfer_tag)
 423{
 424        struct iscsi_cmd *cmd = NULL;
 425
 426        spin_lock_bh(&conn->cmd_lock);
 427        list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 428                if (cmd->targ_xfer_tag == targ_xfer_tag) {
 429                        spin_unlock_bh(&conn->cmd_lock);
 430                        return cmd;
 431                }
 432        }
 433        spin_unlock_bh(&conn->cmd_lock);
 434
 435        pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 436                        targ_xfer_tag, conn->cid);
 437        return NULL;
 438}
 439
 440int iscsit_find_cmd_for_recovery(
 441        struct iscsi_session *sess,
 442        struct iscsi_cmd **cmd_ptr,
 443        struct iscsi_conn_recovery **cr_ptr,
 444        itt_t init_task_tag)
 445{
 446        struct iscsi_cmd *cmd = NULL;
 447        struct iscsi_conn_recovery *cr;
 448        /*
 449         * Scan through the inactive connection recovery list's command list.
 450         * If init_task_tag matches the command is still alligent.
 451         */
 452        spin_lock(&sess->cr_i_lock);
 453        list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 454                spin_lock(&cr->conn_recovery_cmd_lock);
 455                list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 456                        if (cmd->init_task_tag == init_task_tag) {
 457                                spin_unlock(&cr->conn_recovery_cmd_lock);
 458                                spin_unlock(&sess->cr_i_lock);
 459
 460                                *cr_ptr = cr;
 461                                *cmd_ptr = cmd;
 462                                return -2;
 463                        }
 464                }
 465                spin_unlock(&cr->conn_recovery_cmd_lock);
 466        }
 467        spin_unlock(&sess->cr_i_lock);
 468        /*
 469         * Scan through the active connection recovery list's command list.
 470         * If init_task_tag matches the command is ready to be reassigned.
 471         */
 472        spin_lock(&sess->cr_a_lock);
 473        list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 474                spin_lock(&cr->conn_recovery_cmd_lock);
 475                list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 476                        if (cmd->init_task_tag == init_task_tag) {
 477                                spin_unlock(&cr->conn_recovery_cmd_lock);
 478                                spin_unlock(&sess->cr_a_lock);
 479
 480                                *cr_ptr = cr;
 481                                *cmd_ptr = cmd;
 482                                return 0;
 483                        }
 484                }
 485                spin_unlock(&cr->conn_recovery_cmd_lock);
 486        }
 487        spin_unlock(&sess->cr_a_lock);
 488
 489        return -1;
 490}
 491
 492void iscsit_add_cmd_to_immediate_queue(
 493        struct iscsi_cmd *cmd,
 494        struct iscsi_conn *conn,
 495        u8 state)
 496{
 497        struct iscsi_queue_req *qr;
 498
 499        qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 500        if (!qr) {
 501                pr_err("Unable to allocate memory for"
 502                                " struct iscsi_queue_req\n");
 503                return;
 504        }
 505        INIT_LIST_HEAD(&qr->qr_list);
 506        qr->cmd = cmd;
 507        qr->state = state;
 508
 509        spin_lock_bh(&conn->immed_queue_lock);
 510        list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 511        atomic_inc(&cmd->immed_queue_count);
 512        atomic_set(&conn->check_immediate_queue, 1);
 513        spin_unlock_bh(&conn->immed_queue_lock);
 514
 515        wake_up(&conn->queues_wq);
 516}
 517EXPORT_SYMBOL(iscsit_add_cmd_to_immediate_queue);
 518
 519struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 520{
 521        struct iscsi_queue_req *qr;
 522
 523        spin_lock_bh(&conn->immed_queue_lock);
 524        if (list_empty(&conn->immed_queue_list)) {
 525                spin_unlock_bh(&conn->immed_queue_lock);
 526                return NULL;
 527        }
