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/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
  57extern struct list_head g_tiqn_list;
  58extern spinlock_t tiqn_lock;
  59
  60/*
  61 *      Called with cmd->r2t_lock held.
  62 */
  63int 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
  92struct 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
 114struct 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 */
 135void 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
 141void 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 */
 155struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, int state)
 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, state);
 162        if (tag < 0)
 163                return NULL;
 164
 165        size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
 166        cmd = (struct iscsi_cmd *)(se_sess->sess_cmd_map + (tag * size));
 167        memset(cmd, 0, size);
 168
 169        cmd->se_cmd.map_tag = tag;
 170        cmd->conn = conn;
 171        INIT_LIST_HEAD(&cmd->i_conn_node);
 172        INIT_LIST_HEAD(&cmd->datain_list);
 173        INIT_LIST_HEAD(&cmd->cmd_r2t_list);
 174        spin_lock_init(&cmd->datain_lock);
 175        spin_lock_init(&cmd->dataout_timeout_lock);
 176        spin_lock_init(&cmd->istate_lock);
 177        spin_lock_init(&cmd->error_lock);
 178        spin_lock_init(&cmd->r2t_lock);
 179
 180        return cmd;
 181}
 182EXPORT_SYMBOL(iscsit_allocate_cmd);
 183
 184struct iscsi_seq *iscsit_get_seq_holder_for_datain(
 185        struct iscsi_cmd *cmd,
 186        u32 seq_send_order)
 187{
 188        u32 i;
 189
 190        for (i = 0; i < cmd->seq_count; i++)
 191                if (cmd->seq_list[i].seq_send_order == seq_send_order)
 192                        return &cmd->seq_list[i];
 193
 194        return NULL;
 195}
 196
 197struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
 198{
 199        u32 i;
 200
 201        if (!cmd->seq_list) {
 202                pr_err("struct iscsi_cmd->seq_list is NULL!\n");
 203                return NULL;
 204        }
 205
 206        for (i = 0; i < cmd->seq_count; i++) {
 207                if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
 208                        continue;
 209                if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
 210                        cmd->seq_send_order++;
 211                        return &cmd->seq_list[i];
 212                }
 213        }
 214
 215        return NULL;
 216}
 217
 218struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
 219        struct iscsi_cmd *cmd,
 220        u32 r2t_sn)
 221{
 222        struct iscsi_r2t *r2t;
 223
 224        spin_lock_bh(&cmd->r2t_lock);
 225        list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
 226                if (r2t->r2t_sn == r2t_sn) {
 227                        spin_unlock_bh(&cmd->r2t_lock);
 228                        return r2t;
 229                }
 230        }
 231        spin_unlock_bh(&cmd->r2t_lock);
 232
 233        return NULL;
 234}
 235
 236static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
 237{
 238        int ret;
 239
 240        /*
 241         * This is the proper method of checking received CmdSN against
 242         * ExpCmdSN and MaxCmdSN values, as well as accounting for out
 243         * or order CmdSNs due to multiple connection sessions and/or
 244         * CRC failures.
 245         */
 246        if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) {
 247                pr_err("Received CmdSN: 0x%08x is greater than"
 248                       " MaxCmdSN: 0x%08x, ignoring.\n", cmdsn,
 249                       sess->max_cmd_sn);
 250                ret = CMDSN_MAXCMDSN_OVERRUN;
 251
 252        } else if (cmdsn == sess->exp_cmd_sn) {
 253                sess->exp_cmd_sn++;
 254                pr_debug("Received CmdSN matches ExpCmdSN,"
 255                      " incremented ExpCmdSN to: 0x%08x\n",
 256                      sess->exp_cmd_sn);
 257                ret = CMDSN_NORMAL_OPERATION;
 258
 259        } else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
 260                pr_debug("Received CmdSN: 0x%08x is greater"
 261                      " than ExpCmdSN: 0x%08x, not acknowledging.\n",
 262                      cmdsn, sess->exp_cmd_sn);
 263                ret = CMDSN_HIGHER_THAN_EXP;
 264
 265        } else {
 266                pr_err("Received CmdSN: 0x%08x is less than"
 267                       " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
 268                       sess->exp_cmd_sn);
 269                ret = CMDSN_LOWER_THAN_EXP;
 270        }
 271
 272        return ret;
 273}
 274
 275/*
 276 * Commands may be received out of order if MC/S is in use.
 277 * Ensure they are executed in CmdSN order.
 278 */
 279int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 280                        unsigned char *buf, __be32 cmdsn)
 281{
 282        int ret, cmdsn_ret;
 283        bool reject = false;
 284        u8 reason = ISCSI_REASON_BOOKMARK_NO_RESOURCES;
 285
 286        mutex_lock(&conn->sess->cmdsn_mutex);
 287
 288        cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
 289        switch (cmdsn_ret) {
 290        case CMDSN_NORMAL_OPERATION:
 291                ret = iscsit_execute_cmd(cmd, 0);
 292                if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 293                        iscsit_execute_ooo_cmdsns(conn->sess);
 294                else if (ret < 0) {
 295                        reject = true;
 296                        ret = CMDSN_ERROR_CANNOT_RECOVER;
 297                }
 298                break;
 299        case CMDSN_HIGHER_THAN_EXP:
 300                ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
 301                if (ret < 0) {
 302                        reject = true;
 303                        ret = CMDSN_ERROR_CANNOT_RECOVER;
 304                        break;
 305                }
 306                ret = CMDSN_HIGHER_THAN_EXP;
 307                break;
 308        case CMDSN_LOWER_THAN_EXP:
 309        case CMDSN_MAXCMDSN_OVERRUN:
 310        default:
 311                cmd->i_state = ISTATE_REMOVE;
 312                iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
 313                /*
 314                 * Existing callers for iscsit_sequence_cmd() will silently
 315                 * ignore commands with CMDSN_LOWER_THAN_EXP, so force this
 316                 * return for CMDSN_MAXCMDSN_OVERRUN as well..
