drivers/scsi/libiscsi.c

   1 /*
   2  * iSCSI lib functions
   3  *
   4  * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
   5  * Copyright (C) 2004 - 2006 Mike Christie
   6  * Copyright (C) 2004 - 2005 Dmitry Yusupov
   7  * Copyright (C) 2004 - 2005 Alex Aizman
   8  * maintained by open-iscsi@googlegroups.com
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  */
  24 #include <linux/types.h>
  25 #include <linux/kfifo.h>
  26 #include <linux/delay.h>
  27 #include <linux/log2.h>
  28 #include <linux/slab.h>
  29 #include <linux/module.h>
  30 #include <asm/unaligned.h>
  31 #include <net/tcp.h>
  32 #include <scsi/scsi_cmnd.h>
  33 #include <scsi/scsi_device.h>
  34 #include <scsi/scsi_eh.h>
  35 #include <scsi/scsi_tcq.h>
  36 #include <scsi/scsi_host.h>
  37 #include <scsi/scsi.h>
  38 #include <scsi/iscsi_proto.h>
  39 #include <scsi/scsi_transport.h>
  40 #include <scsi/scsi_transport_iscsi.h>
  41 #include <scsi/libiscsi.h>
  42
  43 static int iscsi_dbg_lib_conn;
  44 module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
  45                    S_IRUGO | S_IWUSR);
  46 MODULE_PARM_DESC(debug_libiscsi_conn,
  47                  "Turn on debugging for connections in libiscsi module. "
  48                  "Set to 1 to turn on, and zero to turn off. Default is off.");
  49
  50 static int iscsi_dbg_lib_session;
  51 module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
  52                    S_IRUGO | S_IWUSR);
  53 MODULE_PARM_DESC(debug_libiscsi_session,
  54                  "Turn on debugging for sessions in libiscsi module. "
  55                  "Set to 1 to turn on, and zero to turn off. Default is off.");
  56
  57 static int iscsi_dbg_lib_eh;
  58 module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
  59                    S_IRUGO | S_IWUSR);
  60 MODULE_PARM_DESC(debug_libiscsi_eh,
  61                  "Turn on debugging for error handling in libiscsi module. "
  62                  "Set to 1 to turn on, and zero to turn off. Default is off.");
  63
  64 #define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...)                  \
  65         do {                                                    \
  66                 if (iscsi_dbg_lib_conn)                         \
  67                         iscsi_conn_printk(KERN_INFO, _conn,     \
  68                                              "%s " dbg_fmt,     \
  69                                              __func__, ##arg);  \
  70         } while (0);
  71
  72 #define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...)                    \
  73         do {                                                            \
  74                 if (iscsi_dbg_lib_session)                              \
  75                         iscsi_session_printk(KERN_INFO, _session,       \
  76                                              "%s " dbg_fmt,             \
  77                                              __func__, ##arg);          \
  78         } while (0);
  79
  80 #define ISCSI_DBG_EH(_session, dbg_fmt, arg...)                         \
  81         do {                                                            \
  82                 if (iscsi_dbg_lib_eh)                                   \
  83                         iscsi_session_printk(KERN_INFO, _session,       \
  84                                              "%s " dbg_fmt,             \
  85                                              __func__, ##arg);          \
  86         } while (0);
  87
  88 inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
  89 {
  90         struct Scsi_Host *shost = conn->session->host;
  91         struct iscsi_host *ihost = shost_priv(shost);
  92
  93         if (ihost->workq)
  94                 queue_work(ihost->workq, &conn->xmitwork);
  95 }
  96 EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
  97
  98 static void __iscsi_update_cmdsn(struct iscsi_session *session,
  99                                  uint32_t exp_cmdsn, uint32_t max_cmdsn)
 100 {
 101         /*
 102          * standard specifies this check for when to update expected and
 103          * max sequence numbers
 104          */
 105         if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
 106                 return;
 107
 108         if (exp_cmdsn != session->exp_cmdsn &&
 109             !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
 110                 session->exp_cmdsn = exp_cmdsn;
 111
 112         if (max_cmdsn != session->max_cmdsn &&
 113             !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
 114                 session->max_cmdsn = max_cmdsn;
 115                 /*
 116                  * if the window closed with IO queued, then kick the
 117                  * xmit thread
 118                  */
 119                 if (!list_empty(&session->leadconn->cmdqueue) ||
 120                     !list_empty(&session->leadconn->mgmtqueue))
 121                         iscsi_conn_queue_work(session->leadconn);
 122         }
 123 }
 124
 125 void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
 126 {
 127         __iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
 128                              be32_to_cpu(hdr->max_cmdsn));
 129 }
 130 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
 131
 132 /**
 133  * iscsi_prep_data_out_pdu - initialize Data-Out
 134  * @task: scsi command task
 135  * @r2t: R2T info
 136  * @hdr: iscsi data in pdu
 137  *
 138  * Notes:
 139  *      Initialize Data-Out within this R2T sequence and finds
 140  *      proper data_offset within this SCSI command.
 141  *
 142  *      This function is called with connection lock taken.
 143  **/
 144 void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
 145                            struct iscsi_data *hdr)
 146 {
 147         struct iscsi_conn *conn = task->conn;
 148         unsigned int left = r2t->data_length - r2t->sent;
 149
 150         task->hdr_len = sizeof(struct iscsi_data);
 151
 152         memset(hdr, 0, sizeof(struct iscsi_data));
 153         hdr->ttt = r2t->ttt;
 154         hdr->datasn = cpu_to_be32(r2t->datasn);
 155         r2t->datasn++;
 156         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
 157         hdr->lun = task->lun;
 158         hdr->itt = task->hdr_itt;
 159         hdr->exp_statsn = r2t->exp_statsn;
 160         hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
 161         if (left > conn->max_xmit_dlength) {
 162                 hton24(hdr->dlength, conn->max_xmit_dlength);
 163                 r2t->data_count = conn->max_xmit_dlength;
 164                 hdr->flags = 0;
 165         } else {
 166                 hton24(hdr->dlength, left);
 167                 r2t->data_count = left;
 168                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
 169         }
 170         conn->dataout_pdus_cnt++;
 171 }
 172 EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
 173
 174 static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
 175 {
 176         unsigned exp_len = task->hdr_len + len;
 177
 178         if (exp_len > task->hdr_max) {
 179                 WARN_ON(1);
 180                 return -EINVAL;
 181         }
 182
 183         WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
 184         task->hdr_len = exp_len;
 185         return 0;
 186 }
 187
 188 /*
 189  * make an extended cdb AHS
 190  */
 191 static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
 192 {
 193         struct scsi_cmnd *cmd = task->sc;
 194         unsigned rlen, pad_len;
 195         unsigned short ahslength;
 196         struct iscsi_ecdb_ahdr *ecdb_ahdr;
 197         int rc;
 198
 199         ecdb_ahdr = iscsi_next_hdr(task);
 200         rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
 201
 202         BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
 203         ahslength = rlen + sizeof(ecdb_ahdr->reserved);
 204
 205         pad_len = iscsi_padding(rlen);
 206
 207         rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
 208                            sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
 209         if (rc)
 210                 return rc;
 211
 212         if (pad_len)
 213                 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
 214
 215         ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
 216         ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
 217         ecdb_ahdr->reserved = 0;
 218         memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
 219
 220         ISCSI_DBG_SESSION(task->conn->session,
 221                           "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
 222                           "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
 223                           "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
 224                           task->hdr_len);
 225         return 0;
 226 }
 227
 228 static int iscsi_prep_bidi_ahs(struct iscsi_task *task)
 229 {
 230         struct scsi_cmnd *sc = task->sc;
 231         struct iscsi_rlength_ahdr *rlen_ahdr;
 232         int rc;
 233
 234         rlen_ahdr = iscsi_next_hdr(task);
 235         rc = iscsi_add_hdr(task, sizeof(*rlen_ahdr));
 236         if (rc)
 237                 return rc;
 238
 239         rlen_ahdr->ahslength =
 240                 cpu_to_be16(sizeof(rlen_ahdr->read_length) +
 241                                                   sizeof(rlen_ahdr->reserved));
 242         rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
 243         rlen_ahdr->reserved = 0;
 244         rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
 245
 246         ISCSI_DBG_SESSION(task->conn->session,
 247                           "bidi-in rlen_ahdr->read_length(%d) "
 248                           "rlen_ahdr->ahslength(%d)\n",
 249                           be32_to_cpu(rlen_ahdr->read_length),
 250                           be16_to_cpu(rlen_ahdr->ahslength));
 251         return 0;
 252 }
 253
 254 /**
 255  * iscsi_check_tmf_restrictions - check if a task is affected by TMF
 256  * @task: iscsi task
 257  * @opcode: opcode to check for
 258  *
 259  * During TMF a task has to be checked if it's affected.
 260  * All unrelated I/O can be passed through, but I/O to the
 261  * affected LUN should be restricted.
 262  * If 'fast_abort' is set we won't be sending any I/O to the
 263  * affected LUN.
 264  * Otherwise the target is waiting for all TTTs to be completed,
 265  * so we have to send all outstanding Data-Out PDUs to the target.
 266  */
 267 static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
 268 {
 269         struct iscsi_conn *conn = task->conn;
 270         struct iscsi_tm *tmf = &conn->tmhdr;
 271         unsigned int hdr_lun;
 272
 273         if (conn->tmf_state == TMF_INITIAL)
 274                 return 0;
 275
 276         if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
 277                 return 0;
 278
 279         switch (ISCSI_TM_FUNC_VALUE(tmf)) {
 280         case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
 281                 /*
 282                  * Allow PDUs for unrelated LUNs
 283                  */
 284                 hdr_lun = scsilun_to_int(&tmf->lun);
 285                 if (hdr_lun != task->sc->device->lun)
 286                         return 0;
 287                 /* fall through */
 288         case ISCSI_TM_FUNC_TARGET_WARM_RESET:
 289                 /*
 290                  * Fail all SCSI cmd PDUs
 291                  */
 292                 if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
 293                         iscsi_conn_printk(KERN_INFO, conn,
 294                                           "task [op %x/%x itt "
 295                                           "0x%x/0x%x] "
 296                                           "rejected.\n",
 297                                           task->hdr->opcode, opcode,
 298                                           task->itt, task->hdr_itt);
 299                         return -EACCES;
 300                 }
 301                 /*
 302                  * And also all data-out PDUs in response to R2T
 303                  * if fast_abort is set.
 304                  */
 305                 if (conn->session->fast_abort) {
 306                         iscsi_conn_printk(KERN_INFO, conn,
 307                                           "task [op %x/%x itt "
 308                                           "0x%x/0x%x] fast abort.\n",
 309                                           task->hdr->opcode, opcode,
 310                                           task->itt, task->hdr_itt);
 311                         return -EACCES;
 312                 }
 313                 break;
 314         case ISCSI_TM_FUNC_ABORT_TASK:
 315                 /*
 316                  * the caller has already checked if the task
 317                  * they want to abort was in the pending queue so if
 318                  * we are here the cmd pdu has gone out already, and
 319                  * we will only hit this for data-outs
 320                  */
 321                 if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
 322                     task->hdr_itt == tmf->rtt) {
 323                         ISCSI_DBG_SESSION(conn->session,
 324                                           "Preventing task %x/%x from sending "
 325                                           "data-out due to abort task in "
 326                                           "progress\n", task->itt,
 327                                           task->hdr_itt);
 328                         return -EACCES;
 329                 }
 330                 break;
 331         }
 332
 333         return 0;
 334 }
 335
 336 /**
 337  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 338  * @task: iscsi task
 339  *
 340  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 341  * fields like dlength or final based on how much data it sends
 342  */
 343 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
 344 {
 345         struct iscsi_conn *conn = task->conn;
 346         struct iscsi_session *session = conn->session;
 347         struct scsi_cmnd *sc = task->sc;
 348         struct iscsi_scsi_req *hdr;
 349         unsigned hdrlength, cmd_len;
 350         itt_t itt;
 351         int rc;
 352
 353         rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
 354         if (rc)
 355                 return rc;
 356
 357         if (conn->session->tt->alloc_pdu) {
 358                 rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
 359                 if (rc)
 360                         return rc;
 361         }
 362         hdr = (struct iscsi_scsi_req *)task->hdr;
 363         itt = hdr->itt;
 364         memset(hdr, 0, sizeof(*hdr));
 365
 366         if (session->tt->parse_pdu_itt)
 367                 hdr->itt = task->hdr_itt = itt;
 368         else
 369                 hdr->itt = task->hdr_itt = build_itt(task->itt,
 370                                                      task->conn->session->age);
 371         task->hdr_len = 0;
 372         rc = iscsi_add_hdr(task, sizeof(*hdr));
 373         if (rc)
 374                 return rc;
 375         hdr->opcode = ISCSI_OP_SCSI_CMD;
 376         hdr->flags = ISCSI_ATTR_SIMPLE;
 377         int_to_scsilun(sc->device->lun, &hdr->lun);
 378         task->lun = hdr->lun;
 379         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 380         cmd_len = sc->cmd_len;
 381         if (cmd_len < ISCSI_CDB_SIZE)
 382                 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
 383         else if (cmd_len > ISCSI_CDB_SIZE) {
 384                 rc = iscsi_prep_ecdb_ahs(task);
 385                 if (rc)
 386                         return rc;
 387                 cmd_len = ISCSI_CDB_SIZE;
 388         }
 389         memcpy(hdr->cdb, sc->cmnd, cmd_len);
 390
 391         task->imm_count = 0;
 392         if (scsi_bidi_cmnd(sc)) {
 393                 hdr->flags |= ISCSI_FLAG_CMD_READ;
 394                 rc = iscsi_prep_bidi_ahs(task);
 395                 if (rc)
 396                         return rc;
 397         }
 398         if (sc->sc_data_direction == DMA_TO_DEVICE) {
 399                 unsigned out_len = scsi_out(sc)->length;
 400                 struct iscsi_r2t_info *r2t = &task->unsol_r2t;
 401
 402                 hdr->data_length = cpu_to_be32(out_len);
 403                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 404                 /*
 405                  * Write counters:
 406                  *
 407                  *      imm_count       bytes to be sent right after
 408                  *                      SCSI PDU Header
 409                  *
 410                  *      unsol_count     bytes(as Data-Out) to be sent
 411                  *                      without R2T ack right after
 412                  *                      immediate data
 413                  *
 414                  *      r2t data_length bytes to be sent via R2T ack's
 415                  *
 416                  *      pad_count       bytes to be sent as zero-padding
 417                  */
 418                 memset(r2t, 0, sizeof(*r2t));
 419
 420                 if (session->imm_data_en) {
 421                         if (out_len >= session->first_burst)
 422                                 task->imm_count = min(session->first_burst,
 423                                                         conn->max_xmit_dlength);
 424                         else
 425                                 task->imm_count = min(out_len,
 426                                                         conn->max_xmit_dlength);
 427                         hton24(hdr->dlength, task->imm_count);
 428                 } else
 429                         zero_data(hdr->dlength);
 430
 431                 if (!session->initial_r2t_en) {
 432                         r2t->data_length = min(session->first_burst, out_len) -
 433                                                task->imm_count;
 434                         r2t->data_offset = task->imm_count;
 435                         r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
 436                         r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
 437                 }
 438
 439                 if (!task->unsol_r2t.data_length)
 440                         /* No unsolicit Data-Out's */
 441                         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 442         } else {
 443                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 444                 zero_data(hdr->dlength);
 445                 hdr->data_length = cpu_to_be32(scsi_in(sc)->length);
 446
 447                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
 448                         hdr->flags |= ISCSI_FLAG_CMD_READ;
 449         }
 450
 451         /* calculate size of additional header segments (AHSs) */
 452         hdrlength = task->hdr_len - sizeof(*hdr);
 453
 454         WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
 455         hdrlength /= ISCSI_PAD_LEN;
 456
 457         WARN_ON(hdrlength >= 256);
 458         hdr->hlength = hdrlength & 0xFF;
 459         hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
 460
 461         if (session->tt->init_task && session->tt->init_task(task))
 462                 return -EIO;
 463
 464         task->state = ISCSI_TASK_RUNNING;
 465         session->cmdsn++;
 466
 467         conn->scsicmd_pdus_cnt++;
 468         ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
 469                           "itt 0x%x len %d bidi_len %d cmdsn %d win %d]\n",
 470                           scsi_bidi_cmnd(sc) ? "bidirectional" :
 471                           sc->sc_data_direction == DMA_TO_DEVICE ?