 528        qr = list_first_entry(&conn->immed_queue_list,
 529                              struct iscsi_queue_req, qr_list);
 530
 531        list_del(&qr->qr_list);
 532        if (qr->cmd)
 533                atomic_dec(&qr->cmd->immed_queue_count);
 534        spin_unlock_bh(&conn->immed_queue_lock);
 535
 536        return qr;
 537}
 538
 539static void iscsit_remove_cmd_from_immediate_queue(
 540        struct iscsi_cmd *cmd,
 541        struct iscsi_conn *conn)
 542{
 543        struct iscsi_queue_req *qr, *qr_tmp;
 544
 545        spin_lock_bh(&conn->immed_queue_lock);
 546        if (!atomic_read(&cmd->immed_queue_count)) {
 547                spin_unlock_bh(&conn->immed_queue_lock);
 548                return;
 549        }
 550
 551        list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 552                if (qr->cmd != cmd)
 553                        continue;
 554
 555                atomic_dec(&qr->cmd->immed_queue_count);
 556                list_del(&qr->qr_list);
 557                kmem_cache_free(lio_qr_cache, qr);
 558        }
 559        spin_unlock_bh(&conn->immed_queue_lock);
 560
 561        if (atomic_read(&cmd->immed_queue_count)) {
 562                pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 563                        cmd->init_task_tag,
 564                        atomic_read(&cmd->immed_queue_count));
 565        }
 566}
 567
 568void iscsit_add_cmd_to_response_queue(
 569        struct iscsi_cmd *cmd,
 570        struct iscsi_conn *conn,
 571        u8 state)
 572{
 573        struct iscsi_queue_req *qr;
 574
 575        qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 576        if (!qr) {
 577                pr_err("Unable to allocate memory for"
 578                        " struct iscsi_queue_req\n");
 579                return;
 580        }
 581        INIT_LIST_HEAD(&qr->qr_list);
 582        qr->cmd = cmd;
 583        qr->state = state;
 584
 585        spin_lock_bh(&conn->response_queue_lock);
 586        list_add_tail(&qr->qr_list, &conn->response_queue_list);
 587        atomic_inc(&cmd->response_queue_count);
 588        spin_unlock_bh(&conn->response_queue_lock);
 589
 590        wake_up(&conn->queues_wq);
 591}
 592
 593struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 594{
 595        struct iscsi_queue_req *qr;
 596
 597        spin_lock_bh(&conn->response_queue_lock);
 598        if (list_empty(&conn->response_queue_list)) {
 599                spin_unlock_bh(&conn->response_queue_lock);
 600                return NULL;
 601        }
 602
 603        qr = list_first_entry(&conn->response_queue_list,
 604                              struct iscsi_queue_req, qr_list);
 605
 606        list_del(&qr->qr_list);
 607        if (qr->cmd)
 608                atomic_dec(&qr->cmd->response_queue_count);
 609        spin_unlock_bh(&conn->response_queue_lock);
 610
 611        return qr;
 612}
 613
 614static void iscsit_remove_cmd_from_response_queue(
 615        struct iscsi_cmd *cmd,
 616        struct iscsi_conn *conn)
 617{
 618        struct iscsi_queue_req *qr, *qr_tmp;
 619
 620        spin_lock_bh(&conn->response_queue_lock);
 621        if (!atomic_read(&cmd->response_queue_count)) {
 622                spin_unlock_bh(&conn->response_queue_lock);
 623                return;
 624        }
 625
 626        list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 627                                qr_list) {
 628                if (qr->cmd != cmd)
 629                        continue;
 630
 631                atomic_dec(&qr->cmd->response_queue_count);
 632                list_del(&qr->qr_list);
 633                kmem_cache_free(lio_qr_cache, qr);
 634        }
 635        spin_unlock_bh(&conn->response_queue_lock);
 636
 637        if (atomic_read(&cmd->response_queue_count)) {
 638                pr_err("ITT: 0x%08x response_queue_count: %d\n",
 639                        cmd->init_task_tag,
 640                        atomic_read(&cmd->response_queue_count));
 641        }
 642}
 643
 644bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 645{
 646        bool empty;
 647