 317                 */
 318                ret = CMDSN_LOWER_THAN_EXP;
 319                break;
 320        }
 321        mutex_unlock(&conn->sess->cmdsn_mutex);
 322
 323        if (reject)
 324                iscsit_reject_cmd(cmd, reason, buf);
 325
 326        return ret;
 327}
 328EXPORT_SYMBOL(iscsit_sequence_cmd);
 329
 330int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
 331{
 332        struct iscsi_conn *conn = cmd->conn;
 333        struct se_cmd *se_cmd = &cmd->se_cmd;
 334        struct iscsi_data *hdr = (struct iscsi_data *) buf;
 335        u32 payload_length = ntoh24(hdr->dlength);
 336
 337        if (conn->sess->sess_ops->InitialR2T) {
 338                pr_err("Received unexpected unsolicited data"
 339                        " while InitialR2T=Yes, protocol error.\n");
 340                transport_send_check_condition_and_sense(se_cmd,
 341                                TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
 342                return -1;
 343        }
 344
 345        if ((cmd->first_burst_len + payload_length) >
 346             conn->sess->sess_ops->FirstBurstLength) {
 347                pr_err("Total %u bytes exceeds FirstBurstLength: %u"
 348                        " for this Unsolicited DataOut Burst.\n",
 349                        (cmd->first_burst_len + payload_length),
 350                                conn->sess->sess_ops->FirstBurstLength);
 351                transport_send_check_condition_and_sense(se_cmd,
 352                                TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 353                return -1;
 354        }
 355
 356        if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
 357                return 0;
 358
 359        if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
 360            ((cmd->first_burst_len + payload_length) !=
 361              conn->sess->sess_ops->FirstBurstLength)) {
 362                pr_err("Unsolicited non-immediate data received %u"
 363                        " does not equal FirstBurstLength: %u, and does"
 364                        " not equal ExpXferLen %u.\n",
 365                        (cmd->first_burst_len + payload_length),
 366                        conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
 367                transport_send_check_condition_and_sense(se_cmd,
 368                                TCM_INCORRECT_AMOUNT_OF_DATA, 0);
 369                return -1;
 370        }
 371        return 0;
 372}
 373
 374struct iscsi_cmd *iscsit_find_cmd_from_itt(
 375        struct iscsi_conn *conn,
 376        itt_t init_task_tag)
 377{
 378        struct iscsi_cmd *cmd;
 379
 380        spin_lock_bh(&conn->cmd_lock);
 381        list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 382                if (cmd->init_task_tag == init_task_tag) {
 383                        spin_unlock_bh(&conn->cmd_lock);
 384                        return cmd;
 385                }
 386        }
 387        spin_unlock_bh(&conn->cmd_lock);
 388
 389        pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
 390                        init_task_tag, conn->cid);
 391        return NULL;
 392}
 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->init_task_tag == init_task_tag) {
 404                        spin_unlock_bh(&conn->cmd_lock);
 405                        return cmd;
 406                }
 407        }
 408        spin_unlock_bh(&conn->cmd_lock);
 409
 410        pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
 411                        " dumping payload\n", init_task_tag, conn->cid);
 412        if (length)
 413                iscsit_dump_data_payload(conn, length, 1);
 414
 415        return NULL;
 416}
 417
 418struct iscsi_cmd *iscsit_find_cmd_from_ttt(
 419        struct iscsi_conn *conn,
 420        u32 targ_xfer_tag)
 421{
 422        struct iscsi_cmd *cmd = NULL;
 423
 424        spin_lock_bh(&conn->cmd_lock);
 425        list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
 426                if (cmd->targ_xfer_tag == targ_xfer_tag) {
 427                        spin_unlock_bh(&conn->cmd_lock);
 428                        return cmd;
 429                }
 430        }
 431        spin_unlock_bh(&conn->cmd_lock);
 432
 433        pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
 434                        targ_xfer_tag, conn->cid);
 435        return NULL;
 436}
 437
 438int iscsit_find_cmd_for_recovery(
 439        struct iscsi_session *sess,
 440        struct iscsi_cmd **cmd_ptr,
 441        struct iscsi_conn_recovery **cr_ptr,
 442        itt_t init_task_tag)
 443{
 444        struct iscsi_cmd *cmd = NULL;
 445        struct iscsi_conn_recovery *cr;
 446        /*
 447         * Scan through the inactive connection recovery list's command list.
 448         * If init_task_tag matches the command is still alligent.
 449         */
 450        spin_lock(&sess->cr_i_lock);
 451        list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
 452                spin_lock(&cr->conn_recovery_cmd_lock);
 453                list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 454                        if (cmd->init_task_tag == init_task_tag) {
 455                                spin_unlock(&cr->conn_recovery_cmd_lock);
 456                                spin_unlock(&sess->cr_i_lock);
 457
 458                                *cr_ptr = cr;
 459                                *cmd_ptr = cmd;
 460                                return -2;
 461                        }
 462                }
 463                spin_unlock(&cr->conn_recovery_cmd_lock);
 464        }
 465        spin_unlock(&sess->cr_i_lock);
 466        /*
 467         * Scan through the active connection recovery list's command list.
 468         * If init_task_tag matches the command is ready to be reassigned.