 472                           "write" : "read", conn->id, sc, sc->cmnd[0],
 473                           task->itt, scsi_bufflen(sc),
 474                           scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
 475                           session->cmdsn,
 476                           session->max_cmdsn - session->exp_cmdsn + 1);
 477         return 0;
 478 }
 479
 480 /**
 481  * iscsi_free_task - free a task
 482  * @task: iscsi cmd task
 483  *
 484  * Must be called with session lock.
 485  * This function returns the scsi command to scsi-ml or cleans
 486  * up mgmt tasks then returns the task to the pool.
 487  */
 488 static void iscsi_free_task(struct iscsi_task *task)
 489 {
 490         struct iscsi_conn *conn = task->conn;
 491         struct iscsi_session *session = conn->session;
 492         struct scsi_cmnd *sc = task->sc;
 493         int oldstate = task->state;
 494
 495         ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
 496                           task->itt, task->state, task->sc);
 497
 498         session->tt->cleanup_task(task);
 499         task->state = ISCSI_TASK_FREE;
 500         task->sc = NULL;
 501         /*
 502          * login task is preallocated so do not free
 503          */
 504         if (conn->login_task == task)
 505                 return;
 506
 507         kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
 508
 509         if (sc) {
 510                 /* SCSI eh reuses commands to verify us */
 511                 sc->SCp.ptr = NULL;
 512                 /*
 513                  * queue command may call this to free the task, so
 514                  * it will decide how to return sc to scsi-ml.
 515                  */
 516                 if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
 517                         sc->scsi_done(sc);
 518         }
 519 }
 520
 521 void __iscsi_get_task(struct iscsi_task *task)
 522 {
 523         atomic_inc(&task->refcount);
 524 }
 525 EXPORT_SYMBOL_GPL(__iscsi_get_task);
 526
 527 void __iscsi_put_task(struct iscsi_task *task)
 528 {
 529         if (atomic_dec_and_test(&task->refcount))
 530                 iscsi_free_task(task);
 531 }
 532 EXPORT_SYMBOL_GPL(__iscsi_put_task);
 533
 534 void iscsi_put_task(struct iscsi_task *task)
 535 {
 536         struct iscsi_session *session = task->conn->session;
 537
 538         spin_lock_bh(&session->lock);
 539         __iscsi_put_task(task);
 540         spin_unlock_bh(&session->lock);
 541 }
 542 EXPORT_SYMBOL_GPL(iscsi_put_task);
 543
 544 /**
 545  * iscsi_complete_task - finish a task
 546  * @task: iscsi cmd task
 547  * @state: state to complete task with
 548  *
 549  * Must be called with session lock.
 550  */
 551 static void iscsi_complete_task(struct iscsi_task *task, int state)
 552 {
 553         struct iscsi_conn *conn = task->conn;
 554
 555         ISCSI_DBG_SESSION(conn->session,
 556                           "complete task itt 0x%x state %d sc %p\n",
 557                           task->itt, task->state, task->sc);
 558         if (task->state == ISCSI_TASK_COMPLETED ||
 559             task->state == ISCSI_TASK_ABRT_TMF ||
 560             task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
 561             task->state == ISCSI_TASK_REQUEUE_SCSIQ)
 562                 return;
 563         WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
 564         task->state = state;
 565
 566         if (!list_empty(&task->running))
 567                 list_del_init(&task->running);
 568
 569         if (conn->task == task)
 570                 conn->task = NULL;
 571
 572         if (conn->ping_task == task)
 573                 conn->ping_task = NULL;
 574
 575         /* release get from queueing */
 576         __iscsi_put_task(task);
 577 }
 578
 579 /**
 580  * iscsi_complete_scsi_task - finish scsi task normally
 581  * @task: iscsi task for scsi cmd
 582  * @exp_cmdsn: expected cmd sn in cpu format
 583  * @max_cmdsn: max cmd sn in cpu format
 584  *
 585  * This is used when drivers do not need or cannot perform
 586  * lower level pdu processing.
 587  *
 588  * Called with session lock
 589  */
 590 void iscsi_complete_scsi_task(struct iscsi_task *task,
 591                               uint32_t exp_cmdsn, uint32_t max_cmdsn)
 592 {
 593         struct iscsi_conn *conn = task->conn;
 594
 595         ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
 596
 597         conn->last_recv = jiffies;
 598         __iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
 599         iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 600 }
 601 EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
 602
 603
 604 /*
 605  * session lock must be held and if not called for a task that is
 606  * still pending or from the xmit thread, then xmit thread must
 607  * be suspended.
 608  */
 609 static void fail_scsi_task(struct iscsi_task *task, int err)
 610 {
 611         struct iscsi_conn *conn = task->conn;
 612         struct scsi_cmnd *sc;
 613         int state;
 614
 615         /*
 616          * if a command completes and we get a successful tmf response
 617          * we will hit this because the scsi eh abort code does not take
 618          * a ref to the task.
 619          */
 620         sc = task->sc;
 621         if (!sc)
 622                 return;
 623
 624         if (task->state == ISCSI_TASK_PENDING) {
 625                 /*
 626                  * cmd never made it to the xmit thread, so we should not count
 627                  * the cmd in the sequencing
 628                  */
 629                 conn->session->queued_cmdsn--;
 630                 /* it was never sent so just complete like normal */
 631                 state = ISCSI_TASK_COMPLETED;
 632         } else if (err == DID_TRANSPORT_DISRUPTED)
 633                 state = ISCSI_TASK_ABRT_SESS_RECOV;
 634         else
 635                 state = ISCSI_TASK_ABRT_TMF;
 636
 637         sc->result = err << 16;
 638         if (!scsi_bidi_cmnd(sc))
 639                 scsi_set_resid(sc, scsi_bufflen(sc));
 640         else {
 641                 scsi_out(sc)->resid = scsi_out(sc)->length;
 642                 scsi_in(sc)->resid = scsi_in(sc)->length;
 643         }
 644
 645         iscsi_complete_task(task, state);
 646 }
 647
 648 static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
 649                                 struct iscsi_task *task)
 650 {
 651         struct iscsi_session *session = conn->session;
 652         struct iscsi_hdr *hdr = task->hdr;
 653         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 654         uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
 655
 656         if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
 657                 return -ENOTCONN;
 658
 659         if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
 660                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 661         /*
 662          * pre-format CmdSN for outgoing PDU.
 663          */
 664         nop->cmdsn = cpu_to_be32(session->cmdsn);
 665         if (hdr->itt != RESERVED_ITT) {
 666                 /*
 667                  * TODO: We always use immediate for normal session pdus.
 668                  * If we start to send tmfs or nops as non-immediate then
 669                  * we should start checking the cmdsn numbers for mgmt tasks.
 670                  *
 671                  * During discovery sessions iscsid sends TEXT as non immediate,
 672                  * but we always only send one PDU at a time.
 673                  */
 674                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 675                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 676                         session->queued_cmdsn++;
 677                         session->cmdsn++;
 678                 }
 679         }
 680
 681         if (session->tt->init_task && session->tt->init_task(task))
 682                 return -EIO;
 683
 684         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 685                 session->state = ISCSI_STATE_LOGGING_OUT;
 686
 687         task->state = ISCSI_TASK_RUNNING;
 688         ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
 689                           "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
 690                           hdr->itt, task->data_count);
 691         return 0;
 692 }
 693
 694 static struct iscsi_task *
 695 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 696                       char *data, uint32_t data_size)
 697 {
 698         struct iscsi_session *session = conn->session;
 699         struct iscsi_host *ihost = shost_priv(session->host);
 700         uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
 701         struct iscsi_task *task;
 702         itt_t itt;
 703
 704         if (session->state == ISCSI_STATE_TERMINATE)
 705                 return NULL;
 706
 707         if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
 708                 /*
 709                  * Login and Text are sent serially, in
 710                  * request-followed-by-response sequence.
 711                  * Same task can be used. Same ITT must be used.
 712                  * Note that login_task is preallocated at conn_create().
 713                  */
 714                 if (conn->login_task->state != ISCSI_TASK_FREE) {
 715                         iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
 716                                           "progress. Cannot start new task.\n");
 717                         return NULL;
 718                 }
 719
 720                 if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) {
 721                         iscsi_conn_printk(KERN_ERR, conn, "Invalid buffer len of %u for login task. Max len is %u\n", data_size, ISCSI_DEF_MAX_RECV_SEG_LEN);
 722                         return NULL;
 723                 }
 724
 725                 task = conn->login_task;
 726         } else {
 727                 if (session->state != ISCSI_STATE_LOGGED_IN)
 728                         return NULL;
 729
 730                 if (data_size != 0) {
 731                         iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode);
 732                         return NULL;
 733                 }
 734
 735                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 736                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 737
 738                 if (!kfifo_out(&session->cmdpool.queue,
 739                                  (void*)&task, sizeof(void*)))
 740                         return NULL;
 741         }
 742         /*
 743          * released in complete pdu for task we expect a response for, and
 744          * released by the lld when it has transmitted the task for
 745          * pdus we do not expect a response for.
 746          */
 747         atomic_set(&task->refcount, 1);
 748         task->conn = conn;
 749         task->sc = NULL;
 750         INIT_LIST_HEAD(&task->running);
 751         task->state = ISCSI_TASK_PENDING;
 752
 753         if (data_size) {
 754                 memcpy(task->data, data, data_size);
 755                 task->data_count = data_size;
 756         } else
 757                 task->data_count = 0;
 758
 759         if (conn->session->tt->alloc_pdu) {
 760                 if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
 761                         iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
 762                                          "pdu for mgmt task.\n");
 763                         goto free_task;
 764                 }
 765         }
 766
 767         itt = task->hdr->itt;
 768         task->hdr_len = sizeof(struct iscsi_hdr);
 769         memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
 770
 771         if (hdr->itt != RESERVED_ITT) {
 772                 if (session->tt->parse_pdu_itt)
 773                         task->hdr->itt = itt;
 774                 else
 775                         task->hdr->itt = build_itt(task->itt,
 776                                                    task->conn->session->age);
 777         }
 778
 779         if (!ihost->workq) {
 780                 if (iscsi_prep_mgmt_task(conn, task))
 781                         goto free_task;
 782
 783                 if (session->tt->xmit_task(task))
 784                         goto free_task;
 785         } else {
 786                 list_add_tail(&task->running, &conn->mgmtqueue);
 787                 iscsi_conn_queue_work(conn);
 788         }
 789
 790         return task;
 791
 792 free_task:
 793         __iscsi_put_task(task);
 794         return NULL;
 795 }
 796
 797 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 798                         char *data, uint32_t data_size)
 799 {
 800         struct iscsi_conn *conn = cls_conn->dd_data;
 801         struct iscsi_session *session = conn->session;
 802         int err = 0;
 803
 804         spin_lock_bh(&session->lock);
 805         if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
 806                 err = -EPERM;
 807         spin_unlock_bh(&session->lock);
 808         return err;
 809 }
 810 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 811
 812 /**
 813  * iscsi_cmd_rsp - SCSI Command Response processing
 814  * @conn: iscsi connection
 815  * @hdr: iscsi header
 816  * @task: scsi command task
 817  * @data: cmd data buffer
 818  * @datalen: len of buffer
 819  *
 820  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 821  * then completes the command and task.