 648        spin_lock_bh(&conn->immed_queue_lock);
 649        empty = list_empty(&conn->immed_queue_list);
 650        spin_unlock_bh(&conn->immed_queue_lock);
 651
 652        if (!empty)
 653                return empty;
 654
 655        spin_lock_bh(&conn->response_queue_lock);
 656        empty = list_empty(&conn->response_queue_list);
 657        spin_unlock_bh(&conn->response_queue_lock);
 658
 659        return empty;
 660}
 661
 662void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 663{
 664        struct iscsi_queue_req *qr, *qr_tmp;
 665
 666        spin_lock_bh(&conn->immed_queue_lock);
 667        list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 668                list_del(&qr->qr_list);
 669                if (qr->cmd)
 670                        atomic_dec(&qr->cmd->immed_queue_count);
 671
 672                kmem_cache_free(lio_qr_cache, qr);
 673        }
 674        spin_unlock_bh(&conn->immed_queue_lock);
 675
 676        spin_lock_bh(&conn->response_queue_lock);
 677        list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 678                        qr_list) {
 679                list_del(&qr->qr_list);
 680                if (qr->cmd)
 681                        atomic_dec(&qr->cmd->response_queue_count);
 682
 683                kmem_cache_free(lio_qr_cache, qr);
 684        }
 685        spin_unlock_bh(&conn->response_queue_lock);
 686}
 687
 688void iscsit_release_cmd(struct iscsi_cmd *cmd)
 689{
 690        struct iscsi_session *sess;
 691        struct se_cmd *se_cmd = &cmd->se_cmd;
 692
 693        if (cmd->conn)
 694                sess = cmd->conn->sess;
 695        else
 696                sess = cmd->sess;
 697
 698        BUG_ON(!sess || !sess->se_sess);
 699
 700        kfree(cmd->buf_ptr);
 701        kfree(cmd->pdu_list);
 702        kfree(cmd->seq_list);
 703        kfree(cmd->tmr_req);
 704        kfree(cmd->iov_data);
 705        kfree(cmd->text_in_ptr);
 706
 707        percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 708}
 709EXPORT_SYMBOL(iscsit_release_cmd);
 710
 711void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool scsi_cmd,
 712                       bool check_queues)
 713{
 714        struct iscsi_conn *conn = cmd->conn;
 715
 716        if (scsi_cmd) {
 717                if (cmd->data_direction == DMA_TO_DEVICE) {
 718                        iscsit_stop_dataout_timer(cmd);
 719                        iscsit_free_r2ts_from_list(cmd);
 720                }
 721                if (cmd->data_direction == DMA_FROM_DEVICE)
 722                        iscsit_free_all_datain_reqs(cmd);
 723        }
 724
 725        if (conn && check_queues) {
 726                iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 727                iscsit_remove_cmd_from_response_queue(cmd, conn);
 728        }
 729
 730        if (conn && conn->conn_transport->iscsit_release_cmd)
 731                conn->conn_transport->iscsit_release_cmd(conn, cmd);
 732}
 733
 734void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 735{
 736        struct se_cmd *se_cmd = NULL;
 737        int rc;
 738        /*
 739         * Determine if a struct se_cmd is associated with
 740         * this struct iscsi_cmd.
 741         */
 742        switch (cmd->iscsi_opcode) {
 743        case ISCSI_OP_SCSI_CMD:
 744                se_cmd = &cmd->se_cmd;
 745                __iscsit_free_cmd(cmd, true, shutdown);
 746                /*
 747                 * Fallthrough
 748                 */
 749        case ISCSI_OP_SCSI_TMFUNC:
 750                rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 751                if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
 752                        __iscsit_free_cmd(cmd, true, shutdown);
 753                        target_put_sess_cmd(se_cmd);
 754                }
 755                break;
 756        case ISCSI_OP_REJECT:
 757                /*
 758                 * Handle special case for REJECT when iscsi_add_reject*() has
 759                 * overwritten the original iscsi_opcode assignment, and the
 760                 * associated cmd->se_cmd needs to be released.