 469         */
 470        spin_lock(&sess->cr_a_lock);
 471        list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
 472                spin_lock(&cr->conn_recovery_cmd_lock);
 473                list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
 474                        if (cmd->init_task_tag == init_task_tag) {
 475                                spin_unlock(&cr->conn_recovery_cmd_lock);
 476                                spin_unlock(&sess->cr_a_lock);
 477
 478                                *cr_ptr = cr;
 479                                *cmd_ptr = cmd;
 480                                return 0;
 481                        }
 482                }
 483                spin_unlock(&cr->conn_recovery_cmd_lock);
 484        }
 485        spin_unlock(&sess->cr_a_lock);
 486
 487        return -1;
 488}
 489
 490void iscsit_add_cmd_to_immediate_queue(
 491        struct iscsi_cmd *cmd,
 492        struct iscsi_conn *conn,
 493        u8 state)
 494{
 495        struct iscsi_queue_req *qr;
 496
 497        qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 498        if (!qr) {
 499                pr_err("Unable to allocate memory for"
 500                                " struct iscsi_queue_req\n");
 501                return;
 502        }
 503        INIT_LIST_HEAD(&qr->qr_list);
 504        qr->cmd = cmd;
 505        qr->state = state;
 506
 507        spin_lock_bh(&conn->immed_queue_lock);
 508        list_add_tail(&qr->qr_list, &conn->immed_queue_list);
 509        atomic_inc(&cmd->immed_queue_count);
 510        atomic_set(&conn->check_immediate_queue, 1);
 511        spin_unlock_bh(&conn->immed_queue_lock);
 512
 513        wake_up(&conn->queues_wq);
 514}
 515
 516struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
 517{
 518        struct iscsi_queue_req *qr;
 519
 520        spin_lock_bh(&conn->immed_queue_lock);
 521        if (list_empty(&conn->immed_queue_list)) {
 522                spin_unlock_bh(&conn->immed_queue_lock);
 523                return NULL;
 524        }
 525        qr = list_first_entry(&conn->immed_queue_list,
 526                              struct iscsi_queue_req, qr_list);
 527
 528        list_del(&qr->qr_list);
 529        if (qr->cmd)
 530                atomic_dec(&qr->cmd->immed_queue_count);
 531        spin_unlock_bh(&conn->immed_queue_lock);
 532
 533        return qr;
 534}
 535
 536static void iscsit_remove_cmd_from_immediate_queue(
 537        struct iscsi_cmd *cmd,
 538        struct iscsi_conn *conn)
 539{
 540        struct iscsi_queue_req *qr, *qr_tmp;
 541
 542        spin_lock_bh(&conn->immed_queue_lock);
 543        if (!atomic_read(&cmd->immed_queue_count)) {
 544                spin_unlock_bh(&conn->immed_queue_lock);
 545                return;
 546        }
 547
 548        list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 549                if (qr->cmd != cmd)
 550                        continue;
 551
 552                atomic_dec(&qr->cmd->immed_queue_count);
 553                list_del(&qr->qr_list);
 554                kmem_cache_free(lio_qr_cache, qr);
 555        }
 556        spin_unlock_bh(&conn->immed_queue_lock);
 557
 558        if (atomic_read(&cmd->immed_queue_count)) {
 559                pr_err("ITT: 0x%08x immed_queue_count: %d\n",
 560                        cmd->init_task_tag,
 561                        atomic_read(&cmd->immed_queue_count));
 562        }
 563}
 564
 565void iscsit_add_cmd_to_response_queue(
 566        struct iscsi_cmd *cmd,
 567        struct iscsi_conn *conn,
 568        u8 state)
 569{
 570        struct iscsi_queue_req *qr;
 571
 572        qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
 573        if (!qr) {
 574                pr_err("Unable to allocate memory for"
 575                        " struct iscsi_queue_req\n");
 576                return;
 577        }
 578        INIT_LIST_HEAD(&qr->qr_list);
 579        qr->cmd = cmd;
 580        qr->state = state;
 581
 582        spin_lock_bh(&conn->response_queue_lock);
 583        list_add_tail(&qr->qr_list, &conn->response_queue_list);
 584        atomic_inc(&cmd->response_queue_count);
 585        spin_unlock_bh(&conn->response_queue_lock);
 586
 587        wake_up(&conn->queues_wq);
 588}
 589
 590struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
 591{
 592        struct iscsi_queue_req *qr;
 593
 594        spin_lock_bh(&conn->response_queue_lock);
 595        if (list_empty(&conn->response_queue_list)) {
 596                spin_unlock_bh(&conn->response_queue_lock);
 597                return NULL;
 598        }
 599
 600        qr = list_first_entry(&conn->response_queue_list,
 601                              struct iscsi_queue_req, qr_list);
 602
 603        list_del(&qr->qr_list);
 604        if (qr->cmd)
 605                atomic_dec(&qr->cmd->response_queue_count);
 606        spin_unlock_bh(&conn->response_queue_lock);
 607
 608        return qr;
 609}
 610
 611static void iscsit_remove_cmd_from_response_queue(
 612        struct iscsi_cmd *cmd,
 613        struct iscsi_conn *conn)
 614{
 615        struct iscsi_queue_req *qr, *qr_tmp;
 616
 617        spin_lock_bh(&conn->response_queue_lock);
 618        if (!atomic_read(&cmd->response_queue_count)) {
 619                spin_unlock_bh(&conn->response_queue_lock);
 620                return;
 621        }
 622
 623        list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 624                                qr_list) {
 625                if (qr->cmd != cmd)
 626                        continue;
 627
 628                atomic_dec(&qr->cmd->response_queue_count);
 629                list_del(&qr->qr_list);
 630                kmem_cache_free(lio_qr_cache, qr);
 631        }
 632        spin_unlock_bh(&conn->response_queue_lock);
 633
 634        if (atomic_read(&cmd->response_queue_count)) {
 635                pr_err("ITT: 0x%08x response_queue_count: %d\n",
 636                        cmd->init_task_tag,
 637                        atomic_read(&cmd->response_queue_count));
 638        }
 639}
 640
 641bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
 642{
 643        bool empty;
 644
 645        spin_lock_bh(&conn->immed_queue_lock);
 646        empty = list_empty(&conn->immed_queue_list);
 647        spin_unlock_bh(&conn->immed_queue_lock);
 648
 649        if (!empty)
 650                return empty;
 651
 652        spin_lock_bh(&conn->response_queue_lock);