 822  **/
 823 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 824                                struct iscsi_task *task, char *data,
 825                                int datalen)
 826 {
 827         struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr;
 828         struct iscsi_session *session = conn->session;
 829         struct scsi_cmnd *sc = task->sc;
 830
 831         iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
 832         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 833
 834         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 835
 836         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 837                 sc->result = DID_ERROR << 16;
 838                 goto out;
 839         }
 840
 841         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 842                 uint16_t senselen;
 843
 844                 if (datalen < 2) {
 845 invalid_datalen:
 846                         iscsi_conn_printk(KERN_ERR,  conn,
 847                                          "Got CHECK_CONDITION but invalid data "
 848                                          "buffer size of %d\n", datalen);
 849                         sc->result = DID_BAD_TARGET << 16;
 850                         goto out;
 851                 }
 852
 853                 senselen = get_unaligned_be16(data);
 854                 if (datalen < senselen)
 855                         goto invalid_datalen;
 856
 857                 memcpy(sc->sense_buffer, data + 2,
 858                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 859                 ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
 860                                   min_t(uint16_t, senselen,
 861                                   SCSI_SENSE_BUFFERSIZE));
 862         }
 863
 864         if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
 865                            ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
 866                 int res_count = be32_to_cpu(rhdr->bi_residual_count);
 867
 868                 if (scsi_bidi_cmnd(sc) && res_count > 0 &&
 869                                 (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
 870                                  res_count <= scsi_in(sc)->length))
 871                         scsi_in(sc)->resid = res_count;
 872                 else
 873                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 874         }
 875
 876         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 877                            ISCSI_FLAG_CMD_OVERFLOW)) {
 878                 int res_count = be32_to_cpu(rhdr->residual_count);
 879
 880                 if (res_count > 0 &&
 881                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 882                      res_count <= scsi_bufflen(sc)))
 883                         /* write side for bidi or uni-io set_resid */
 884                         scsi_set_resid(sc, res_count);
 885                 else
 886                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 887         }
 888 out:
 889         ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
 890                           sc, sc->result, task->itt);
 891         conn->scsirsp_pdus_cnt++;
 892         iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 893 }
 894
 895 /**
 896  * iscsi_data_in_rsp - SCSI Data-In Response processing
 897  * @conn: iscsi connection
 898  * @hdr:  iscsi pdu
 899  * @task: scsi command task
 900  **/
 901 static void
 902 iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 903                   struct iscsi_task *task)
 904 {
 905         struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
 906         struct scsi_cmnd *sc = task->sc;
 907
 908         if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
 909                 return;
 910
 911         iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
 912         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 913         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 914         if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
 915                            ISCSI_FLAG_DATA_OVERFLOW)) {
 916                 int res_count = be32_to_cpu(rhdr->residual_count);
 917
 918                 if (res_count > 0 &&
 919                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 920                      res_count <= scsi_in(sc)->length))
 921                         scsi_in(sc)->resid = res_count;
 922                 else
 923                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 924         }
 925
 926         ISCSI_DBG_SESSION(conn->session, "data in with status done "
 927                           "[sc %p res %d itt 0x%x]\n",
 928                           sc, sc->result, task->itt);
 929         conn->scsirsp_pdus_cnt++;
 930         iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 931 }
 932
 933 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 934 {
 935         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 936
 937         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 938         conn->tmfrsp_pdus_cnt++;
 939
 940         if (conn->tmf_state != TMF_QUEUED)
 941                 return;
 942
 943         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 944                 conn->tmf_state = TMF_SUCCESS;
 945         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 946                 conn->tmf_state = TMF_NOT_FOUND;
 947         else
 948                 conn->tmf_state = TMF_FAILED;
 949         wake_up(&conn->ehwait);
 950 }
 951
 952 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 953 {
 954         struct iscsi_nopout hdr;
 955         struct iscsi_task *task;
 956
 957         if (!rhdr && conn->ping_task)
 958                 return;
 959
 960         memset(&hdr, 0, sizeof(struct iscsi_nopout));
 961         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
 962         hdr.flags = ISCSI_FLAG_CMD_FINAL;
 963
 964         if (rhdr) {
 965                 hdr.lun = rhdr->lun;
 966                 hdr.ttt = rhdr->ttt;
 967                 hdr.itt = RESERVED_ITT;
 968         } else
 969                 hdr.ttt = RESERVED_ITT;
 970
 971         task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
 972         if (!task)
 973                 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
 974         else if (!rhdr) {
 975                 /* only track our nops */
 976                 conn->ping_task = task;
 977                 conn->last_ping = jiffies;
 978         }
 979 }
 980
 981 static int iscsi_nop_out_rsp(struct iscsi_task *task,
 982                              struct iscsi_nopin *nop, char *data, int datalen)
 983 {
 984         struct iscsi_conn *conn = task->conn;
 985         int rc = 0;
 986
 987         if (conn->ping_task != task) {
 988                 /*
 989                  * If this is not in response to one of our
 990                  * nops then it must be from userspace.
 991                  */
 992                 if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
 993                                    data, datalen))
 994                         rc = ISCSI_ERR_CONN_FAILED;
 995         } else
 996                 mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
 997         iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 998         return rc;
 999 }
1000
1001 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1002                                char *data, int datalen)
1003 {
1004         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
1005         struct iscsi_hdr rejected_pdu;
1006         int opcode, rc = 0;
1007
1008         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
1009
1010         if (ntoh24(reject->dlength) > datalen ||
1011             ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
1012                 iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
1013                                   "pdu. Invalid data length (pdu dlength "
1014                                   "%u, datalen %d\n", ntoh24(reject->dlength),
1015                                   datalen);
1016                 return ISCSI_ERR_PROTO;
1017         }
1018         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
1019         opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
1020
1021         switch (reject->reason) {
1022         case ISCSI_REASON_DATA_DIGEST_ERROR:
1023                 iscsi_conn_printk(KERN_ERR, conn,
1024                                   "pdu (op 0x%x itt 0x%x) rejected "
1025                                   "due to DataDigest error.\n",
1026                                   rejected_pdu.itt, opcode);
1027                 break;
1028         case ISCSI_REASON_IMM_CMD_REJECT:
1029                 iscsi_conn_printk(KERN_ERR, conn,
1030                                   "pdu (op 0x%x itt 0x%x) rejected. Too many "
1031                                   "immediate commands.\n",
1032                                   rejected_pdu.itt, opcode);
1033                 /*
1034                  * We only send one TMF at a time so if the target could not
1035                  * handle it, then it should get fixed (RFC mandates that
1036                  * a target can handle one immediate TMF per conn).
1037                  *
1038                  * For nops-outs, we could have sent more than one if
1039                  * the target is sending us lots of nop-ins
1040                  */
1041                 if (opcode != ISCSI_OP_NOOP_OUT)
1042                         return 0;
1043
1044                  if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG))
1045                         /*
1046                          * nop-out in response to target's nop-out rejected.
1047                          * Just resend.
1048                          */
1049                         iscsi_send_nopout(conn,
1050                                           (struct iscsi_nopin*)&rejected_pdu);
1051                 else {
1052                         struct iscsi_task *task;
1053                         /*
1054                          * Our nop as ping got dropped. We know the target
1055                          * and transport are ok so just clean up
1056                          */
1057                         task = iscsi_itt_to_task(conn, rejected_pdu.itt);
1058                         if (!task) {
1059                                 iscsi_conn_printk(KERN_ERR, conn,
1060                                                  "Invalid pdu reject. Could "
1061                                                  "not lookup rejected task.\n");
1062                                 rc = ISCSI_ERR_BAD_ITT;
1063                         } else
1064                                 rc = iscsi_nop_out_rsp(task,
1065                                         (struct iscsi_nopin*)&rejected_pdu,
1066                                         NULL, 0);
1067                 }
1068                 break;
1069         default:
1070                 iscsi_conn_printk(KERN_ERR, conn,
1071                                   "pdu (op 0x%x itt 0x%x) rejected. Reason "
1072                                   "code 0x%x\n", rejected_pdu.itt,
1073                                   rejected_pdu.opcode, reject->reason);
1074                 break;
1075         }
1076         return rc;
1077 }
1078
1079 /**
1080  * iscsi_itt_to_task - look up task by itt
1081  * @conn: iscsi connection
1082  * @itt: itt
1083  *
1084  * This should be used for mgmt tasks like login and nops, or if
1085  * the LDD's itt space does not include the session age.
1086  *
1087  * The session lock must be held.
1088  */
1089 struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
1090 {
1091         struct iscsi_session *session = conn->session;
1092         int i;
1093
1094         if (itt == RESERVED_ITT)
1095                 return NULL;
1096
1097         if (session->tt->parse_pdu_itt)
1098                 session->tt->parse_pdu_itt(conn, itt, &i, NULL);
1099         else
1100                 i = get_itt(itt);
1101         if (i >= session->cmds_max)
1102                 return NULL;
1103
1104         return session->cmds[i];
1105 }
1106 EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
1107
1108 /**
1109  * __iscsi_complete_pdu - complete pdu
1110  * @conn: iscsi conn
1111  * @hdr: iscsi header
1112  * @data: data buffer
1113  * @datalen: len of data buffer
1114  *
1115  * Completes pdu processing by freeing any resources allocated at
1116  * queuecommand or send generic. session lock must be held and verify
1117  * itt must have been called.
1118  */
1119 int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1120                          char *data, int datalen)
1121 {
1122         struct iscsi_session *session = conn->session;
1123         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
1124         struct iscsi_task *task;
1125         uint32_t itt;
1126
1127         conn->last_recv = jiffies;
1128         rc = iscsi_verify_itt(conn, hdr->itt);
1129         if (rc)
1130                 return rc;
1131
1132         if (hdr->itt != RESERVED_ITT)
1133                 itt = get_itt(hdr->itt);
1134         else
1135                 itt = ~0U;
1136
1137         ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
1138                           opcode, conn->id, itt, datalen);
1139
1140         if (itt == ~0U) {
1141                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1142
1143                 switch(opcode) {
1144                 case ISCSI_OP_NOOP_IN:
1145                         if (datalen) {
1146                                 rc = ISCSI_ERR_PROTO;
1147                                 break;
1148                         }
1149
1150                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
1151                                 break;
1152
1153                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
1154                         break;
1155                 case ISCSI_OP_REJECT:
1156                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
1157                         break;
1158                 case ISCSI_OP_ASYNC_EVENT:
1159                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1160                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1161                                 rc = ISCSI_ERR_CONN_FAILED;
1162                         break;
1163                 default:
1164                         rc = ISCSI_ERR_BAD_OPCODE;
1165                         break;
1166                 }
1167                 goto out;
1168         }
1169
1170         switch(opcode) {
1171         case ISCSI_OP_SCSI_CMD_RSP:
1172         case ISCSI_OP_SCSI_DATA_IN:
1173                 task = iscsi_itt_to_ctask(conn, hdr->itt);
1174                 if (!task)
1175                         return ISCSI_ERR_BAD_ITT;
1176                 task->last_xfer = jiffies;
1177                 break;
1178         case ISCSI_OP_R2T:
1179                 /*
1180                  * LLD handles R2Ts if they need to.
1181                  */
1182                 return 0;
1183         case ISCSI_OP_LOGOUT_RSP:
1184         case ISCSI_OP_LOGIN_RSP:
1185         case ISCSI_OP_TEXT_RSP:
1186         case ISCSI_OP_SCSI_TMFUNC_RSP:
1187         case ISCSI_OP_NOOP_IN:
1188                 task = iscsi_itt_to_task(conn, hdr->itt);
1189                 if (!task)
1190                         return ISCSI_ERR_BAD_ITT;
1191                 break;
1192         default:
1193                 return ISCSI_ERR_BAD_OPCODE;
1194         }
1195
1196         switch(opcode) {
1197         case ISCSI_OP_SCSI_CMD_RSP:
1198                 iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
1199                 break;
1200         case ISCSI_OP_SCSI_DATA_IN:
1201                 iscsi_data_in_rsp(conn, hdr, task);
1202                 break;
1203         case ISCSI_OP_LOGOUT_RSP:
1204                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1205                 if (datalen) {
1206                         rc = ISCSI_ERR_PROTO;
1207                         break;
1208                 }
1209                 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1210                 goto recv_pdu;
1211         case ISCSI_OP_LOGIN_RSP:
1212         case ISCSI_OP_TEXT_RSP:
1213                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1214                 /*
1215                  * login related PDU's exp_statsn is handled in
1216                  * userspace
1217                  */
1218                 goto recv_pdu;
1219         case ISCSI_OP_SCSI_TMFUNC_RSP:
1220                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1221                 if (datalen) {
1222                         rc = ISCSI_ERR_PROTO;
1223                         break;
1224                 }
1225
1226                 iscsi_tmf_rsp(conn, hdr);
1227                 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1228                 break;
1229         case ISCSI_OP_NOOP_IN:
1230                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1231                 if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
1232                         rc = ISCSI_ERR_PROTO;
1233                         break;
1234                 }
1235                 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1236
1237                 rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
1238                                        data, datalen);
1239                 break;
1240         default:
1241                 rc = ISCSI_ERR_BAD_OPCODE;
1242                 break;
1243         }
1244
1245 out:
1246         return rc;
1247 recv_pdu:
1248         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1249                 rc = ISCSI_ERR_CONN_FAILED;
1250         iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1251         return rc;
1252 }
1253 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
1254
1255 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1256                        char *data, int datalen)
1257 {
1258         int rc;
1259
1260         spin_lock(&conn->session->lock);
1261         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
1262         spin_unlock(&conn->session->lock);
1263         return rc;
1264 }
1265 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
1266
1267 int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
1268 {
1269         struct iscsi_session *session = conn->session;
1270         int age = 0, i = 0;
1271
1272         if (itt == RESERVED_ITT)
1273                 return 0;
1274
1275         if (session->tt->parse_pdu_itt)
1276                 session->tt->parse_pdu_itt(conn, itt, &i, &age);
1277         else {
1278                 i = get_itt(itt);
1279                 age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
1280         }
1281
1282         if (age != session->age) {
1283                 iscsi_conn_printk(KERN_ERR, conn,
1284                                   "received itt %x expected session age (%x)\n",
1285                                   (__force u32)itt, session->age);
1286                 return ISCSI_ERR_BAD_ITT;
1287         }
1288
1289         if (i >= session->cmds_max) {
1290                 iscsi_conn_printk(KERN_ERR, conn,
1291                                   "received invalid itt index %u (max cmds "
1292                                    "%u.\n", i, session->cmds_max);
1293                 return ISCSI_ERR_BAD_ITT;
1294         }
1295         return 0;
1296 }
1297 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
1298
1299 /**
1300  * iscsi_itt_to_ctask - look up ctask by itt
1301  * @conn: iscsi connection
1302  * @itt: itt
1303  *
1304  * This should be used for cmd tasks.
1305  *
1306  * The session lock must be held.
1307  */
1308 struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
1309 {
1310         struct iscsi_task *task;
1311
1312         if (iscsi_verify_itt(conn, itt))
1313                 return NULL;
1314
1315         task = iscsi_itt_to_task(conn, itt);
1316         if (!task || !task->sc)
1317                 return NULL;
1318
1319         if (task->sc->SCp.phase != conn->session->age) {
1320                 iscsi_session_printk(KERN_ERR, conn->session,
1321                                   "task's session age %d, expected %d\n",
1322                                   task->sc->SCp.phase, conn->session->age);
1323                 return NULL;
1324         }
1325
1326         return task;
1327 }
1328 EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
1329
1330 void iscsi_session_failure(struct iscsi_session *session,
1331                            enum iscsi_err err)
1332 {
1333         struct iscsi_conn *conn;
1334         struct device *dev;
1335
1336         spin_lock_bh(&session->lock);
1337         conn = session->leadconn;
1338         if (session->state == ISCSI_STATE_TERMINATE || !conn) {
1339                 spin_unlock_bh(&session->lock);
1340                 return;
1341         }
1342
1343         dev = get_device(&conn->cls_conn->dev);
1344         spin_unlock_bh(&session->lock);
1345         if (!dev)
1346                 return;
1347         /*
1348          * if the host is being removed bypass the connection
1349          * recovery initialization because we are going to kill
1350          * the session.