 761                 */
 762                if (cmd->se_cmd.se_tfo != NULL) {
 763                        se_cmd = &cmd->se_cmd;
 764                        __iscsit_free_cmd(cmd, true, shutdown);
 765
 766                        rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 767                        if (!rc && shutdown && se_cmd->se_sess) {
 768                                __iscsit_free_cmd(cmd, true, shutdown);
 769                                target_put_sess_cmd(se_cmd);
 770                        }
 771                        break;
 772                }
 773                /* Fall-through */
 774        default:
 775                __iscsit_free_cmd(cmd, false, shutdown);
 776                iscsit_release_cmd(cmd);
 777                break;
 778        }
 779}
 780EXPORT_SYMBOL(iscsit_free_cmd);
 781
 782int iscsit_check_session_usage_count(struct iscsi_session *sess)
 783{
 784        spin_lock_bh(&sess->session_usage_lock);
 785        if (sess->session_usage_count != 0) {
 786                sess->session_waiting_on_uc = 1;
 787                spin_unlock_bh(&sess->session_usage_lock);
 788                if (in_interrupt())
 789                        return 2;
 790
 791                wait_for_completion(&sess->session_waiting_on_uc_comp);
 792                return 1;
 793        }
 794        spin_unlock_bh(&sess->session_usage_lock);
 795
 796        return 0;
 797}
 798
 799void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 800{
 801        spin_lock_bh(&sess->session_usage_lock);
 802        sess->session_usage_count--;
 803
 804        if (!sess->session_usage_count && sess->session_waiting_on_uc)
 805                complete(&sess->session_waiting_on_uc_comp);
 806
 807        spin_unlock_bh(&sess->session_usage_lock);
 808}
 809
 810void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 811{
 812        spin_lock_bh(&sess->session_usage_lock);
 813        sess->session_usage_count++;
 814        spin_unlock_bh(&sess->session_usage_lock);
 815}
 816
 817struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 818{
 819        struct iscsi_conn *conn;
 820
 821        spin_lock_bh(&sess->conn_lock);
 822        list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 823                if ((conn->cid == cid) &&
 824                    (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 825                        iscsit_inc_conn_usage_count(conn);
 826                        spin_unlock_bh(&sess->conn_lock);
 827                        return conn;
 828                }
 829        }
 830        spin_unlock_bh(&sess->conn_lock);
 831
 832        return NULL;
 833}
 834
 835struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 836{
 837        struct iscsi_conn *conn;
 838
 839        spin_lock_bh(&sess->conn_lock);
 840        list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 841                if (conn->cid == cid) {
 842                        iscsit_inc_conn_usage_count(conn);
 843                        spin_lock(&conn->state_lock);
 844                        atomic_set(&conn->connection_wait_rcfr, 1);
 845                        spin_unlock(&conn->state_lock);
 846                        spin_unlock_bh(&sess->conn_lock);
 847                        return conn;
 848                }
 849        }
 850        spin_unlock_bh(&sess->conn_lock);
 851
 852        return NULL;
 853}
 854
 855void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 856{
 857        spin_lock_bh(&conn->conn_usage_lock);
 858        if (conn->conn_usage_count != 0) {
 859                conn->conn_waiting_on_uc = 1;
 860                spin_unlock_bh(&conn->conn_usage_lock);
 861
 862                wait_for_completion(&conn->conn_waiting_on_uc_comp);
 863                return;
 864        }
 865        spin_unlock_bh(&conn->conn_usage_lock);
 866}
 867
 868void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 869{
 870        spin_lock_bh(&conn->conn_usage_lock);
 871        conn->conn_usage_count--;
 872
 873        if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 874                complete(&conn->conn_waiting_on_uc_comp);
 875
 876        spin_unlock_bh(&conn->conn_usage_lock);
 877}
 878
 879void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 880{
 881        spin_lock_bh(&conn->conn_usage_lock);
 882        conn->conn_usage_count++;
 883        spin_unlock_bh(&conn->conn_usage_lock);
 884}
 885
 886static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 887{
 888        u8 state;
 889        struct iscsi_cmd *cmd;
 890
 891        cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
 892        if (!cmd)
 893                return -1;
 894
 895        cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 896        state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 897                                ISTATE_SEND_NOPIN_NO_RESPONSE;
 898        cmd->init_task_tag = RESERVED_ITT;
 899        cmd->targ_xfer_tag = (want_response) ?