 653        empty = list_empty(&conn->response_queue_list);
 654        spin_unlock_bh(&conn->response_queue_lock);
 655
 656        return empty;
 657}
 658
 659void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
 660{
 661        struct iscsi_queue_req *qr, *qr_tmp;
 662
 663        spin_lock_bh(&conn->immed_queue_lock);
 664        list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
 665                list_del(&qr->qr_list);
 666                if (qr->cmd)
 667                        atomic_dec(&qr->cmd->immed_queue_count);
 668
 669                kmem_cache_free(lio_qr_cache, qr);
 670        }
 671        spin_unlock_bh(&conn->immed_queue_lock);
 672
 673        spin_lock_bh(&conn->response_queue_lock);
 674        list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
 675                        qr_list) {
 676                list_del(&qr->qr_list);
 677                if (qr->cmd)
 678                        atomic_dec(&qr->cmd->response_queue_count);
 679
 680                kmem_cache_free(lio_qr_cache, qr);
 681        }
 682        spin_unlock_bh(&conn->response_queue_lock);
 683}
 684
 685void iscsit_release_cmd(struct iscsi_cmd *cmd)
 686{
 687        struct iscsi_session *sess;
 688        struct se_cmd *se_cmd = &cmd->se_cmd;
 689
 690        if (cmd->conn)
 691                sess = cmd->conn->sess;
 692        else
 693                sess = cmd->sess;
 694
 695        BUG_ON(!sess || !sess->se_sess);
 696
 697        kfree(cmd->buf_ptr);
 698        kfree(cmd->pdu_list);
 699        kfree(cmd->seq_list);
 700        kfree(cmd->tmr_req);
 701        kfree(cmd->iov_data);
 702        kfree(cmd->text_in_ptr);
 703
 704        percpu_ida_free(&sess->se_sess->sess_tag_pool, se_cmd->map_tag);
 705}
 706EXPORT_SYMBOL(iscsit_release_cmd);
 707
 708void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool scsi_cmd,
 709                       bool check_queues)
 710{
 711        struct iscsi_conn *conn = cmd->conn;
 712
 713        if (scsi_cmd) {
 714                if (cmd->data_direction == DMA_TO_DEVICE) {
 715                        iscsit_stop_dataout_timer(cmd);
 716                        iscsit_free_r2ts_from_list(cmd);
 717                }
 718                if (cmd->data_direction == DMA_FROM_DEVICE)
 719                        iscsit_free_all_datain_reqs(cmd);
 720        }
 721
 722        if (conn && check_queues) {
 723                iscsit_remove_cmd_from_immediate_queue(cmd, conn);
 724                iscsit_remove_cmd_from_response_queue(cmd, conn);
 725        }
 726}
 727
 728void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
 729{
 730        struct se_cmd *se_cmd = NULL;
 731        int rc;
 732        /*
 733         * Determine if a struct se_cmd is associated with
 734         * this struct iscsi_cmd.
 735         */
 736        switch (cmd->iscsi_opcode) {
 737        case ISCSI_OP_SCSI_CMD:
 738                se_cmd = &cmd->se_cmd;
 739                __iscsit_free_cmd(cmd, true, shutdown);
 740                /*
 741                 * Fallthrough
 742                 */
 743        case ISCSI_OP_SCSI_TMFUNC:
 744                rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 745                if (!rc && shutdown && se_cmd && se_cmd->se_sess) {
 746                        __iscsit_free_cmd(cmd, true, shutdown);
 747                        target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 748                }
 749                break;
 750        case ISCSI_OP_REJECT:
 751                /*
 752                 * Handle special case for REJECT when iscsi_add_reject*() has
 753                 * overwritten the original iscsi_opcode assignment, and the
 754                 * associated cmd->se_cmd needs to be released.
 755                 */
 756                if (cmd->se_cmd.se_tfo != NULL) {
 757                        se_cmd = &cmd->se_cmd;
 758                        __iscsit_free_cmd(cmd, true, shutdown);
 759
 760                        rc = transport_generic_free_cmd(&cmd->se_cmd, shutdown);
 761                        if (!rc && shutdown && se_cmd->se_sess) {
 762                                __iscsit_free_cmd(cmd, true, shutdown);
 763                                target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 764                        }
 765                        break;
 766                }
 767                /* Fall-through */
 768        default:
 769                __iscsit_free_cmd(cmd, false, shutdown);
 770                iscsit_release_cmd(cmd);
 771                break;
 772        }
 773}
 774
 775int iscsit_check_session_usage_count(struct iscsi_session *sess)
 776{
 777        spin_lock_bh(&sess->session_usage_lock);
 778        if (sess->session_usage_count != 0) {
 779                sess->session_waiting_on_uc = 1;
 780                spin_unlock_bh(&sess->session_usage_lock);
 781                if (in_interrupt())
 782                        return 2;
 783
 784                wait_for_completion(&sess->session_waiting_on_uc_comp);
 785                return 1;
 786        }
 787        spin_unlock_bh(&sess->session_usage_lock);
 788
 789        return 0;
 790}
 791
 792void iscsit_dec_session_usage_count(struct iscsi_session *sess)
 793{
 794        spin_lock_bh(&sess->session_usage_lock);
 795        sess->session_usage_count--;
 796
 797        if (!sess->session_usage_count && sess->session_waiting_on_uc)
 798                complete(&sess->session_waiting_on_uc_comp);
 799
 800        spin_unlock_bh(&sess->session_usage_lock);
 801}
 802
 803void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 804{
 805        spin_lock_bh(&sess->session_usage_lock);
 806        sess->session_usage_count++;
 807        spin_unlock_bh(&sess->session_usage_lock);
 808}
 809
 810/*
 811 *      Setup conn->if_marker and conn->of_marker values based upon
 812 *      the initial marker-less interval. (see iSCSI v19 A.2)
 813 */
 814int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
 815{
 816        int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
 817        /*
 818         * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
 819         */
 820        u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
 821        u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
 822
 823        if (conn->conn_ops->OFMarker) {
 824                /*
 825                 * Account for the first Login Command received not
 826                 * via iscsi_recv_msg().