1351          */
1352         if (err == ISCSI_ERR_INVALID_HOST)
1353                 iscsi_conn_error_event(conn->cls_conn, err);
1354         else
1355                 iscsi_conn_failure(conn, err);
1356         put_device(dev);
1357 }
1358 EXPORT_SYMBOL_GPL(iscsi_session_failure);
1359
1360 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
1361 {
1362         struct iscsi_session *session = conn->session;
1363
1364         spin_lock_bh(&session->lock);
1365         if (session->state == ISCSI_STATE_FAILED) {
1366                 spin_unlock_bh(&session->lock);
1367                 return;
1368         }
1369
1370         if (conn->stop_stage == 0)
1371                 session->state = ISCSI_STATE_FAILED;
1372         spin_unlock_bh(&session->lock);
1373
1374         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1375         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1376         iscsi_conn_error_event(conn->cls_conn, err);
1377 }
1378 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
1379
1380 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
1381 {
1382         struct iscsi_session *session = conn->session;
1383
1384         /*
1385          * Check for iSCSI window and take care of CmdSN wrap-around
1386          */
1387         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
1388                 ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
1389                                   "%u MaxCmdSN %u CmdSN %u/%u\n",
1390                                   session->exp_cmdsn, session->max_cmdsn,
1391                                   session->cmdsn, session->queued_cmdsn);
1392                 return -ENOSPC;
1393         }
1394         return 0;
1395 }
1396
1397 static int iscsi_xmit_task(struct iscsi_conn *conn)
1398 {
1399         struct iscsi_task *task = conn->task;
1400         int rc;
1401
1402         if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx))
1403                 return -ENODATA;
1404
1405         __iscsi_get_task(task);
1406         spin_unlock_bh(&conn->session->lock);
1407         rc = conn->session->tt->xmit_task(task);
1408         spin_lock_bh(&conn->session->lock);
1409         if (!rc) {
1410                 /* done with this task */
1411                 task->last_xfer = jiffies;
1412                 conn->task = NULL;
1413         }
1414         __iscsi_put_task(task);
1415         return rc;
1416 }
1417
1418 /**
1419  * iscsi_requeue_task - requeue task to run from session workqueue
1420  * @task: task to requeue
1421  *
1422  * LLDs that need to run a task from the session workqueue should call
1423  * this. The session lock must be held. This should only be called
1424  * by software drivers.
1425  */
1426 void iscsi_requeue_task(struct iscsi_task *task)
1427 {
1428         struct iscsi_conn *conn = task->conn;
1429
1430         /*
1431          * this may be on the requeue list already if the xmit_task callout
1432          * is handling the r2ts while we are adding new ones
1433          */
1434         if (list_empty(&task->running))
1435                 list_add_tail(&task->running, &conn->requeue);
1436         iscsi_conn_queue_work(conn);
1437 }
1438 EXPORT_SYMBOL_GPL(iscsi_requeue_task);
1439
1440 /**
1441  * iscsi_data_xmit - xmit any command into the scheduled connection
1442  * @conn: iscsi connection
1443  *
1444  * Notes:
1445  *      The function can return -EAGAIN in which case the caller must
1446  *      re-schedule it again later or recover. '0' return code means
1447  *      successful xmit.
1448  **/
1449 static int iscsi_data_xmit(struct iscsi_conn *conn)
1450 {
1451         struct iscsi_task *task;
1452         int rc = 0;
1453
1454         spin_lock_bh(&conn->session->lock);
1455         if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1456                 ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
1457                 spin_unlock_bh(&conn->session->lock);
1458                 return -ENODATA;
1459         }
1460
1461         if (conn->task) {
1462                 rc = iscsi_xmit_task(conn);
1463                 if (rc)
1464                         goto done;
1465         }
1466
1467         /*
1468          * process mgmt pdus like nops before commands since we should
1469          * only have one nop-out as a ping from us and targets should not
1470          * overflow us with nop-ins
1471          */
1472 check_mgmt:
1473         while (!list_empty(&conn->mgmtqueue)) {
1474                 conn->task = list_entry(conn->mgmtqueue.next,
1475                                          struct iscsi_task, running);
1476                 list_del_init(&conn->task->running);
1477                 if (iscsi_prep_mgmt_task(conn, conn->task)) {
1478                         __iscsi_put_task(conn->task);
1479                         conn->task = NULL;
1480                         continue;
1481                 }
1482                 rc = iscsi_xmit_task(conn);
1483                 if (rc)
1484                         goto done;
1485         }
1486
1487         /* process pending command queue */
1488         while (!list_empty(&conn->cmdqueue)) {
1489                 conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task,
1490                                         running);
1491                 list_del_init(&conn->task->running);
1492                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1493                         fail_scsi_task(conn->task, DID_IMM_RETRY);
1494                         continue;
1495                 }
1496                 rc = iscsi_prep_scsi_cmd_pdu(conn->task);
1497                 if (rc) {
1498                         if (rc == -ENOMEM || rc == -EACCES) {
1499                                 list_add_tail(&conn->task->running,
1500                                               &conn->cmdqueue);
1501                                 conn->task = NULL;
1502                                 goto done;
1503                         } else
1504                                 fail_scsi_task(conn->task, DID_ABORT);
1505                         continue;
1506                 }
1507                 rc = iscsi_xmit_task(conn);
1508                 if (rc)
1509                         goto done;
1510                 /*
1511                  * we could continuously get new task requests so
1512                  * we need to check the mgmt queue for nops that need to
1513                  * be sent to aviod starvation
1514                  */
1515                 if (!list_empty(&conn->mgmtqueue))
1516                         goto check_mgmt;
1517         }
1518
1519         while (!list_empty(&conn->requeue)) {
1520                 /*
1521                  * we always do fastlogout - conn stop code will clean up.
1522                  */
1523                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1524                         break;
1525
1526                 task = list_entry(conn->requeue.next, struct iscsi_task,
1527                                   running);
1528                 if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
1529                         break;
1530
1531                 conn->task = task;
1532                 list_del_init(&conn->task->running);
1533                 conn->task->state = ISCSI_TASK_RUNNING;
1534                 rc = iscsi_xmit_task(conn);
1535                 if (rc)
1536                         goto done;
1537                 if (!list_empty(&conn->mgmtqueue))
1538                         goto check_mgmt;
1539         }
1540         spin_unlock_bh(&conn->session->lock);
1541         return -ENODATA;
1542
1543 done:
1544         spin_unlock_bh(&conn->session->lock);
1545         return rc;
1546 }
1547
1548 static void iscsi_xmitworker(struct work_struct *work)
1549 {
1550         struct iscsi_conn *conn =
1551                 container_of(work, struct iscsi_conn, xmitwork);
1552         int rc;
1553         /*
1554          * serialize Xmit worker on a per-connection basis.
1555          */
1556         do {
1557                 rc = iscsi_data_xmit(conn);
1558         } while (rc >= 0 || rc == -EAGAIN);
1559 }
1560
1561 static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
1562                                                   struct scsi_cmnd *sc)
1563 {
1564         struct iscsi_task *task;
1565
1566         if (!kfifo_out(&conn->session->cmdpool.queue,
1567                          (void *) &task, sizeof(void *)))
1568                 return NULL;
1569
1570         sc->SCp.phase = conn->session->age;
1571         sc->SCp.ptr = (char *) task;
1572
1573         atomic_set(&task->refcount, 1);
1574         task->state = ISCSI_TASK_PENDING;
1575         task->conn = conn;
1576         task->sc = sc;
1577         task->have_checked_conn = false;
1578         task->last_timeout = jiffies;
1579         task->last_xfer = jiffies;
1580         INIT_LIST_HEAD(&task->running);
1581         return task;
1582 }
1583
1584 enum {
1585         FAILURE_BAD_HOST = 1,
1586         FAILURE_SESSION_FAILED,
1587         FAILURE_SESSION_FREED,
1588         FAILURE_WINDOW_CLOSED,
1589         FAILURE_OOM,
1590         FAILURE_SESSION_TERMINATE,
1591         FAILURE_SESSION_IN_RECOVERY,
1592         FAILURE_SESSION_RECOVERY_TIMEOUT,
1593         FAILURE_SESSION_LOGGING_OUT,
1594         FAILURE_SESSION_NOT_READY,
1595 };
1596
1597 int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
1598 {
1599         struct iscsi_cls_session *cls_session;
1600         struct iscsi_host *ihost;
1601         int reason = 0;
1602         struct iscsi_session *session;
1603         struct iscsi_conn *conn;
1604         struct iscsi_task *task = NULL;
1605
1606         sc->result = 0;
1607         sc->SCp.ptr = NULL;
1608
1609         ihost = shost_priv(host);
1610
1611         cls_session = starget_to_session(scsi_target(sc->device));
1612         session = cls_session->dd_data;
1613         spin_lock_bh(&session->lock);
1614
1615         reason = iscsi_session_chkready(cls_session);
1616         if (reason) {
1617                 sc->result = reason;
1618                 goto fault;
1619         }
1620
1621         if (session->state != ISCSI_STATE_LOGGED_IN) {
1622                 /*
1623                  * to handle the race between when we set the recovery state
1624                  * and block the session we requeue here (commands could
1625                  * be entering our queuecommand while a block is starting
1626                  * up because the block code is not locked)
1627                  */
1628                 switch (session->state) {
1629                 case ISCSI_STATE_FAILED:
1630                 case ISCSI_STATE_IN_RECOVERY:
1631                         reason = FAILURE_SESSION_IN_RECOVERY;
1632                         sc->result = DID_IMM_RETRY << 16;
1633                         break;
1634                 case ISCSI_STATE_LOGGING_OUT:
1635                         reason = FAILURE_SESSION_LOGGING_OUT;
1636                         sc->result = DID_IMM_RETRY << 16;
1637                         break;
1638                 case ISCSI_STATE_RECOVERY_FAILED:
1639                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1640                         sc->result = DID_TRANSPORT_FAILFAST << 16;
1641                         break;
1642                 case ISCSI_STATE_TERMINATE:
1643                         reason = FAILURE_SESSION_TERMINATE;
1644                         sc->result = DID_NO_CONNECT << 16;
1645                         break;
1646                 default:
1647                         reason = FAILURE_SESSION_FREED;
1648                         sc->result = DID_NO_CONNECT << 16;
1649                 }
1650                 goto fault;
1651         }
1652
1653         conn = session->leadconn;
1654         if (!conn) {
1655                 reason = FAILURE_SESSION_FREED;
1656                 sc->result = DID_NO_CONNECT << 16;
1657                 goto fault;
1658         }
1659
1660         if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1661                 reason = FAILURE_SESSION_IN_RECOVERY;
1662                 sc->result = DID_REQUEUE;
1663                 goto fault;
1664         }
1665
1666         if (iscsi_check_cmdsn_window_closed(conn)) {
1667                 reason = FAILURE_WINDOW_CLOSED;
1668                 goto reject;
1669         }
1670
1671         task = iscsi_alloc_task(conn, sc);
1672         if (!task) {
1673                 reason = FAILURE_OOM;
1674                 goto reject;
1675         }
1676
1677         if (!ihost->workq) {
1678                 reason = iscsi_prep_scsi_cmd_pdu(task);
1679                 if (reason) {
1680                         if (reason == -ENOMEM ||  reason == -EACCES) {
1681                                 reason = FAILURE_OOM;
1682                                 goto prepd_reject;
1683                         } else {
1684                                 sc->result = DID_ABORT << 16;
1685                                 goto prepd_fault;
1686                         }
1687                 }
1688                 if (session->tt->xmit_task(task)) {
1689                         session->cmdsn--;
1690                         reason = FAILURE_SESSION_NOT_READY;
1691                         goto prepd_reject;
1692                 }
1693         } else {
1694                 list_add_tail(&task->running, &conn->cmdqueue);
1695                 iscsi_conn_queue_work(conn);
1696         }
1697
1698         session->queued_cmdsn++;
1699         spin_unlock_bh(&session->lock);
1700         return 0;
1701
1702 prepd_reject:
1703         iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1704 reject:
1705         spin_unlock_bh(&session->lock);
1706         ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
1707                           sc->cmnd[0], reason);
1708         return SCSI_MLQUEUE_TARGET_BUSY;
1709
1710 prepd_fault:
1711         iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1712 fault:
1713         spin_unlock_bh(&session->lock);
1714         ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
1715                           sc->cmnd[0], reason);
1716         if (!scsi_bidi_cmnd(sc))
1717                 scsi_set_resid(sc, scsi_bufflen(sc));
1718         else {
1719                 scsi_out(sc)->resid = scsi_out(sc)->length;
1720                 scsi_in(sc)->resid = scsi_in(sc)->length;
1721         }
1722         sc->scsi_done(sc);
1723         return 0;
1724 }
1725 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1726
1727 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth, int reason)
1728 {
1729         switch (reason) {
1730         case SCSI_QDEPTH_DEFAULT:
1731                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1732                 break;
1733         case SCSI_QDEPTH_QFULL:
1734                 scsi_track_queue_full(sdev, depth);
1735                 break;
1736         case SCSI_QDEPTH_RAMP_UP:
1737                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1738                 break;
1739         default:
1740                 return -EOPNOTSUPP;
1741         }
1742         return sdev->queue_depth;
1743 }
1744 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1745
1746 int iscsi_target_alloc(struct scsi_target *starget)
1747 {
1748         struct iscsi_cls_session *cls_session = starget_to_session(starget);
1749         struct iscsi_session *session = cls_session->dd_data;
1750
1751         starget->can_queue = session->scsi_cmds_max;
1752         return 0;
1753 }
1754 EXPORT_SYMBOL_GPL(iscsi_target_alloc);
1755
1756 static void iscsi_tmf_timedout(unsigned long data)
1757 {
1758         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1759         struct iscsi_session *session = conn->session;
1760
1761         spin_lock(&session->lock);
1762         if (conn->tmf_state == TMF_QUEUED) {
1763                 conn->tmf_state = TMF_TIMEDOUT;
1764                 ISCSI_DBG_EH(session, "tmf timedout\n");
1765                 /* unblock eh_abort() */
1766                 wake_up(&conn->ehwait);
1767         }
1768         spin_unlock(&session->lock);
1769 }
1770
1771 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1772                                    struct iscsi_tm *hdr, int age,
1773                                    int timeout)
1774 {
1775         struct iscsi_session *session = conn->session;
1776         struct iscsi_task *task;
1777
1778         task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1779                                       NULL, 0);
1780         if (!task) {
1781                 spin_unlock_bh(&session->lock);
1782                 iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n");
1783                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1784                 spin_lock_bh(&session->lock);
1785                 return -EPERM;
1786         }
1787         conn->tmfcmd_pdus_cnt++;
1788         conn->tmf_timer.expires = timeout * HZ + jiffies;
1789         conn->tmf_timer.function = iscsi_tmf_timedout;
1790         conn->tmf_timer.data = (unsigned long)conn;
1791         add_timer(&conn->tmf_timer);
1792         ISCSI_DBG_EH(session, "tmf set timeout\n");
1793
1794         spin_unlock_bh(&session->lock);
1795         mutex_unlock(&session->eh_mutex);
1796
1797         /*
1798          * block eh thread until:
1799          *
1800          * 1) tmf response
1801          * 2) tmf timeout
1802          * 3) session is terminated or restarted or userspace has
1803          * given up on recovery
1804          */
1805         wait_event_interruptible(conn->ehwait, age != session->age ||
1806                                  session->state != ISCSI_STATE_LOGGED_IN ||
1807                                  conn->tmf_state != TMF_QUEUED);
1808         if (signal_pending(current))
1809                 flush_signals(current);
1810         del_timer_sync(&conn->tmf_timer);
1811
1812         mutex_lock(&session->eh_mutex);
1813         spin_lock_bh(&session->lock);
1814         /* if the session drops it will clean up the task */
1815         if (age != session->age ||
1816             session->state != ISCSI_STATE_LOGGED_IN)
1817                 return -ENOTCONN;
1818         return 0;
1819 }
1820
1821 /*
1822  * Fail commands. session lock held and recv side suspended and xmit
1823  * thread flushed
1824  */
1825 static void fail_scsi_tasks(struct iscsi_conn *conn, unsigned lun,
1826                             int error)
1827 {
1828         struct iscsi_task *task;
1829         int i;
1830
1831         for (i = 0; i < conn->session->cmds_max; i++) {
1832                 task = conn->session->cmds[i];
1833                 if (!task->sc || task->state == ISCSI_TASK_FREE)
1834                         continue;
1835
1836                 if (lun != -1 && lun != task->sc->device->lun)
1837                         continue;
1838
1839                 ISCSI_DBG_SESSION(conn->session,
1840                                   "failing sc %p itt 0x%x state %d\n",
1841                                   task->sc, task->itt, task->state);
1842                 fail_scsi_task(task, error);
1843         }
1844 }
1845
1846 /**
1847  * iscsi_suspend_queue - suspend iscsi_queuecommand
1848  * @conn: iscsi conn to stop queueing IO on
1849  *
1850  * This grabs the session lock to make sure no one is in
1851  * xmit_task/queuecommand, and then sets suspend to prevent
1852  * new commands from being queued. This only needs to be called
1853  * by offload drivers that need to sync a path like ep disconnect
1854  * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
1855  * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
1856  */
1857 void iscsi_suspend_queue(struct iscsi_conn *conn)
1858 {
1859         spin_lock_bh(&conn->session->lock);
1860         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1861         spin_unlock_bh(&conn->session->lock);
1862 }
1863 EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
1864
1865 /**
1866  * iscsi_suspend_tx - suspend iscsi_data_xmit
1867  * @conn: iscsi conn tp stop processing IO on.