 900                             session_get_next_ttt(conn->sess) : 0xFFFFFFFF;
 901        spin_lock_bh(&conn->cmd_lock);
 902        list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 903        spin_unlock_bh(&conn->cmd_lock);
 904
 905        if (want_response)
 906                iscsit_start_nopin_response_timer(conn);
 907        iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 908
 909        return 0;
 910}
 911
 912static void iscsit_handle_nopin_response_timeout(unsigned long data)
 913{
 914        struct iscsi_conn *conn = (struct iscsi_conn *) data;
 915
 916        iscsit_inc_conn_usage_count(conn);
 917
 918        spin_lock_bh(&conn->nopin_timer_lock);
 919        if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 920                spin_unlock_bh(&conn->nopin_timer_lock);
 921                iscsit_dec_conn_usage_count(conn);
 922                return;
 923        }
 924
 925        pr_debug("Did not receive response to NOPIN on CID: %hu on"
 926                " SID: %u, failing connection.\n", conn->cid,
 927                        conn->sess->sid);
 928        conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 929        spin_unlock_bh(&conn->nopin_timer_lock);
 930
 931        {
 932        struct iscsi_portal_group *tpg = conn->sess->tpg;
 933        struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 934
 935        if (tiqn) {
 936                spin_lock_bh(&tiqn->sess_err_stats.lock);
 937                strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 938                                conn->sess->sess_ops->InitiatorName);
 939                tiqn->sess_err_stats.last_sess_failure_type =
 940                                ISCSI_SESS_ERR_CXN_TIMEOUT;
 941                tiqn->sess_err_stats.cxn_timeout_errors++;
 942                atomic_long_inc(&conn->sess->conn_timeout_errors);
 943                spin_unlock_bh(&tiqn->sess_err_stats.lock);
 944        }
 945        }
 946
 947        iscsit_cause_connection_reinstatement(conn, 0);
 948        iscsit_dec_conn_usage_count(conn);
 949}
 950
 951void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 952{
 953        struct iscsi_session *sess = conn->sess;
 954        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 955
 956        spin_lock_bh(&conn->nopin_timer_lock);
 957        if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
 958                spin_unlock_bh(&conn->nopin_timer_lock);
 959                return;
 960        }
 961
 962        mod_timer(&conn->nopin_response_timer,
 963                (get_jiffies_64() + na->nopin_response_timeout * HZ));
 964        spin_unlock_bh(&conn->nopin_timer_lock);
 965}
 966
 967/*
 968 *      Called with conn->nopin_timer_lock held.
 969 */
 970void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
 971{
 972        struct iscsi_session *sess = conn->sess;
 973        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
 974
 975        spin_lock_bh(&conn->nopin_timer_lock);
 976        if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
 977                spin_unlock_bh(&conn->nopin_timer_lock);
 978                return;
 979        }
 980
 981        init_timer(&conn->nopin_response_timer);
 982        conn->nopin_response_timer.expires =
 983                (get_jiffies_64() + na->nopin_response_timeout * HZ);
 984        conn->nopin_response_timer.data = (unsigned long)conn;
 985        conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
 986        conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
 987        conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
 988        add_timer(&conn->nopin_response_timer);
 989
 990        pr_debug("Started NOPIN Response Timer on CID: %d to %u"
 991                " seconds\n", conn->cid, na->nopin_response_timeout);
 992        spin_unlock_bh(&conn->nopin_timer_lock);
 993}
 994
 995void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
 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        conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1003        spin_unlock_bh(&conn->nopin_timer_lock);
1004
1005        del_timer_sync(&conn->nopin_response_timer);
1006
1007        spin_lock_bh(&conn->nopin_timer_lock);
1008        conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1009        spin_unlock_bh(&conn->nopin_timer_lock);
1010}
1011
1012static void iscsit_handle_nopin_timeout(unsigned long data)
1013{
1014        struct iscsi_conn *conn = (struct iscsi_conn *) data;
1015
1016        iscsit_inc_conn_usage_count(conn);
1017
1018        spin_lock_bh(&conn->nopin_timer_lock);
1019        if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1020                spin_unlock_bh(&conn->nopin_timer_lock);
1021                iscsit_dec_conn_usage_count(conn);
1022                return;
1023        }
1024        conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1025        spin_unlock_bh(&conn->nopin_timer_lock);
1026
1027        iscsit_add_nopin(conn, 1);
1028        iscsit_dec_conn_usage_count(conn);
1029}
1030
1031/*
1032 * Called with conn->nopin_timer_lock held.
1033 */
1034void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1035{
1036        struct iscsi_session *sess = conn->sess;
1037        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1038        /*
1039        * NOPIN timeout is disabled.
1040         */
1041        if (!na->nopin_timeout)
1042                return;
1043
1044        if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1045                return;
1046
1047        init_timer(&conn->nopin_timer);
1048        conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1049        conn->nopin_timer.data = (unsigned long)conn;
1050        conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1051        conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1052        conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1053        add_timer(&conn->nopin_timer);
1054
1055        pr_debug("Started NOPIN Timer on CID: %d at %u second"
1056                " interval\n", conn->cid, na->nopin_timeout);
1057}
1058
1059void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1060{
1061        struct iscsi_session *sess = conn->sess;
1062        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1063        /*
1064         * NOPIN timeout is disabled..