 827                 */
 828                conn->of_marker += ISCSI_HDR_LEN;
 829                if (conn->of_marker <= OFMarkInt) {
 830                        conn->of_marker = (OFMarkInt - conn->of_marker);
 831                } else {
 832                        login_ofmarker_count = (conn->of_marker / OFMarkInt);
 833                        next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
 834                                        (login_ofmarker_count * MARKER_SIZE);
 835                        conn->of_marker = (next_marker - conn->of_marker);
 836                }
 837                conn->of_marker_offset = 0;
 838                pr_debug("Setting OFMarker value to %u based on Initial"
 839                        " Markerless Interval.\n", conn->of_marker);
 840        }
 841
 842        if (conn->conn_ops->IFMarker) {
 843                if (conn->if_marker <= IFMarkInt) {
 844                        conn->if_marker = (IFMarkInt - conn->if_marker);
 845                } else {
 846                        login_ifmarker_count = (conn->if_marker / IFMarkInt);
 847                        next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
 848                                        (login_ifmarker_count * MARKER_SIZE);
 849                        conn->if_marker = (next_marker - conn->if_marker);
 850                }
 851                pr_debug("Setting IFMarker value to %u based on Initial"
 852                        " Markerless Interval.\n", conn->if_marker);
 853        }
 854
 855        return 0;
 856}
 857
 858struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 859{
 860        struct iscsi_conn *conn;
 861
 862        spin_lock_bh(&sess->conn_lock);
 863        list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 864                if ((conn->cid == cid) &&
 865                    (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
 866                        iscsit_inc_conn_usage_count(conn);
 867                        spin_unlock_bh(&sess->conn_lock);
 868                        return conn;
 869                }
 870        }
 871        spin_unlock_bh(&sess->conn_lock);
 872
 873        return NULL;
 874}
 875
 876struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
 877{
 878        struct iscsi_conn *conn;
 879
 880        spin_lock_bh(&sess->conn_lock);
 881        list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
 882                if (conn->cid == cid) {
 883                        iscsit_inc_conn_usage_count(conn);
 884                        spin_lock(&conn->state_lock);
 885                        atomic_set(&conn->connection_wait_rcfr, 1);
 886                        spin_unlock(&conn->state_lock);
 887                        spin_unlock_bh(&sess->conn_lock);
 888                        return conn;
 889                }
 890        }
 891        spin_unlock_bh(&sess->conn_lock);
 892
 893        return NULL;
 894}
 895
 896void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
 897{
 898        spin_lock_bh(&conn->conn_usage_lock);
 899        if (conn->conn_usage_count != 0) {
 900                conn->conn_waiting_on_uc = 1;
 901                spin_unlock_bh(&conn->conn_usage_lock);
 902
 903                wait_for_completion(&conn->conn_waiting_on_uc_comp);
 904                return;
 905        }
 906        spin_unlock_bh(&conn->conn_usage_lock);
 907}
 908
 909void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
 910{
 911        spin_lock_bh(&conn->conn_usage_lock);
 912        conn->conn_usage_count--;
 913
 914        if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
 915                complete(&conn->conn_waiting_on_uc_comp);
 916
 917        spin_unlock_bh(&conn->conn_usage_lock);
 918}
 919
 920void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
 921{
 922        spin_lock_bh(&conn->conn_usage_lock);
 923        conn->conn_usage_count++;
 924        spin_unlock_bh(&conn->conn_usage_lock);
 925}
 926
 927static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
 928{
 929        u8 state;
 930        struct iscsi_cmd *cmd;
 931
 932        cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
 933        if (!cmd)
 934                return -1;
 935
 936        cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
 937        state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
 938                                ISTATE_SEND_NOPIN_NO_RESPONSE;
 939        cmd->init_task_tag = RESERVED_ITT;
 940        spin_lock_bh(&conn->sess->ttt_lock);
 941        cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
 942                        0xFFFFFFFF;
 943        if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
 944                cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
 945        spin_unlock_bh(&conn->sess->ttt_lock);
 946
 947        spin_lock_bh(&conn->cmd_lock);
 948        list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
 949        spin_unlock_bh(&conn->cmd_lock);
 950
 951        if (want_response)
 952                iscsit_start_nopin_response_timer(conn);
 953        iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
 954
 955        return 0;
 956}
 957
 958static void iscsit_handle_nopin_response_timeout(unsigned long data)
 959{
 960        struct iscsi_conn *conn = (struct iscsi_conn *) data;
 961
 962        iscsit_inc_conn_usage_count(conn);
 963
 964        spin_lock_bh(&conn->nopin_timer_lock);
 965        if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
 966                spin_unlock_bh(&conn->nopin_timer_lock);
 967                iscsit_dec_conn_usage_count(conn);
 968                return;