1868  *
1869  * This function sets the suspend bit to prevent iscsi_data_xmit
1870  * from sending new IO, and if work is queued on the xmit thread
1871  * it will wait for it to be completed.
1872  */
1873 void iscsi_suspend_tx(struct iscsi_conn *conn)
1874 {
1875         struct Scsi_Host *shost = conn->session->host;
1876         struct iscsi_host *ihost = shost_priv(shost);
1877
1878         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1879         if (ihost->workq)
1880                 flush_workqueue(ihost->workq);
1881 }
1882 EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1883
1884 static void iscsi_start_tx(struct iscsi_conn *conn)
1885 {
1886         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1887         iscsi_conn_queue_work(conn);
1888 }
1889
1890 /*
1891  * We want to make sure a ping is in flight. It has timed out.
1892  * And we are not busy processing a pdu that is making
1893  * progress but got started before the ping and is taking a while
1894  * to complete so the ping is just stuck behind it in a queue.
1895  */
1896 static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
1897 {
1898         if (conn->ping_task &&
1899             time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1900                            (conn->ping_timeout * HZ), jiffies))
1901                 return 1;
1902         else
1903                 return 0;
1904 }
1905
1906 static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
1907 {
1908         enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
1909         struct iscsi_task *task = NULL, *running_task;
1910         struct iscsi_cls_session *cls_session;
1911         struct iscsi_session *session;
1912         struct iscsi_conn *conn;
1913         int i;
1914
1915         cls_session = starget_to_session(scsi_target(sc->device));
1916         session = cls_session->dd_data;
1917
1918         ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
1919
1920         spin_lock(&session->lock);
1921         task = (struct iscsi_task *)sc->SCp.ptr;
1922         if (!task) {
1923                 /*
1924                  * Raced with completion. Blk layer has taken ownership
1925                  * so let timeout code complete it now.
1926                  */
1927                 rc = BLK_EH_HANDLED;
1928                 goto done;
1929         }
1930
1931         if (session->state != ISCSI_STATE_LOGGED_IN) {
1932                 /*
1933                  * We are probably in the middle of iscsi recovery so let
1934                  * that complete and handle the error.
1935                  */
1936                 rc = BLK_EH_RESET_TIMER;
1937                 goto done;
1938         }
1939
1940         conn = session->leadconn;
1941         if (!conn) {
1942                 /* In the middle of shuting down */
1943                 rc = BLK_EH_RESET_TIMER;
1944                 goto done;
1945         }
1946
1947         /*
1948          * If we have sent (at least queued to the network layer) a pdu or
1949          * recvd one for the task since the last timeout ask for
1950          * more time. If on the next timeout we have not made progress
1951          * we can check if it is the task or connection when we send the
1952          * nop as a ping.
1953          */
1954         if (time_after(task->last_xfer, task->last_timeout)) {
1955                 ISCSI_DBG_EH(session, "Command making progress. Asking "
1956                              "scsi-ml for more time to complete. "
1957                              "Last data xfer at %lu. Last timeout was at "
1958                              "%lu\n.", task->last_xfer, task->last_timeout);
1959                 task->have_checked_conn = false;
1960                 rc = BLK_EH_RESET_TIMER;
1961                 goto done;
1962         }
1963
1964         if (!conn->recv_timeout && !conn->ping_timeout)
1965                 goto done;
1966         /*
1967          * if the ping timedout then we are in the middle of cleaning up
1968          * and can let the iscsi eh handle it
1969          */
1970         if (iscsi_has_ping_timed_out(conn)) {
1971                 rc = BLK_EH_RESET_TIMER;
1972                 goto done;
1973         }
1974
1975         for (i = 0; i < conn->session->cmds_max; i++) {
1976                 running_task = conn->session->cmds[i];
1977                 if (!running_task->sc || running_task == task ||
1978                      running_task->state != ISCSI_TASK_RUNNING)
1979                         continue;
1980
1981                 /*
1982                  * Only check if cmds started before this one have made
1983                  * progress, or this could never fail
1984                  */
1985                 if (time_after(running_task->sc->jiffies_at_alloc,
1986                                task->sc->jiffies_at_alloc))
1987                         continue;
1988
1989                 if (time_after(running_task->last_xfer, task->last_timeout)) {
1990                         /*
1991                          * This task has not made progress, but a task
1992                          * started before us has transferred data since
1993                          * we started/last-checked. We could be queueing
1994                          * too many tasks or the LU is bad.
1995                          *
1996                          * If the device is bad the cmds ahead of us on
1997                          * other devs will complete, and this loop will
1998                          * eventually fail starting the scsi eh.
1999                          */
2000                         ISCSI_DBG_EH(session, "Command has not made progress "
2001                                      "but commands ahead of it have. "
2002                                      "Asking scsi-ml for more time to "
2003                                      "complete. Our last xfer vs running task "
2004                                      "last xfer %lu/%lu. Last check %lu.\n",
2005                                      task->last_xfer, running_task->last_xfer,
2006                                      task->last_timeout);
2007                         rc = BLK_EH_RESET_TIMER;
2008                         goto done;
2009                 }
2010         }
2011
2012         /* Assumes nop timeout is shorter than scsi cmd timeout */
2013         if (task->have_checked_conn)
2014                 goto done;
2015
2016         /*
2017          * Checking the transport already or nop from a cmd timeout still
2018          * running
2019          */
2020         if (conn->ping_task) {
2021                 task->have_checked_conn = true;
2022                 rc = BLK_EH_RESET_TIMER;
2023                 goto done;
2024         }
2025
2026         /* Make sure there is a transport check done */
2027         iscsi_send_nopout(conn, NULL);
2028         task->have_checked_conn = true;
2029         rc = BLK_EH_RESET_TIMER;
2030
2031 done:
2032         if (task)
2033                 task->last_timeout = jiffies;
2034         spin_unlock(&session->lock);
2035         ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
2036                      "timer reset" : "nh");
2037         return rc;
2038 }
2039
2040 static void iscsi_check_transport_timeouts(unsigned long data)
2041 {
2042         struct iscsi_conn *conn = (struct iscsi_conn *)data;
2043         struct iscsi_session *session = conn->session;
2044         unsigned long recv_timeout, next_timeout = 0, last_recv;
2045
2046         spin_lock(&session->lock);
2047         if (session->state != ISCSI_STATE_LOGGED_IN)
2048                 goto done;
2049
2050         recv_timeout = conn->recv_timeout;
2051         if (!recv_timeout)
2052                 goto done;
2053
2054         recv_timeout *= HZ;
2055         last_recv = conn->last_recv;
2056
2057         if (iscsi_has_ping_timed_out(conn)) {
2058                 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
2059                                   "expired, recv timeout %d, last rx %lu, "
2060                                   "last ping %lu, now %lu\n",
2061                                   conn->ping_timeout, conn->recv_timeout,
2062                                   last_recv, conn->last_ping, jiffies);
2063                 spin_unlock(&session->lock);
2064                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
2065                 return;
2066         }
2067
2068         if (time_before_eq(last_recv + recv_timeout, jiffies)) {
2069                 /* send a ping to try to provoke some traffic */
2070                 ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
2071                 iscsi_send_nopout(conn, NULL);
2072                 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
2073         } else
2074                 next_timeout = last_recv + recv_timeout;
2075
2076         ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
2077         mod_timer(&conn->transport_timer, next_timeout);
2078 done:
2079         spin_unlock(&session->lock);
2080 }
2081
2082 static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
2083                                       struct iscsi_tm *hdr)
2084 {
2085         memset(hdr, 0, sizeof(*hdr));
2086         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2087         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
2088         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2089         hdr->lun = task->lun;
2090         hdr->rtt = task->hdr_itt;
2091         hdr->refcmdsn = task->cmdsn;
2092 }
2093
2094 int iscsi_eh_abort(struct scsi_cmnd *sc)
2095 {
2096         struct iscsi_cls_session *cls_session;
2097         struct iscsi_session *session;
2098         struct iscsi_conn *conn;
2099         struct iscsi_task *task;
2100         struct iscsi_tm *hdr;
2101         int rc, age;
2102
2103         cls_session = starget_to_session(scsi_target(sc->device));
2104         session = cls_session->dd_data;
2105
2106         ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
2107
2108         mutex_lock(&session->eh_mutex);
2109         spin_lock_bh(&session->lock);
2110         /*
2111          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
2112          * got the command.
2113          */
2114         if (!sc->SCp.ptr) {
2115                 ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
2116                                       "it completed.\n");
2117                 spin_unlock_bh(&session->lock);
2118                 mutex_unlock(&session->eh_mutex);
2119                 return SUCCESS;
2120         }
2121
2122         /*
2123          * If we are not logged in or we have started a new session
2124          * then let the host reset code handle this
2125          */
2126         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
2127             sc->SCp.phase != session->age) {
2128                 spin_unlock_bh(&session->lock);
2129                 mutex_unlock(&session->eh_mutex);
2130                 ISCSI_DBG_EH(session, "failing abort due to dropped "
2131                                   "session.\n");
2132                 return FAILED;
2133         }
2134
2135         conn = session->leadconn;
2136         conn->eh_abort_cnt++;
2137         age = session->age;
2138
2139         task = (struct iscsi_task *)sc->SCp.ptr;
2140         ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
2141                      sc, task->itt);
2142
2143         /* task completed before time out */
2144         if (!task->sc) {
2145                 ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
2146                 goto success;
2147         }
2148
2149         if (task->state == ISCSI_TASK_PENDING) {
2150                 fail_scsi_task(task, DID_ABORT);
2151                 goto success;
2152         }
2153
2154         /* only have one tmf outstanding at a time */
2155         if (conn->tmf_state != TMF_INITIAL)
2156                 goto failed;
2157         conn->tmf_state = TMF_QUEUED;
2158
2159         hdr = &conn->tmhdr;
2160         iscsi_prep_abort_task_pdu(task, hdr);
2161
2162         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
2163                 rc = FAILED;
2164                 goto failed;
2165         }
2166
2167         switch (conn->tmf_state) {
2168         case TMF_SUCCESS:
2169                 spin_unlock_bh(&session->lock);
2170                 /*
2171                  * stop tx side incase the target had sent a abort rsp but
2172                  * the initiator was still writing out data.
2173                  */
2174                 iscsi_suspend_tx(conn);
2175                 /*
2176                  * we do not stop the recv side because targets have been
2177                  * good and have never sent us a successful tmf response
2178                  * then sent more data for the cmd.
2179                  */
2180                 spin_lock_bh(&session->lock);
2181                 fail_scsi_task(task, DID_ABORT);
2182                 conn->tmf_state = TMF_INITIAL;
2183                 memset(hdr, 0, sizeof(*hdr));
2184                 spin_unlock_bh(&session->lock);
2185                 iscsi_start_tx(conn);
2186                 goto success_unlocked;
2187         case TMF_TIMEDOUT:
2188                 spin_unlock_bh(&session->lock);
2189                 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2190                 goto failed_unlocked;
2191         case TMF_NOT_FOUND:
2192                 if (!sc->SCp.ptr) {
2193                         conn->tmf_state = TMF_INITIAL;
2194                         memset(hdr, 0, sizeof(*hdr));
2195                         /* task completed before tmf abort response */
2196                         ISCSI_DBG_EH(session, "sc completed while abort in "
2197                                               "progress\n");
2198                         goto success;
2199                 }
2200                 /* fall through */
2201         default:
2202                 conn->tmf_state = TMF_INITIAL;
2203                 goto failed;
2204         }
2205
2206 success:
2207         spin_unlock_bh(&session->lock);
2208 success_unlocked:
2209         ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
2210                      sc, task->itt);
2211         mutex_unlock(&session->eh_mutex);
2212         return SUCCESS;
2213
2214 failed:
2215         spin_unlock_bh(&session->lock);
2216 failed_unlocked:
2217         ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
2218                      task ? task->itt : 0);
2219         mutex_unlock(&session->eh_mutex);
2220         return FAILED;
2221 }
2222 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
2223
2224 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2225 {
2226         memset(hdr, 0, sizeof(*hdr));
2227         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2228         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2229         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2230         int_to_scsilun(sc->device->lun, &hdr->lun);
2231         hdr->rtt = RESERVED_ITT;
2232 }
2233
2234 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
2235 {
2236         struct iscsi_cls_session *cls_session;
2237         struct iscsi_session *session;
2238         struct iscsi_conn *conn;
2239         struct iscsi_tm *hdr;
2240         int rc = FAILED;
2241
2242         cls_session = starget_to_session(scsi_target(sc->device));
2243         session = cls_session->dd_data;
2244
2245         ISCSI_DBG_EH(session, "LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
2246
2247         mutex_lock(&session->eh_mutex);
2248         spin_lock_bh(&session->lock);
2249         /*
2250          * Just check if we are not logged in. We cannot check for
2251          * the phase because the reset could come from a ioctl.