1065         */
1066        if (!na->nopin_timeout)
1067                return;
1068
1069        spin_lock_bh(&conn->nopin_timer_lock);
1070        if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1071                spin_unlock_bh(&conn->nopin_timer_lock);
1072                return;
1073        }
1074
1075        init_timer(&conn->nopin_timer);
1076        conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1077        conn->nopin_timer.data = (unsigned long)conn;
1078        conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1079        conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1080        conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1081        add_timer(&conn->nopin_timer);
1082
1083        pr_debug("Started NOPIN Timer on CID: %d at %u second"
1084                        " interval\n", conn->cid, na->nopin_timeout);
1085        spin_unlock_bh(&conn->nopin_timer_lock);
1086}
1087
1088void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1089{
1090        spin_lock_bh(&conn->nopin_timer_lock);
1091        if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1092                spin_unlock_bh(&conn->nopin_timer_lock);
1093                return;
1094        }
1095        conn->nopin_timer_flags |= ISCSI_TF_STOP;
1096        spin_unlock_bh(&conn->nopin_timer_lock);
1097
1098        del_timer_sync(&conn->nopin_timer);
1099
1100        spin_lock_bh(&conn->nopin_timer_lock);
1101        conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1102        spin_unlock_bh(&conn->nopin_timer_lock);
1103}
1104
1105int iscsit_send_tx_data(
1106        struct iscsi_cmd *cmd,
1107        struct iscsi_conn *conn,
1108        int use_misc)
1109{
1110        int tx_sent, tx_size;
1111        u32 iov_count;
1112        struct kvec *iov;
1113
1114send_data:
1115        tx_size = cmd->tx_size;
1116
1117        if (!use_misc) {
1118                iov = &cmd->iov_data[0];
1119                iov_count = cmd->iov_data_count;
1120        } else {
1121                iov = &cmd->iov_misc[0];
1122                iov_count = cmd->iov_misc_count;
1123        }
1124
1125        tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1126        if (tx_size != tx_sent) {
1127                if (tx_sent == -EAGAIN) {
1128                        pr_err("tx_data() returned -EAGAIN\n");
1129                        goto send_data;
1130                } else
1131                        return -1;
1132        }
1133        cmd->tx_size = 0;
1134
1135        return 0;
1136}
1137
1138int iscsit_fe_sendpage_sg(
1139        struct iscsi_cmd *cmd,
1140        struct iscsi_conn *conn)
1141{
1142        struct scatterlist *sg = cmd->first_data_sg;
1143        struct kvec iov;
1144        u32 tx_hdr_size, data_len;
1145        u32 offset = cmd->first_data_sg_off;
1146        int tx_sent, iov_off;
1147
1148send_hdr:
1149        tx_hdr_size = ISCSI_HDR_LEN;
1150        if (conn->conn_ops->HeaderDigest)
1151                tx_hdr_size += ISCSI_CRC_LEN;
1152
1153        iov.iov_base = cmd->pdu;
1154        iov.iov_len = tx_hdr_size;
1155
1156        tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1157        if (tx_hdr_size != tx_sent) {
1158                if (tx_sent == -EAGAIN) {
1159                        pr_err("tx_data() returned -EAGAIN\n");
1160                        goto send_hdr;
1161                }
1162                return -1;
1163        }
1164
1165        data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1166        /*
1167         * Set iov_off used by padding and data digest tx_data() calls below
1168         * in order to determine proper offset into cmd->iov_data[]
1169         */
1170        if (conn->conn_ops->DataDigest) {
1171                data_len -= ISCSI_CRC_LEN;
1172                if (cmd->padding)
1173                        iov_off = (cmd->iov_data_count - 2);
1174                else
1175                        iov_off = (cmd->iov_data_count - 1);
1176        } else {
1177                iov_off = (cmd->iov_data_count - 1);
1178        }
1179        /*
1180         * Perform sendpage() for each page in the scatterlist
1181         */
1182        while (data_len) {
1183                u32 space = (sg->length - offset);
1184                u32 sub_len = min_t(u32, data_len, space);
1185send_pg:
1186                tx_sent = conn->sock->ops->sendpage(conn->sock,
1187                                        sg_page(sg), sg->offset + offset, sub_len, 0);
1188                if (tx_sent != sub_len) {
1189                        if (tx_sent == -EAGAIN) {
1190                                pr_err("tcp_sendpage() returned"
1191                                                " -EAGAIN\n");
1192                                goto send_pg;
1193                        }
1194
1195                        pr_err("tcp_sendpage() failure: %d\n",
1196                                        tx_sent);
1197                        return -1;
1198                }
1199
1200                data_len -= sub_len;
1201                offset = 0;
1202                sg = sg_next(sg);
1203        }
1204
1205send_padding:
1206        if (cmd->padding) {
1207                struct kvec *iov_p = &cmd->iov_data[iov_off++];
1208
1209                tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1210                if (cmd->padding != tx_sent) {
1211                        if (tx_sent == -EAGAIN) {
1212                                pr_err("tx_data() returned -EAGAIN\n");
1213                                goto send_padding;
1214                        }
1215                        return -1;
1216                }
1217        }
1218
1219send_datacrc:
1220        if (conn->conn_ops->DataDigest) {
1221                struct kvec *iov_d = &cmd->iov_data[iov_off];
1222
1223                tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1224                if (ISCSI_CRC_LEN != tx_sent) {
1225                        if (tx_sent == -EAGAIN) {
1226                                pr_err("tx_data() returned -EAGAIN\n");
1227                                goto send_datacrc;
1228                        }
1229                        return -1;
1230                }
1231        }
1232
1233        return 0;
1234}
1235
1236/*
1237 *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1238 *      back to the Initiator when an expection condition occurs with the
1239 *      errors set in status_class and status_detail.