 969        }
 970
 971        pr_debug("Did not receive response to NOPIN on CID: %hu on"
 972                " SID: %u, failing connection.\n", conn->cid,
 973                        conn->sess->sid);
 974        conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
 975        spin_unlock_bh(&conn->nopin_timer_lock);
 976
 977        {
 978        struct iscsi_portal_group *tpg = conn->sess->tpg;
 979        struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
 980
 981        if (tiqn) {
 982                spin_lock_bh(&tiqn->sess_err_stats.lock);
 983                strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
 984                                conn->sess->sess_ops->InitiatorName);
 985                tiqn->sess_err_stats.last_sess_failure_type =
 986                                ISCSI_SESS_ERR_CXN_TIMEOUT;
 987                tiqn->sess_err_stats.cxn_timeout_errors++;
 988                atomic_long_inc(&conn->sess->conn_timeout_errors);
 989                spin_unlock_bh(&tiqn->sess_err_stats.lock);
 990        }
 991        }
 992
 993        iscsit_cause_connection_reinstatement(conn, 0);
 994        iscsit_dec_conn_usage_count(conn);
 995}
 996
 997void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
 998{
 999        struct iscsi_session *sess = conn->sess;
1000        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1001
1002        spin_lock_bh(&conn->nopin_timer_lock);
1003        if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1004                spin_unlock_bh(&conn->nopin_timer_lock);
1005                return;
1006        }
1007
1008        mod_timer(&conn->nopin_response_timer,
1009                (get_jiffies_64() + na->nopin_response_timeout * HZ));
1010        spin_unlock_bh(&conn->nopin_timer_lock);
1011}
1012
1013/*
1014 *      Called with conn->nopin_timer_lock held.
1015 */
1016void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
1017{
1018        struct iscsi_session *sess = conn->sess;
1019        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1020
1021        spin_lock_bh(&conn->nopin_timer_lock);
1022        if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
1023                spin_unlock_bh(&conn->nopin_timer_lock);
1024                return;
1025        }
1026
1027        init_timer(&conn->nopin_response_timer);
1028        conn->nopin_response_timer.expires =
1029                (get_jiffies_64() + na->nopin_response_timeout * HZ);
1030        conn->nopin_response_timer.data = (unsigned long)conn;
1031        conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
1032        conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
1033        conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
1034        add_timer(&conn->nopin_response_timer);
1035
1036        pr_debug("Started NOPIN Response Timer on CID: %d to %u"
1037                " seconds\n", conn->cid, na->nopin_response_timeout);
1038        spin_unlock_bh(&conn->nopin_timer_lock);
1039}
1040
1041void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
1042{
1043        spin_lock_bh(&conn->nopin_timer_lock);
1044        if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1045                spin_unlock_bh(&conn->nopin_timer_lock);
1046                return;
1047        }
1048        conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1049        spin_unlock_bh(&conn->nopin_timer_lock);
1050
1051        del_timer_sync(&conn->nopin_response_timer);
1052
1053        spin_lock_bh(&conn->nopin_timer_lock);
1054        conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1055        spin_unlock_bh(&conn->nopin_timer_lock);
1056}
1057
1058static void iscsit_handle_nopin_timeout(unsigned long data)
1059{
1060        struct iscsi_conn *conn = (struct iscsi_conn *) data;
1061
1062        iscsit_inc_conn_usage_count(conn);
1063
1064        spin_lock_bh(&conn->nopin_timer_lock);
1065        if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1066                spin_unlock_bh(&conn->nopin_timer_lock);
1067                iscsit_dec_conn_usage_count(conn);
1068                return;
1069        }
1070        conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1071        spin_unlock_bh(&conn->nopin_timer_lock);
1072
1073        iscsit_add_nopin(conn, 1);
1074        iscsit_dec_conn_usage_count(conn);
1075}
1076
1077/*
1078 * Called with conn->nopin_timer_lock held.
1079 */
1080void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1081{
1082        struct iscsi_session *sess = conn->sess;
1083        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1084        /*
1085        * NOPIN timeout is disabled.
1086         */
1087        if (!na->nopin_timeout)
1088                return;
1089
1090        if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1091                return;
1092
1093        init_timer(&conn->nopin_timer);
1094        conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1095        conn->nopin_timer.data = (unsigned long)conn;
1096        conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1097        conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1098        conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1099        add_timer(&conn->nopin_timer);
1100
1101        pr_debug("Started NOPIN Timer on CID: %d at %u second"
1102                " interval\n", conn->cid, na->nopin_timeout);
1103}
1104
1105void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1106{
1107        struct iscsi_session *sess = conn->sess;
1108        struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1109        /*
1110         * NOPIN timeout is disabled..