2252          */
2253         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2254                 goto unlock;
2255         conn = session->leadconn;
2256
2257         /* only have one tmf outstanding at a time */
2258         if (conn->tmf_state != TMF_INITIAL)
2259                 goto unlock;
2260         conn->tmf_state = TMF_QUEUED;
2261
2262         hdr = &conn->tmhdr;
2263         iscsi_prep_lun_reset_pdu(sc, hdr);
2264
2265         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2266                                     session->lu_reset_timeout)) {
2267                 rc = FAILED;
2268                 goto unlock;
2269         }
2270
2271         switch (conn->tmf_state) {
2272         case TMF_SUCCESS:
2273                 break;
2274         case TMF_TIMEDOUT:
2275                 spin_unlock_bh(&session->lock);
2276                 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2277                 goto done;
2278         default:
2279                 conn->tmf_state = TMF_INITIAL;
2280                 goto unlock;
2281         }
2282
2283         rc = SUCCESS;
2284         spin_unlock_bh(&session->lock);
2285
2286         iscsi_suspend_tx(conn);
2287
2288         spin_lock_bh(&session->lock);
2289         memset(hdr, 0, sizeof(*hdr));
2290         fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
2291         conn->tmf_state = TMF_INITIAL;
2292         spin_unlock_bh(&session->lock);
2293
2294         iscsi_start_tx(conn);
2295         goto done;
2296
2297 unlock:
2298         spin_unlock_bh(&session->lock);
2299 done:
2300         ISCSI_DBG_EH(session, "dev reset result = %s\n",
2301                      rc == SUCCESS ? "SUCCESS" : "FAILED");
2302         mutex_unlock(&session->eh_mutex);
2303         return rc;
2304 }
2305 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
2306
2307 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
2308 {
2309         struct iscsi_session *session = cls_session->dd_data;
2310
2311         spin_lock_bh(&session->lock);
2312         if (session->state != ISCSI_STATE_LOGGED_IN) {
2313                 session->state = ISCSI_STATE_RECOVERY_FAILED;
2314                 if (session->leadconn)
2315                         wake_up(&session->leadconn->ehwait);
2316         }
2317         spin_unlock_bh(&session->lock);
2318 }
2319 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
2320
2321 /**
2322  * iscsi_eh_session_reset - drop session and attempt relogin
2323  * @sc: scsi command
2324  *
2325  * This function will wait for a relogin, session termination from
2326  * userspace, or a recovery/replacement timeout.
2327  */
2328 int iscsi_eh_session_reset(struct scsi_cmnd *sc)
2329 {
2330         struct iscsi_cls_session *cls_session;
2331         struct iscsi_session *session;
2332         struct iscsi_conn *conn;
2333
2334         cls_session = starget_to_session(scsi_target(sc->device));
2335         session = cls_session->dd_data;
2336         conn = session->leadconn;
2337
2338         mutex_lock(&session->eh_mutex);
2339         spin_lock_bh(&session->lock);
2340         if (session->state == ISCSI_STATE_TERMINATE) {
2341 failed:
2342                 ISCSI_DBG_EH(session,
2343                              "failing session reset: Could not log back into "
2344                              "%s, %s [age %d]\n", session->targetname,
2345                              conn->persistent_address, session->age);
2346                 spin_unlock_bh(&session->lock);
2347                 mutex_unlock(&session->eh_mutex);
2348                 return FAILED;
2349         }
2350
2351         spin_unlock_bh(&session->lock);
2352         mutex_unlock(&session->eh_mutex);
2353         /*
2354          * we drop the lock here but the leadconn cannot be destoyed while
2355          * we are in the scsi eh
2356          */
2357         iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2358
2359         ISCSI_DBG_EH(session, "wait for relogin\n");
2360         wait_event_interruptible(conn->ehwait,
2361                                  session->state == ISCSI_STATE_TERMINATE ||
2362                                  session->state == ISCSI_STATE_LOGGED_IN ||
2363                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
2364         if (signal_pending(current))
2365                 flush_signals(current);
2366
2367         mutex_lock(&session->eh_mutex);
2368         spin_lock_bh(&session->lock);
2369         if (session->state == ISCSI_STATE_LOGGED_IN) {
2370                 ISCSI_DBG_EH(session,
2371                              "session reset succeeded for %s,%s\n",
2372                              session->targetname, conn->persistent_address);
2373         } else
2374                 goto failed;
2375         spin_unlock_bh(&session->lock);
2376         mutex_unlock(&session->eh_mutex);
2377         return SUCCESS;
2378 }
2379 EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
2380
2381 static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2382 {
2383         memset(hdr, 0, sizeof(*hdr));
2384         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2385         hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2386         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2387         hdr->rtt = RESERVED_ITT;
2388 }
2389
2390 /**
2391  * iscsi_eh_target_reset - reset target
2392  * @sc: scsi command
2393  *
2394  * This will attempt to send a warm target reset.
2395  */
2396 int iscsi_eh_target_reset(struct scsi_cmnd *sc)
2397 {
2398         struct iscsi_cls_session *cls_session;
2399         struct iscsi_session *session;
2400         struct iscsi_conn *conn;
2401         struct iscsi_tm *hdr;
2402         int rc = FAILED;
2403
2404         cls_session = starget_to_session(scsi_target(sc->device));
2405         session = cls_session->dd_data;
2406
2407         ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
2408                      session->targetname);
2409
2410         mutex_lock(&session->eh_mutex);
2411         spin_lock_bh(&session->lock);
2412         /*
2413          * Just check if we are not logged in. We cannot check for
2414          * the phase because the reset could come from a ioctl.
2415          */
2416         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2417                 goto unlock;
2418         conn = session->leadconn;
2419
2420         /* only have one tmf outstanding at a time */
2421         if (conn->tmf_state != TMF_INITIAL)
2422                 goto unlock;
2423         conn->tmf_state = TMF_QUEUED;
2424
2425         hdr = &conn->tmhdr;
2426         iscsi_prep_tgt_reset_pdu(sc, hdr);
2427
2428         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2429                                     session->tgt_reset_timeout)) {
2430                 rc = FAILED;
2431                 goto unlock;
2432         }
2433
2434         switch (conn->tmf_state) {
2435         case TMF_SUCCESS:
2436                 break;
2437         case TMF_TIMEDOUT:
2438                 spin_unlock_bh(&session->lock);
2439                 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2440                 goto done;
2441         default:
2442                 conn->tmf_state = TMF_INITIAL;
2443                 goto unlock;
2444         }
2445
2446         rc = SUCCESS;
2447         spin_unlock_bh(&session->lock);
2448
2449         iscsi_suspend_tx(conn);
2450
2451         spin_lock_bh(&session->lock);
2452         memset(hdr, 0, sizeof(*hdr));
2453         fail_scsi_tasks(conn, -1, DID_ERROR);
2454         conn->tmf_state = TMF_INITIAL;
2455         spin_unlock_bh(&session->lock);
2456
2457         iscsi_start_tx(conn);
2458         goto done;
2459
2460 unlock:
2461         spin_unlock_bh(&session->lock);
2462 done:
2463         ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
2464                      rc == SUCCESS ? "SUCCESS" : "FAILED");
2465         mutex_unlock(&session->eh_mutex);
2466         return rc;
2467 }
2468 EXPORT_SYMBOL_GPL(iscsi_eh_target_reset);
2469
2470 /**
2471  * iscsi_eh_recover_target - reset target and possibly the session
2472  * @sc: scsi command
2473  *
2474  * This will attempt to send a warm target reset. If that fails,
2475  * we will escalate to ERL0 session recovery.
2476  */
2477 int iscsi_eh_recover_target(struct scsi_cmnd *sc)
2478 {
2479         int rc;
2480
2481         rc = iscsi_eh_target_reset(sc);
2482         if (rc == FAILED)
2483                 rc = iscsi_eh_session_reset(sc);
2484         return rc;
2485 }
2486 EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
2487
2488 /*
2489  * Pre-allocate a pool of @max items of @item_size. By default, the pool
2490  * should be accessed via kfifo_{get,put} on q->queue.
2491  * Optionally, the caller can obtain the array of object pointers
2492  * by passing in a non-NULL @items pointer
2493  */
2494 int
2495 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
2496 {
2497         int i, num_arrays = 1;
2498
2499         memset(q, 0, sizeof(*q));
2500
2501         q->max = max;
2502
2503         /* If the user passed an items pointer, he wants a copy of
2504          * the array. */
2505         if (items)
2506                 num_arrays++;
2507         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
2508         if (q->pool == NULL)
2509                 return -ENOMEM;
2510
2511         kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
2512
2513         for (i = 0; i < max; i++) {
2514                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
2515                 if (q->pool[i] == NULL) {
2516                         q->max = i;
2517                         goto enomem;
2518                 }
2519                 kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
2520         }
2521
2522         if (items) {
2523                 *items = q->pool + max;
2524                 memcpy(*items, q->pool, max * sizeof(void *));
2525         }
2526
2527         return 0;
2528
2529 enomem:
2530         iscsi_pool_free(q);
2531         return -ENOMEM;
2532 }
2533 EXPORT_SYMBOL_GPL(iscsi_pool_init);
2534
2535 void iscsi_pool_free(struct iscsi_pool *q)
2536 {
2537         int i;
2538
2539         for (i = 0; i < q->max; i++)
2540                 kfree(q->pool[i]);
2541         kfree(q->pool);
2542 }
2543 EXPORT_SYMBOL_GPL(iscsi_pool_free);
2544
2545 /**
2546  * iscsi_host_add - add host to system
2547  * @shost: scsi host
2548  * @pdev: parent device
2549  *
2550  * This should be called by partial offload and software iscsi drivers
2551  * to add a host to the system.
2552  */
2553 int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
2554 {
2555         if (!shost->can_queue)
2556                 shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
2557
2558         if (!shost->cmd_per_lun)
2559                 shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
2560
2561         if (!shost->transportt->eh_timed_out)
2562                 shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
2563         return scsi_add_host(shost, pdev);
2564 }
2565 EXPORT_SYMBOL_GPL(iscsi_host_add);
2566
2567 /**
2568  * iscsi_host_alloc - allocate a host and driver data
2569  * @sht: scsi host template
2570  * @dd_data_size: driver host data size
2571  * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
2572  *
2573  * This should be called by partial offload and software iscsi drivers.
2574  * To access the driver specific memory use the iscsi_host_priv() macro.
2575  */
2576 struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
2577                                    int dd_data_size, bool xmit_can_sleep)
2578 {
2579         struct Scsi_Host *shost;
2580         struct iscsi_host *ihost;
2581
2582         shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
2583         if (!shost)
2584                 return NULL;
2585         ihost = shost_priv(shost);
2586
2587         if (xmit_can_sleep) {
2588                 snprintf(ihost->workq_name, sizeof(ihost->workq_name),
2589                         "iscsi_q_%d", shost->host_no);
2590                 ihost->workq = create_singlethread_workqueue(ihost->workq_name);
2591                 if (!ihost->workq)
2592                         goto free_host;
2593         }
2594
2595         spin_lock_init(&ihost->lock);
2596         ihost->state = ISCSI_HOST_SETUP;
2597         ihost->num_sessions = 0;
2598         init_waitqueue_head(&ihost->session_removal_wq);
2599         return shost;
2600
2601 free_host:
2602         scsi_host_put(shost);
2603         return NULL;
2604 }
2605 EXPORT_SYMBOL_GPL(iscsi_host_alloc);
2606
2607 static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
2608 {
2609         iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
2610 }
2611
2612 /**
2613  * iscsi_host_remove - remove host and sessions
2614  * @shost: scsi host
2615  *
2616  * If there are any sessions left, this will initiate the removal and wait
2617  * for the completion.
2618  */
2619 void iscsi_host_remove(struct Scsi_Host *shost)
2620 {
2621         struct iscsi_host *ihost = shost_priv(shost);
2622         unsigned long flags;
2623
2624         spin_lock_irqsave(&ihost->lock, flags);
2625         ihost->state = ISCSI_HOST_REMOVED;
2626         spin_unlock_irqrestore(&ihost->lock, flags);
2627
2628         iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
2629         wait_event_interruptible(ihost->session_removal_wq,
2630                                  ihost->num_sessions == 0);
2631         if (signal_pending(current))
2632                 flush_signals(current);
2633
2634         scsi_remove_host(shost);
2635         if (ihost->workq)
2636                 destroy_workqueue(ihost->workq);
2637 }
2638 EXPORT_SYMBOL_GPL(iscsi_host_remove);
2639
2640 void iscsi_host_free(struct Scsi_Host *shost)
2641 {
2642         struct iscsi_host *ihost = shost_priv(shost);
2643
2644         kfree(ihost->netdev);
2645         kfree(ihost->hwaddress);
2646         kfree(ihost->initiatorname);
2647         scsi_host_put(shost);
2648 }
2649 EXPORT_SYMBOL_GPL(iscsi_host_free);
2650
2651 static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
2652 {
2653         struct iscsi_host *ihost = shost_priv(shost);
2654         unsigned long flags;
2655
2656         shost = scsi_host_get(shost);
2657         if (!shost) {
2658                 printk(KERN_ERR "Invalid state. Cannot notify host removal "
2659                       "of session teardown event because host already "
2660                       "removed.\n");
2661                 return;
2662         }
2663
2664         spin_lock_irqsave(&ihost->lock, flags);
2665         ihost->num_sessions--;
2666         if (ihost->num_sessions == 0)
2667                 wake_up(&ihost->session_removal_wq);
2668         spin_unlock_irqrestore(&ihost->lock, flags);
2669         scsi_host_put(shost);
2670 }
2671
2672 /**
2673  * iscsi_session_setup - create iscsi cls session and host and session
2674  * @iscsit: iscsi transport template
2675  * @shost: scsi host
2676  * @cmds_max: session can queue
2677  * @cmd_task_size: LLD task private data size
2678  * @initial_cmdsn: initial CmdSN
2679  *
2680  * This can be used by software iscsi_transports that allocate
2681  * a session per scsi host.
2682  *
2683  * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
2684  * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
2685  * for nop handling and login/logout requests.
2686  */
2687 struct iscsi_cls_session *
2688 iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
2689                     uint16_t cmds_max, int dd_size, int cmd_task_size,
2690                     uint32_t initial_cmdsn, unsigned int id)
2691 {
2692         struct iscsi_host *ihost = shost_priv(shost);
2693         struct iscsi_session *session;
2694         struct iscsi_cls_session *cls_session;
2695         int cmd_i, scsi_cmds, total_cmds = cmds_max;
2696         unsigned long flags;
2697
2698         spin_lock_irqsave(&ihost->lock, flags);
2699         if (ihost->state == ISCSI_HOST_REMOVED) {
2700                 spin_unlock_irqrestore(&ihost->lock, flags);
2701                 return NULL;
2702         }
2703         ihost->num_sessions++;
2704         spin_unlock_irqrestore(&ihost->lock, flags);
2705
2706         if (!total_cmds)
2707                 total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
2708         /*
2709          * The iscsi layer needs some tasks for nop handling and tmfs,
2710          * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
2711          * + 1 command for scsi IO.