1240 *
1241 *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1242 *      Returns:        0 on success, -1 on error.
1243 */
1244int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1245{
1246        struct iscsi_login_rsp *hdr;
1247        struct iscsi_login *login = conn->conn_login;
1248
1249        login->login_failed = 1;
1250        iscsit_collect_login_stats(conn, status_class, status_detail);
1251
1252        memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1253
1254        hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1255        hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1256        hdr->status_class       = status_class;
1257        hdr->status_detail      = status_detail;
1258        hdr->itt                = conn->login_itt;
1259
1260        return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1261}
1262
1263void iscsit_print_session_params(struct iscsi_session *sess)
1264{
1265        struct iscsi_conn *conn;
1266
1267        pr_debug("-----------------------------[Session Params for"
1268                " SID: %u]-----------------------------\n", sess->sid);
1269        spin_lock_bh(&sess->conn_lock);
1270        list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1271                iscsi_dump_conn_ops(conn->conn_ops);
1272        spin_unlock_bh(&sess->conn_lock);
1273
1274        iscsi_dump_sess_ops(sess->sess_ops);
1275}
1276
1277static int iscsit_do_rx_data(
1278        struct iscsi_conn *conn,
1279        struct iscsi_data_count *count)
1280{
1281        int data = count->data_length, rx_loop = 0, total_rx = 0;
1282        struct msghdr msg;
1283
1284        if (!conn || !conn->sock || !conn->conn_ops)
1285                return -1;
1286
1287        memset(&msg, 0, sizeof(struct msghdr));
1288        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC,
1289                      count->iov, count->iov_count, data);
1290
1291        while (msg_data_left(&msg)) {
1292                rx_loop = sock_recvmsg(conn->sock, &msg, MSG_WAITALL);
1293                if (rx_loop <= 0) {
1294                        pr_debug("rx_loop: %d total_rx: %d\n",
1295                                rx_loop, total_rx);
1296                        return rx_loop;
1297                }
1298                total_rx += rx_loop;
1299                pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1300                                rx_loop, total_rx, data);
1301        }
1302
1303        return total_rx;
1304}
1305
1306static int iscsit_do_tx_data(
1307        struct iscsi_conn *conn,
1308        struct iscsi_data_count *count)
1309{
1310        int ret, iov_len;
1311        struct kvec *iov_p;
1312        struct msghdr msg;
1313
1314        if (!conn || !conn->sock || !conn->conn_ops)
1315                return -1;
1316
1317        if (count->data_length <= 0) {
1318                pr_err("Data length is: %d\n", count->data_length);
1319                return -1;
1320        }
1321
1322        memset(&msg, 0, sizeof(struct msghdr));
1323
1324        iov_p = count->iov;
1325        iov_len = count->iov_count;
1326
1327        ret = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1328                             count->data_length);
1329        if (ret != count->data_length) {
1330                pr_err("Unexpected ret: %d send data %d\n",
1331                       ret, count->data_length);
1332                return -EPIPE;
1333        }
1334        pr_debug("ret: %d, sent data: %d\n", ret, count->data_length);
1335
1336        return ret;
1337}
1338
1339int rx_data(
1340        struct iscsi_conn *conn,
1341        struct kvec *iov,
1342        int iov_count,
1343        int data)
1344{
1345        struct iscsi_data_count c;
1346
1347        if (!conn || !conn->sock || !conn->conn_ops)
1348                return -1;
1349
1350        memset(&c, 0, sizeof(struct iscsi_data_count));
1351        c.iov = iov;
1352        c.iov_count = iov_count;
1353        c.data_length = data;
1354        c.type = ISCSI_RX_DATA;
1355
1356        return iscsit_do_rx_data(conn, &c);
1357}
1358
1359int tx_data(
1360        struct iscsi_conn *conn,
1361        struct kvec *iov,
1362        int iov_count,
1363        int data)
1364{
1365        struct iscsi_data_count c;
1366
1367        if (!conn || !conn->sock || !conn->conn_ops)
1368                return -1;
1369
1370        memset(&c, 0, sizeof(struct iscsi_data_count));
1371        c.iov = iov;