1111         */
1112        if (!na->nopin_timeout)
1113                return;
1114
1115        spin_lock_bh(&conn->nopin_timer_lock);
1116        if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1117                spin_unlock_bh(&conn->nopin_timer_lock);
1118                return;
1119        }
1120
1121        init_timer(&conn->nopin_timer);
1122        conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1123        conn->nopin_timer.data = (unsigned long)conn;
1124        conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1125        conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1126        conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1127        add_timer(&conn->nopin_timer);
1128
1129        pr_debug("Started NOPIN Timer on CID: %d at %u second"
1130                        " interval\n", conn->cid, na->nopin_timeout);
1131        spin_unlock_bh(&conn->nopin_timer_lock);
1132}
1133
1134void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1135{
1136        spin_lock_bh(&conn->nopin_timer_lock);
1137        if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1138                spin_unlock_bh(&conn->nopin_timer_lock);
1139                return;
1140        }
1141        conn->nopin_timer_flags |= ISCSI_TF_STOP;
1142        spin_unlock_bh(&conn->nopin_timer_lock);
1143
1144        del_timer_sync(&conn->nopin_timer);
1145
1146        spin_lock_bh(&conn->nopin_timer_lock);
1147        conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1148        spin_unlock_bh(&conn->nopin_timer_lock);
1149}
1150
1151int iscsit_send_tx_data(
1152        struct iscsi_cmd *cmd,
1153        struct iscsi_conn *conn,
1154        int use_misc)
1155{
1156        int tx_sent, tx_size;
1157        u32 iov_count;
1158        struct kvec *iov;
1159
1160send_data:
1161        tx_size = cmd->tx_size;
1162
1163        if (!use_misc) {
1164                iov = &cmd->iov_data[0];
1165                iov_count = cmd->iov_data_count;
1166        } else {
1167                iov = &cmd->iov_misc[0];
1168                iov_count = cmd->iov_misc_count;
1169        }
1170
1171        tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1172        if (tx_size != tx_sent) {
1173                if (tx_sent == -EAGAIN) {
1174                        pr_err("tx_data() returned -EAGAIN\n");
1175                        goto send_data;
1176                } else
1177                        return -1;
1178        }
1179        cmd->tx_size = 0;
1180
1181        return 0;
1182}
1183
1184int iscsit_fe_sendpage_sg(
1185        struct iscsi_cmd *cmd,
1186        struct iscsi_conn *conn)
1187{
1188        struct scatterlist *sg = cmd->first_data_sg;
1189        struct kvec iov;
1190        u32 tx_hdr_size, data_len;
1191        u32 offset = cmd->first_data_sg_off;
1192        int tx_sent, iov_off;
1193
1194send_hdr:
1195        tx_hdr_size = ISCSI_HDR_LEN;
1196        if (conn->conn_ops->HeaderDigest)
1197                tx_hdr_size += ISCSI_CRC_LEN;
1198
1199        iov.iov_base = cmd->pdu;
1200        iov.iov_len = tx_hdr_size;
1201
1202        tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1203        if (tx_hdr_size != tx_sent) {
1204                if (tx_sent == -EAGAIN) {
1205                        pr_err("tx_data() returned -EAGAIN\n");
1206                        goto send_hdr;
1207                }
1208                return -1;
1209        }
1210
1211        data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1212        /*
1213         * Set iov_off used by padding and data digest tx_data() calls below
1214         * in order to determine proper offset into cmd->iov_data[]
1215         */
1216        if (conn->conn_ops->DataDigest) {
1217                data_len -= ISCSI_CRC_LEN;
1218                if (cmd->padding)
1219                        iov_off = (cmd->iov_data_count - 2);
1220                else
1221                        iov_off = (cmd->iov_data_count - 1);
1222        } else {
1223                iov_off = (cmd->iov_data_count - 1);
1224        }
1225        /*
1226         * Perform sendpage() for each page in the scatterlist
1227         */
1228        while (data_len) {
1229                u32 space = (sg->length - offset);
1230                u32 sub_len = min_t(u32, data_len, space);
1231send_pg:
1232                tx_sent = conn->sock->ops->sendpage(conn->sock,
1233                                        sg_page(sg), sg->offset + offset, sub_len, 0);
1234                if (tx_sent != sub_len) {
1235                        if (tx_sent == -EAGAIN) {
1236                                pr_err("tcp_sendpage() returned"
1237                                                " -EAGAIN\n");
1238                                goto send_pg;
1239                        }
1240
1241                        pr_err("tcp_sendpage() failure: %d\n",
1242                                        tx_sent);
1243                        return -1;
1244                }
1245
1246                data_len -= sub_len;
1247                offset = 0;
1248                sg = sg_next(sg);
1249        }
1250
1251send_padding:
1252        if (cmd->padding) {
1253                struct kvec *iov_p = &cmd->iov_data[iov_off++];
1254
1255                tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1256                if (cmd->padding != tx_sent) {
1257                        if (tx_sent == -EAGAIN) {
1258                                pr_err("tx_data() returned -EAGAIN\n");
1259                                goto send_padding;
1260                        }
1261                        return -1;
1262                }
1263        }
1264
1265send_datacrc:
1266        if (conn->conn_ops->DataDigest) {
1267                struct kvec *iov_d = &cmd->iov_data[iov_off];
1268
1269                tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1270                if (ISCSI_CRC_LEN != tx_sent) {
1271                        if (tx_sent == -EAGAIN) {
1272                                pr_err("tx_data() returned -EAGAIN\n");
1273                                goto send_datacrc;
1274                        }
1275                        return -1;
1276                }
1277        }
1278
1279        return 0;
1280}
1281
1282/*
1283 *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1284 *      back to the Initiator when an expection condition occurs with the
1285 *      errors set in status_class and status_detail.
1286 *
1287 *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1288 *      Returns:        0 on success, -1 on error.