2712          */
2713         if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2714                 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2715                        "must be a power of two that is at least %d.\n",
2716                        total_cmds, ISCSI_TOTAL_CMDS_MIN);
2717                 goto dec_session_count;
2718         }
2719
2720         if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
2721                 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2722                        "must be a power of 2 less than or equal to %d.\n",
2723                        cmds_max, ISCSI_TOTAL_CMDS_MAX);
2724                 total_cmds = ISCSI_TOTAL_CMDS_MAX;
2725         }
2726
2727         if (!is_power_of_2(total_cmds)) {
2728                 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2729                        "must be a power of 2.\n", total_cmds);
2730                 total_cmds = rounddown_pow_of_two(total_cmds);
2731                 if (total_cmds < ISCSI_TOTAL_CMDS_MIN)
2732                         return NULL;
2733                 printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n",
2734                        total_cmds);
2735         }
2736         scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
2737
2738         cls_session = iscsi_alloc_session(shost, iscsit,
2739                                           sizeof(struct iscsi_session) +
2740                                           dd_size);
2741         if (!cls_session)
2742                 goto dec_session_count;
2743         session = cls_session->dd_data;
2744         session->cls_session = cls_session;
2745         session->host = shost;
2746         session->state = ISCSI_STATE_FREE;
2747         session->fast_abort = 1;
2748         session->tgt_reset_timeout = 30;
2749         session->lu_reset_timeout = 15;
2750         session->abort_timeout = 10;
2751         session->scsi_cmds_max = scsi_cmds;
2752         session->cmds_max = total_cmds;
2753         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
2754         session->exp_cmdsn = initial_cmdsn + 1;
2755         session->max_cmdsn = initial_cmdsn + 1;
2756         session->max_r2t = 1;
2757         session->tt = iscsit;
2758         session->dd_data = cls_session->dd_data + sizeof(*session);
2759         mutex_init(&session->eh_mutex);
2760         spin_lock_init(&session->lock);
2761
2762         /* initialize SCSI PDU commands pool */
2763         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
2764                             (void***)&session->cmds,
2765                             cmd_task_size + sizeof(struct iscsi_task)))
2766                 goto cmdpool_alloc_fail;
2767
2768         /* pre-format cmds pool with ITT */
2769         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2770                 struct iscsi_task *task = session->cmds[cmd_i];
2771
2772                 if (cmd_task_size)
2773                         task->dd_data = &task[1];
2774                 task->itt = cmd_i;
2775                 task->state = ISCSI_TASK_FREE;
2776                 INIT_LIST_HEAD(&task->running);
2777         }
2778
2779         if (!try_module_get(iscsit->owner))
2780                 goto module_get_fail;
2781
2782         if (iscsi_add_session(cls_session, id))
2783                 goto cls_session_fail;
2784
2785         return cls_session;
2786
2787 cls_session_fail:
2788         module_put(iscsit->owner);
2789 module_get_fail:
2790         iscsi_pool_free(&session->cmdpool);
2791 cmdpool_alloc_fail:
2792         iscsi_free_session(cls_session);
2793 dec_session_count:
2794         iscsi_host_dec_session_cnt(shost);
2795         return NULL;
2796 }
2797 EXPORT_SYMBOL_GPL(iscsi_session_setup);
2798
2799 /**
2800  * iscsi_session_teardown - destroy session, host, and cls_session
2801  * @cls_session: iscsi session
2802  *
2803  * The driver must have called iscsi_remove_session before
2804  * calling this.
2805  */
2806 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
2807 {
2808         struct iscsi_session *session = cls_session->dd_data;
2809         struct module *owner = cls_session->transport->owner;
2810         struct Scsi_Host *shost = session->host;
2811
2812         iscsi_pool_free(&session->cmdpool);
2813
2814         kfree(session->password);
2815         kfree(session->password_in);
2816         kfree(session->username);
2817         kfree(session->username_in);
2818         kfree(session->targetname);
2819         kfree(session->targetalias);
2820         kfree(session->initiatorname);
2821         kfree(session->boot_root);
2822         kfree(session->boot_nic);
2823         kfree(session->boot_target);
2824         kfree(session->ifacename);
2825         kfree(session->portal_type);
2826         kfree(session->discovery_parent_type);
2827
2828         iscsi_destroy_session(cls_session);
2829         iscsi_host_dec_session_cnt(shost);
2830         module_put(owner);
2831 }
2832 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
2833
2834 /**
2835  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
2836  * @cls_session: iscsi_cls_session
2837  * @dd_size: private driver data size
2838  * @conn_idx: cid
2839  */
2840 struct iscsi_cls_conn *
2841 iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
2842                  uint32_t conn_idx)
2843 {
2844         struct iscsi_session *session = cls_session->dd_data;
2845         struct iscsi_conn *conn;
2846         struct iscsi_cls_conn *cls_conn;
2847         char *data;
2848
2849         cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
2850                                      conn_idx);
2851         if (!cls_conn)
2852                 return NULL;
2853         conn = cls_conn->dd_data;
2854         memset(conn, 0, sizeof(*conn) + dd_size);
2855
2856         conn->dd_data = cls_conn->dd_data + sizeof(*conn);
2857         conn->session = session;
2858         conn->cls_conn = cls_conn;
2859         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
2860         conn->id = conn_idx;
2861         conn->exp_statsn = 0;
2862         conn->tmf_state = TMF_INITIAL;
2863
2864         init_timer(&conn->transport_timer);
2865         conn->transport_timer.data = (unsigned long)conn;
2866         conn->transport_timer.function = iscsi_check_transport_timeouts;
2867
2868         INIT_LIST_HEAD(&conn->mgmtqueue);
2869         INIT_LIST_HEAD(&conn->cmdqueue);
2870         INIT_LIST_HEAD(&conn->requeue);
2871         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
2872
2873         /* allocate login_task used for the login/text sequences */
2874         spin_lock_bh(&session->lock);
2875         if (!kfifo_out(&session->cmdpool.queue,
2876                          (void*)&conn->login_task,
2877                          sizeof(void*))) {
2878                 spin_unlock_bh(&session->lock);
2879                 goto login_task_alloc_fail;
2880         }
2881         spin_unlock_bh(&session->lock);
2882
2883         data = (char *) __get_free_pages(GFP_KERNEL,
2884                                          get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2885         if (!data)
2886                 goto login_task_data_alloc_fail;
2887         conn->login_task->data = conn->data = data;
2888
2889         init_timer(&conn->tmf_timer);
2890         init_waitqueue_head(&conn->ehwait);
2891
2892         return cls_conn;
2893
2894 login_task_data_alloc_fail:
2895         kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2896                     sizeof(void*));
2897 login_task_alloc_fail:
2898         iscsi_destroy_conn(cls_conn);
2899         return NULL;
2900 }
2901 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2902
2903 /**
2904  * iscsi_conn_teardown - teardown iscsi connection
2905  * cls_conn: iscsi class connection
2906  *
2907  * TODO: we may need to make this into a two step process
2908  * like scsi-mls remove + put host
2909  */
2910 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2911 {
2912         struct iscsi_conn *conn = cls_conn->dd_data;
2913         struct iscsi_session *session = conn->session;
2914         unsigned long flags;
2915
2916         del_timer_sync(&conn->transport_timer);
2917
2918         spin_lock_bh(&session->lock);
2919         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2920         if (session->leadconn == conn) {
2921                 /*
2922                  * leading connection? then give up on recovery.
2923                  */
2924                 session->state = ISCSI_STATE_TERMINATE;
2925                 wake_up(&conn->ehwait);
2926         }
2927         spin_unlock_bh(&session->lock);
2928
2929         /*
2930          * Block until all in-progress commands for this connection
2931          * time out or fail.
2932          */
2933         for (;;) {
2934                 spin_lock_irqsave(session->host->host_lock, flags);
2935                 if (!session->host->host_busy) { /* OK for ERL == 0 */
2936                         spin_unlock_irqrestore(session->host->host_lock, flags);
2937                         break;
2938                 }
2939                 spin_unlock_irqrestore(session->host->host_lock, flags);
2940                 msleep_interruptible(500);
2941                 iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
2942                                   "host_busy %d host_failed %d\n",
2943                                   session->host->host_busy,
2944                                   session->host->host_failed);
2945                 /*
2946                  * force eh_abort() to unblock
2947                  */
2948                 wake_up(&conn->ehwait);
2949         }
2950
2951         /* flush queued up work because we free the connection below */
2952         iscsi_suspend_tx(conn);
2953
2954         spin_lock_bh(&session->lock);
2955         free_pages((unsigned long) conn->data,
2956                    get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2957         kfree(conn->persistent_address);
2958         kfree(conn->local_ipaddr);
2959         kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2960                     sizeof(void*));
2961         if (session->leadconn == conn)
2962                 session->leadconn = NULL;
2963         spin_unlock_bh(&session->lock);
2964
2965         iscsi_destroy_conn(cls_conn);
2966 }
2967 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
2968
2969 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
2970 {
2971         struct iscsi_conn *conn = cls_conn->dd_data;
2972         struct iscsi_session *session = conn->session;
2973
2974         if (!session) {
2975                 iscsi_conn_printk(KERN_ERR, conn,
2976                                   "can't start unbound connection\n");
2977                 return -EPERM;
2978         }
2979
2980         if ((session->imm_data_en || !session->initial_r2t_en) &&
2981              session->first_burst > session->max_burst) {
2982                 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
2983                                   "first_burst %d max_burst %d\n",
2984                                   session->first_burst, session->max_burst);
2985                 return -EINVAL;
2986         }
2987
2988         if (conn->ping_timeout && !conn->recv_timeout) {
2989                 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
2990                                   "zero. Using 5 seconds\n.");
2991                 conn->recv_timeout = 5;
2992         }
2993
2994         if (conn->recv_timeout && !conn->ping_timeout) {
2995                 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
2996                                   "zero. Using 5 seconds.\n");
2997                 conn->ping_timeout = 5;
2998         }
2999
3000         spin_lock_bh(&session->lock);
3001         conn->c_stage = ISCSI_CONN_STARTED;
3002         session->state = ISCSI_STATE_LOGGED_IN;
3003         session->queued_cmdsn = session->cmdsn;
3004
3005         conn->last_recv = jiffies;
3006         conn->last_ping = jiffies;
3007         if (conn->recv_timeout && conn->ping_timeout)
3008                 mod_timer(&conn->transport_timer,
3009                           jiffies + (conn->recv_timeout * HZ));
3010
3011         switch(conn->stop_stage) {
3012         case STOP_CONN_RECOVER:
3013                 /*
3014                  * unblock eh_abort() if it is blocked. re-try all
3015                  * commands after successful recovery
3016                  */
3017                 conn->stop_stage = 0;
3018                 conn->tmf_state = TMF_INITIAL;
3019                 session->age++;
3020                 if (session->age == 16)
3021                         session->age = 0;
3022                 break;
3023         case STOP_CONN_TERM:
3024                 conn->stop_stage = 0;
3025                 break;
3026         default:
3027                 break;
3028         }
3029         spin_unlock_bh(&session->lock);
3030
3031         iscsi_unblock_session(session->cls_session);
3032         wake_up(&conn->ehwait);
3033         return 0;
3034 }
3035 EXPORT_SYMBOL_GPL(iscsi_conn_start);
3036
3037 static void
3038 fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
3039 {
3040         struct iscsi_task *task;
3041         int i, state;
3042
3043         for (i = 0; i < conn->session->cmds_max; i++) {
3044                 task = conn->session->cmds[i];
3045                 if (task->sc)
3046                         continue;
3047
3048                 if (task->state == ISCSI_TASK_FREE)
3049                         continue;
3050
3051                 ISCSI_DBG_SESSION(conn->session,
3052                                   "failing mgmt itt 0x%x state %d\n",
3053                                   task->itt, task->state);
3054                 state = ISCSI_TASK_ABRT_SESS_RECOV;
3055                 if (task->state == ISCSI_TASK_PENDING)
3056                         state = ISCSI_TASK_COMPLETED;
3057                 iscsi_complete_task(task, state);
3058
3059         }
3060 }
3061
3062 static void iscsi_start_session_recovery(struct iscsi_session *session,
3063                                          struct iscsi_conn *conn, int flag)
3064 {
3065         int old_stop_stage;
3066
3067         mutex_lock(&session->eh_mutex);
3068         spin_lock_bh(&session->lock);
3069         if (conn->stop_stage == STOP_CONN_TERM) {
3070                 spin_unlock_bh(&session->lock);
3071                 mutex_unlock(&session->eh_mutex);
3072                 return;
3073         }
3074
3075         /*
3076          * When this is called for the in_login state, we only want to clean
3077          * up the login task and connection. We do not need to block and set
3078          * the recovery state again
3079          */
3080         if (flag == STOP_CONN_TERM)
3081                 session->state = ISCSI_STATE_TERMINATE;
3082         else if (conn->stop_stage != STOP_CONN_RECOVER)
3083                 session->state = ISCSI_STATE_IN_RECOVERY;
3084
3085         old_stop_stage = conn->stop_stage;
3086         conn->stop_stage = flag;
3087         spin_unlock_bh(&session->lock);
3088
3089         del_timer_sync(&conn->transport_timer);
3090         iscsi_suspend_tx(conn);
3091
3092         spin_lock_bh(&session->lock);
3093         conn->c_stage = ISCSI_CONN_STOPPED;
3094         spin_unlock_bh(&session->lock);
3095
3096         /*
3097          * for connection level recovery we should not calculate
3098          * header digest. conn->hdr_size used for optimization
3099          * in hdr_extract() and will be re-negotiated at
3100          * set_param() time.
3101          */
3102         if (flag == STOP_CONN_RECOVER) {
3103                 conn->hdrdgst_en = 0;
3104                 conn->datadgst_en = 0;
3105                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
3106                     old_stop_stage != STOP_CONN_RECOVER) {
3107                         ISCSI_DBG_SESSION(session, "blocking session\n");
3108                         iscsi_block_session(session->cls_session);
3109                 }
3110         }
3111
3112         /*
3113          * flush queues.
3114          */
3115         spin_lock_bh(&session->lock);
3116         fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
3117         fail_mgmt_tasks(session, conn);
3118         memset(&conn->tmhdr, 0, sizeof(conn->tmhdr));
3119         spin_unlock_bh(&session->lock);
3120         mutex_unlock(&session->eh_mutex);
3121 }
3122
3123 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
3124 {
3125         struct iscsi_conn *conn = cls_conn->dd_data;
3126         struct iscsi_session *session = conn->session;
3127
3128         switch (flag) {
3129         case STOP_CONN_RECOVER:
3130         case STOP_CONN_TERM:
3131                 iscsi_start_session_recovery(session, conn, flag);
3132                 break;
3133         default:
3134                 iscsi_conn_printk(KERN_ERR, conn,
3135                                   "invalid stop flag %d\n", flag);
3136         }
3137 }
3138 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
3139
3140 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
3141                     struct iscsi_cls_conn *cls_conn, int is_leading)
3142 {
3143         struct iscsi_session *session = cls_session->dd_data;
3144         struct iscsi_conn *conn = cls_conn->dd_data;
3145
3146         spin_lock_bh(&session->lock);
3147         if (is_leading)
3148                 session->leadconn = conn;
3149         spin_unlock_bh(&session->lock);
3150
3151         /*
3152          * Unblock xmitworker(), Login Phase will pass through.