1372        c.iov_count = iov_count;
1373        c.data_length = data;
1374        c.type = ISCSI_TX_DATA;
1375
1376        return iscsit_do_tx_data(conn, &c);
1377}
1378
1379static bool sockaddr_equal(struct sockaddr_storage *x, struct sockaddr_storage *y)
1380{
1381        switch (x->ss_family) {
1382        case AF_INET: {
1383                struct sockaddr_in *sinx = (struct sockaddr_in *)x;
1384                struct sockaddr_in *siny = (struct sockaddr_in *)y;
1385                if (sinx->sin_addr.s_addr != siny->sin_addr.s_addr)
1386                        return false;
1387                if (sinx->sin_port != siny->sin_port)
1388                        return false;
1389                break;
1390        }
1391        case AF_INET6: {
1392                struct sockaddr_in6 *sinx = (struct sockaddr_in6 *)x;
1393                struct sockaddr_in6 *siny = (struct sockaddr_in6 *)y;
1394                if (!ipv6_addr_equal(&sinx->sin6_addr, &siny->sin6_addr))
1395                        return false;
1396                if (sinx->sin6_port != siny->sin6_port)
1397                        return false;
1398                break;
1399        }
1400        default:
1401                return false;
1402        }
1403        return true;
1404}
1405
1406void iscsit_collect_login_stats(
1407        struct iscsi_conn *conn,
1408        u8 status_class,
1409        u8 status_detail)
1410{
1411        struct iscsi_param *intrname = NULL;
1412        struct iscsi_tiqn *tiqn;
1413        struct iscsi_login_stats *ls;
1414
1415        tiqn = iscsit_snmp_get_tiqn(conn);
1416        if (!tiqn)
1417                return;
1418
1419        ls = &tiqn->login_stats;
1420
1421        spin_lock(&ls->lock);
1422        if (sockaddr_equal(&conn->login_sockaddr, &ls->last_intr_fail_sockaddr) &&
1423            ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1424                /* We already have the failure info for this login */
1425                spin_unlock(&ls->lock);
1426                return;
1427        }
1428
1429        if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1430                ls->accepts++;
1431        else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1432                ls->redirects++;
1433                ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1434        } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1435                 (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1436                ls->authenticate_fails++;
1437                ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1438        } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1439                 (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1440                ls->authorize_fails++;
1441                ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1442        } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1443                 (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1444                ls->negotiate_fails++;
1445                ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1446        } else {
1447                ls->other_fails++;
1448                ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1449        }
1450
1451        /* Save initiator name, ip address and time, if it is a failed login */
1452        if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1453                if (conn->param_list)
1454                        intrname = iscsi_find_param_from_key(INITIATORNAME,
1455                                                             conn->param_list);
1456                strlcpy(ls->last_intr_fail_name,
1457                       (intrname ? intrname->value : "Unknown"),
1458                       sizeof(ls->last_intr_fail_name));
1459
1460                ls->last_intr_fail_ip_family = conn->login_family;
1461
1462                ls->last_intr_fail_sockaddr = conn->login_sockaddr;
1463                ls->last_fail_time = get_jiffies_64();
1464        }
1465
1466        spin_unlock(&ls->lock);
1467}
1468
1469struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1470{
1471        struct iscsi_portal_group *tpg;
1472
1473        if (!conn || !conn->sess)
1474                return NULL;
1475
1476        tpg = conn->sess->tpg;
1477        if (!tpg)
1478                return NULL;
1479
1480        if (!tpg->tpg_tiqn)
1481                return NULL;
1482
1483        return tpg->tpg_tiqn;
1484}
1485