1289 */
1290int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1291{
1292        struct iscsi_login_rsp *hdr;
1293        struct iscsi_login *login = conn->conn_login;
1294
1295        login->login_failed = 1;
1296        iscsit_collect_login_stats(conn, status_class, status_detail);
1297
1298        memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1299
1300        hdr     = (struct iscsi_login_rsp *)&login->rsp[0];
1301        hdr->opcode             = ISCSI_OP_LOGIN_RSP;
1302        hdr->status_class       = status_class;
1303        hdr->status_detail      = status_detail;
1304        hdr->itt                = conn->login_itt;
1305
1306        return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1307}
1308
1309void iscsit_print_session_params(struct iscsi_session *sess)
1310{
1311        struct iscsi_conn *conn;
1312
1313        pr_debug("-----------------------------[Session Params for"
1314                " SID: %u]-----------------------------\n", sess->sid);
1315        spin_lock_bh(&sess->conn_lock);
1316        list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1317                iscsi_dump_conn_ops(conn->conn_ops);
1318        spin_unlock_bh(&sess->conn_lock);
1319
1320        iscsi_dump_sess_ops(sess->sess_ops);
1321}
1322
1323static int iscsit_do_rx_data(
1324        struct iscsi_conn *conn,
1325        struct iscsi_data_count *count)
1326{
1327        int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
1328        struct kvec *iov_p;
1329        struct msghdr msg;
1330
1331        if (!conn || !conn->sock || !conn->conn_ops)
1332                return -1;
1333
1334        memset(&msg, 0, sizeof(struct msghdr));
1335
1336        iov_p = count->iov;
1337        iov_len = count->iov_count;
1338
1339        while (total_rx < data) {
1340                rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
1341                                        (data - total_rx), MSG_WAITALL);
1342                if (rx_loop <= 0) {
1343                        pr_debug("rx_loop: %d total_rx: %d\n",
1344                                rx_loop, total_rx);
1345                        return rx_loop;
1346                }
1347                total_rx += rx_loop;
1348                pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1349                                rx_loop, total_rx, data);
1350        }
1351
1352        return total_rx;
1353}
1354
1355static int iscsit_do_tx_data(
1356        struct iscsi_conn *conn,
1357        struct iscsi_data_count *count)
1358{
1359        int data = count->data_length, total_tx = 0, tx_loop = 0, iov_len;
1360        struct kvec *iov_p;
1361        struct msghdr msg;
1362
1363        if (!conn || !conn->sock || !conn->conn_ops)
1364                return -1;
1365
1366        if (data <= 0) {
1367                pr_err("Data length is: %d\n", data);
1368                return -1;
1369        }
1370
1371        memset(&msg, 0, sizeof(struct msghdr));
1372
1373        iov_p = count->iov;
1374        iov_len = count->iov_count;
1375
1376        while (total_tx < data) {
1377                tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1378                                        (data - total_tx));
1379                if (tx_loop <= 0) {
1380                        pr_debug("tx_loop: %d total_tx %d\n",
1381                                tx_loop, total_tx);
1382                        return tx_loop;
1383                }
1384                total_tx += tx_loop;
1385                pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1386                                        tx_loop, total_tx, data);
1387        }
1388
1389        return total_tx;
1390}
1391
1392int rx_data(
1393        struct iscsi_conn *conn,
1394        struct kvec *iov,
1395        int iov_count,
1396        int data)
1397{
1398        struct iscsi_data_count c;
1399
1400        if (!conn || !conn->sock || !conn->conn_ops)
1401                return -1;
1402
1403        memset(&c, 0, sizeof(struct iscsi_data_count));
1404        c.iov = iov;
1405        c.iov_count = iov_count;
1406        c.data_length = data;
1407        c.type = ISCSI_RX_DATA;
1408
1409        return iscsit_do_rx_data(conn, &c);
1410}
1411
1412int tx_data(
1413        struct iscsi_conn *conn,
1414        struct kvec *iov,
1415        int iov_count,
1416        int data)
1417{
1418        struct iscsi_data_count c;
1419
1420        if (!conn || !conn->sock || !conn->conn_ops)
1421                return -1;
1422
1423        memset(&c, 0, sizeof(struct iscsi_data_count));
1424        c.iov = iov;
1425        c.iov_count = iov_count;
1426        c.data_length = data;
1427        c.type = ISCSI_TX_DATA;
1428
1429        return iscsit_do_tx_data(conn, &c);
1430}
1431
1432void iscsit_collect_login_stats(
1433        struct iscsi_conn *conn,
1434        u8 status_class,
1435        u8 status_detail)
1436{
1437        struct iscsi_param *intrname = NULL;
1438        struct iscsi_tiqn *tiqn;
1439        struct iscsi_login_stats *ls;
1440
1441        tiqn = iscsit_snmp_get_tiqn(conn);
1442        if (!tiqn)
1443                return;
1444
1445        ls = &tiqn->login_stats;
1446
1447        spin_lock(&ls->lock);
1448        if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1449            ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1450                /* We already have the failure info for this login */
1451                spin_unlock(&ls->lock);
1452                return;
1453        }
1454
1455        if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1456                ls->accepts++;
1457        else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1458                ls->redirects++;
1459                ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1460        } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1461                 (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1462                ls->authenticate_fails++;
1463                ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1464        } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1465                 (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1466                ls->authorize_fails++;
1467                ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1468        } else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1469                 (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1470                ls->negotiate_fails++;
1471                ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1472        } else {
1473                ls->other_fails++;
1474                ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1475        }
1476
1477        /* Save initiator name, ip address and time, if it is a failed login */
1478        if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1479                if (conn->param_list)
1480                        intrname = iscsi_find_param_from_key(INITIATORNAME,
1481                                                             conn->param_list);
1482                strcpy(ls->last_intr_fail_name,
1483                       (intrname ? intrname->value : "Unknown"));
1484
1485                ls->last_intr_fail_ip_family = conn->login_family;
1486
1487                snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1488                                "%s", conn->login_ip);
1489                ls->last_fail_time = get_jiffies_64();
1490        }
1491
1492        spin_unlock(&ls->lock);
1493}
1494
1495struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1496{
1497        struct iscsi_portal_group *tpg;
1498
1499        if (!conn || !conn->sess)
1500                return NULL;
1501
1502        tpg = conn->sess->tpg;
1503        if (!tpg)
1504                return NULL;
1505
1506        if (!tpg->tpg_tiqn)
1507                return NULL;
1508
1509        return tpg->tpg_tiqn;
1510}
1511