3153          */
3154         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
3155         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
3156         return 0;
3157 }
3158 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
3159
3160 int iscsi_switch_str_param(char **param, char *new_val_buf)
3161 {
3162         char *new_val;
3163
3164         if (*param) {
3165                 if (!strcmp(*param, new_val_buf))
3166                         return 0;
3167         }
3168
3169         new_val = kstrdup(new_val_buf, GFP_NOIO);
3170         if (!new_val)
3171                 return -ENOMEM;
3172
3173         kfree(*param);
3174         *param = new_val;
3175         return 0;
3176 }
3177 EXPORT_SYMBOL_GPL(iscsi_switch_str_param);
3178
3179 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
3180                     enum iscsi_param param, char *buf, int buflen)
3181 {
3182         struct iscsi_conn *conn = cls_conn->dd_data;
3183         struct iscsi_session *session = conn->session;
3184         int val;
3185
3186         switch(param) {
3187         case ISCSI_PARAM_FAST_ABORT:
3188                 sscanf(buf, "%d", &session->fast_abort);
3189                 break;
3190         case ISCSI_PARAM_ABORT_TMO:
3191                 sscanf(buf, "%d", &session->abort_timeout);
3192                 break;
3193         case ISCSI_PARAM_LU_RESET_TMO:
3194                 sscanf(buf, "%d", &session->lu_reset_timeout);
3195                 break;
3196         case ISCSI_PARAM_TGT_RESET_TMO:
3197                 sscanf(buf, "%d", &session->tgt_reset_timeout);
3198                 break;
3199         case ISCSI_PARAM_PING_TMO:
3200                 sscanf(buf, "%d", &conn->ping_timeout);
3201                 break;
3202         case ISCSI_PARAM_RECV_TMO:
3203                 sscanf(buf, "%d", &conn->recv_timeout);
3204                 break;
3205         case ISCSI_PARAM_MAX_RECV_DLENGTH:
3206                 sscanf(buf, "%d", &conn->max_recv_dlength);
3207                 break;
3208         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3209                 sscanf(buf, "%d", &conn->max_xmit_dlength);
3210                 break;
3211         case ISCSI_PARAM_HDRDGST_EN:
3212                 sscanf(buf, "%d", &conn->hdrdgst_en);
3213                 break;
3214         case ISCSI_PARAM_DATADGST_EN:
3215                 sscanf(buf, "%d", &conn->datadgst_en);
3216                 break;
3217         case ISCSI_PARAM_INITIAL_R2T_EN:
3218                 sscanf(buf, "%d", &session->initial_r2t_en);
3219                 break;
3220         case ISCSI_PARAM_MAX_R2T:
3221                 sscanf(buf, "%hu", &session->max_r2t);
3222                 break;
3223         case ISCSI_PARAM_IMM_DATA_EN:
3224                 sscanf(buf, "%d", &session->imm_data_en);
3225                 break;
3226         case ISCSI_PARAM_FIRST_BURST:
3227                 sscanf(buf, "%d", &session->first_burst);
3228                 break;
3229         case ISCSI_PARAM_MAX_BURST:
3230                 sscanf(buf, "%d", &session->max_burst);
3231                 break;
3232         case ISCSI_PARAM_PDU_INORDER_EN:
3233                 sscanf(buf, "%d", &session->pdu_inorder_en);
3234                 break;
3235         case ISCSI_PARAM_DATASEQ_INORDER_EN:
3236                 sscanf(buf, "%d", &session->dataseq_inorder_en);
3237                 break;
3238         case ISCSI_PARAM_ERL:
3239                 sscanf(buf, "%d", &session->erl);
3240                 break;
3241         case ISCSI_PARAM_EXP_STATSN:
3242                 sscanf(buf, "%u", &conn->exp_statsn);
3243                 break;
3244         case ISCSI_PARAM_USERNAME:
3245                 return iscsi_switch_str_param(&session->username, buf);
3246         case ISCSI_PARAM_USERNAME_IN:
3247                 return iscsi_switch_str_param(&session->username_in, buf);
3248         case ISCSI_PARAM_PASSWORD:
3249                 return iscsi_switch_str_param(&session->password, buf);
3250         case ISCSI_PARAM_PASSWORD_IN:
3251                 return iscsi_switch_str_param(&session->password_in, buf);
3252         case ISCSI_PARAM_TARGET_NAME:
3253                 return iscsi_switch_str_param(&session->targetname, buf);
3254         case ISCSI_PARAM_TARGET_ALIAS:
3255                 return iscsi_switch_str_param(&session->targetalias, buf);
3256         case ISCSI_PARAM_TPGT:
3257                 sscanf(buf, "%d", &session->tpgt);
3258                 break;
3259         case ISCSI_PARAM_PERSISTENT_PORT:
3260                 sscanf(buf, "%d", &conn->persistent_port);
3261                 break;
3262         case ISCSI_PARAM_PERSISTENT_ADDRESS:
3263                 return iscsi_switch_str_param(&conn->persistent_address, buf);
3264         case ISCSI_PARAM_IFACE_NAME:
3265                 return iscsi_switch_str_param(&session->ifacename, buf);
3266         case ISCSI_PARAM_INITIATOR_NAME:
3267                 return iscsi_switch_str_param(&session->initiatorname, buf);
3268         case ISCSI_PARAM_BOOT_ROOT:
3269                 return iscsi_switch_str_param(&session->boot_root, buf);
3270         case ISCSI_PARAM_BOOT_NIC:
3271                 return iscsi_switch_str_param(&session->boot_nic, buf);
3272         case ISCSI_PARAM_BOOT_TARGET:
3273                 return iscsi_switch_str_param(&session->boot_target, buf);
3274         case ISCSI_PARAM_PORTAL_TYPE:
3275                 return iscsi_switch_str_param(&session->portal_type, buf);
3276         case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3277                 return iscsi_switch_str_param(&session->discovery_parent_type,
3278                                               buf);
3279         case ISCSI_PARAM_DISCOVERY_SESS:
3280                 sscanf(buf, "%d", &val);
3281                 session->discovery_sess = !!val;
3282                 break;
3283         case ISCSI_PARAM_LOCAL_IPADDR:
3284                 return iscsi_switch_str_param(&conn->local_ipaddr, buf);
3285         default:
3286                 return -ENOSYS;
3287         }
3288
3289         return 0;
3290 }
3291 EXPORT_SYMBOL_GPL(iscsi_set_param);
3292
3293 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
3294                             enum iscsi_param param, char *buf)
3295 {
3296         struct iscsi_session *session = cls_session->dd_data;
3297         int len;
3298
3299         switch(param) {
3300         case ISCSI_PARAM_FAST_ABORT:
3301                 len = sprintf(buf, "%d\n", session->fast_abort);
3302                 break;
3303         case ISCSI_PARAM_ABORT_TMO:
3304                 len = sprintf(buf, "%d\n", session->abort_timeout);
3305                 break;
3306         case ISCSI_PARAM_LU_RESET_TMO:
3307                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
3308                 break;
3309         case ISCSI_PARAM_TGT_RESET_TMO:
3310                 len = sprintf(buf, "%d\n", session->tgt_reset_timeout);
3311                 break;
3312         case ISCSI_PARAM_INITIAL_R2T_EN:
3313                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
3314                 break;
3315         case ISCSI_PARAM_MAX_R2T:
3316                 len = sprintf(buf, "%hu\n", session->max_r2t);
3317                 break;
3318         case ISCSI_PARAM_IMM_DATA_EN:
3319                 len = sprintf(buf, "%d\n", session->imm_data_en);
3320                 break;
3321         case ISCSI_PARAM_FIRST_BURST:
3322                 len = sprintf(buf, "%u\n", session->first_burst);
3323                 break;
3324         case ISCSI_PARAM_MAX_BURST:
3325                 len = sprintf(buf, "%u\n", session->max_burst);
3326                 break;
3327         case ISCSI_PARAM_PDU_INORDER_EN:
3328                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
3329                 break;
3330         case ISCSI_PARAM_DATASEQ_INORDER_EN:
3331                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
3332                 break;
3333         case ISCSI_PARAM_DEF_TASKMGMT_TMO:
3334                 len = sprintf(buf, "%d\n", session->def_taskmgmt_tmo);
3335                 break;
3336         case ISCSI_PARAM_ERL:
3337                 len = sprintf(buf, "%d\n", session->erl);
3338                 break;
3339         case ISCSI_PARAM_TARGET_NAME:
3340                 len = sprintf(buf, "%s\n", session->targetname);
3341                 break;
3342         case ISCSI_PARAM_TARGET_ALIAS:
3343                 len = sprintf(buf, "%s\n", session->targetalias);
3344                 break;
3345         case ISCSI_PARAM_TPGT:
3346                 len = sprintf(buf, "%d\n", session->tpgt);
3347                 break;
3348         case ISCSI_PARAM_USERNAME:
3349                 len = sprintf(buf, "%s\n", session->username);
3350                 break;
3351         case ISCSI_PARAM_USERNAME_IN:
3352                 len = sprintf(buf, "%s\n", session->username_in);
3353                 break;
3354         case ISCSI_PARAM_PASSWORD:
3355                 len = sprintf(buf, "%s\n", session->password);
3356                 break;
3357         case ISCSI_PARAM_PASSWORD_IN:
3358                 len = sprintf(buf, "%s\n", session->password_in);
3359                 break;
3360         case ISCSI_PARAM_IFACE_NAME:
3361                 len = sprintf(buf, "%s\n", session->ifacename);
3362                 break;
3363         case ISCSI_PARAM_INITIATOR_NAME:
3364                 len = sprintf(buf, "%s\n", session->initiatorname);
3365                 break;
3366         case ISCSI_PARAM_BOOT_ROOT:
3367                 len = sprintf(buf, "%s\n", session->boot_root);
3368                 break;
3369         case ISCSI_PARAM_BOOT_NIC:
3370                 len = sprintf(buf, "%s\n", session->boot_nic);
3371                 break;
3372         case ISCSI_PARAM_BOOT_TARGET:
3373                 len = sprintf(buf, "%s\n", session->boot_target);
3374                 break;
3375         case ISCSI_PARAM_AUTO_SND_TGT_DISABLE:
3376                 len = sprintf(buf, "%u\n", session->auto_snd_tgt_disable);
3377                 break;
3378         case ISCSI_PARAM_DISCOVERY_SESS:
3379                 len = sprintf(buf, "%u\n", session->discovery_sess);
3380                 break;
3381         case ISCSI_PARAM_PORTAL_TYPE:
3382                 len = sprintf(buf, "%s\n", session->portal_type);
3383                 break;
3384         case ISCSI_PARAM_CHAP_AUTH_EN:
3385                 len = sprintf(buf, "%u\n", session->chap_auth_en);
3386                 break;
3387         case ISCSI_PARAM_DISCOVERY_LOGOUT_EN:
3388                 len = sprintf(buf, "%u\n", session->discovery_logout_en);
3389                 break;
3390         case ISCSI_PARAM_BIDI_CHAP_EN:
3391                 len = sprintf(buf, "%u\n", session->bidi_chap_en);
3392                 break;
3393         case ISCSI_PARAM_DISCOVERY_AUTH_OPTIONAL:
3394                 len = sprintf(buf, "%u\n", session->discovery_auth_optional);
3395                 break;
3396         case ISCSI_PARAM_DEF_TIME2WAIT:
3397                 len = sprintf(buf, "%d\n", session->time2wait);
3398                 break;
3399         case ISCSI_PARAM_DEF_TIME2RETAIN:
3400                 len = sprintf(buf, "%d\n", session->time2retain);
3401                 break;
3402         case ISCSI_PARAM_TSID:
3403                 len = sprintf(buf, "%u\n", session->tsid);
3404                 break;
3405         case ISCSI_PARAM_ISID:
3406                 len = sprintf(buf, "%02x%02x%02x%02x%02x%02x\n",
3407                               session->isid[0], session->isid[1],
3408                               session->isid[2], session->isid[3],
3409                               session->isid[4], session->isid[5]);
3410                 break;
3411         case ISCSI_PARAM_DISCOVERY_PARENT_IDX:
3412                 len = sprintf(buf, "%u\n", session->discovery_parent_idx);
3413                 break;
3414         case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3415                 if (session->discovery_parent_type)
3416                         len = sprintf(buf, "%s\n",
3417                                       session->discovery_parent_type);
3418                 else
3419                         len = sprintf(buf, "\n");
3420                 break;
3421         default:
3422                 return -ENOSYS;
3423         }
3424
3425         return len;
3426 }
3427 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
3428
3429 int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
3430                               enum iscsi_param param, char *buf)
3431 {
3432         struct sockaddr_in6 *sin6 = NULL;
3433         struct sockaddr_in *sin = NULL;
3434         int len;
3435
3436         switch (addr->ss_family) {
3437         case AF_INET:
3438                 sin = (struct sockaddr_in *)addr;
3439                 break;
3440         case AF_INET6:
3441                 sin6 = (struct sockaddr_in6 *)addr;
3442                 break;
3443         default:
3444                 return -EINVAL;
3445         }
3446
3447         switch (param) {
3448         case ISCSI_PARAM_CONN_ADDRESS:
3449         case ISCSI_HOST_PARAM_IPADDRESS:
3450                 if (sin)
3451                         len = sprintf(buf, "%pI4\n", &sin->sin_addr.s_addr);
3452                 else
3453                         len = sprintf(buf, "%pI6\n", &sin6->sin6_addr);
3454                 break;
3455         case ISCSI_PARAM_CONN_PORT:
3456                 if (sin)
3457                         len = sprintf(buf, "%hu\n", be16_to_cpu(sin->sin_port));
3458                 else
3459                         len = sprintf(buf, "%hu\n",
3460                                       be16_to_cpu(sin6->sin6_port));
3461                 break;
3462         default:
3463                 return -EINVAL;
3464         }
3465
3466         return len;
3467 }
3468 EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param);
3469
3470 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
3471                          enum iscsi_param param, char *buf)
3472 {
3473         struct iscsi_conn *conn = cls_conn->dd_data;
3474         int len;
3475
3476         switch(param) {
3477         case ISCSI_PARAM_PING_TMO:
3478                 len = sprintf(buf, "%u\n", conn->ping_timeout);
3479                 break;
3480         case ISCSI_PARAM_RECV_TMO:
3481                 len = sprintf(buf, "%u\n", conn->recv_timeout);
3482                 break;
3483         case ISCSI_PARAM_MAX_RECV_DLENGTH:
3484                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
3485                 break;
3486         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3487                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
3488                 break;
3489         case ISCSI_PARAM_HDRDGST_EN:
3490                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
3491                 break;
3492         case ISCSI_PARAM_DATADGST_EN:
3493                 len = sprintf(buf, "%d\n", conn->datadgst_en);
3494                 break;
3495         case ISCSI_PARAM_IFMARKER_EN:
3496                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
3497                 break;
3498         case ISCSI_PARAM_OFMARKER_EN:
3499                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
3500                 break;
3501         case ISCSI_PARAM_EXP_STATSN:
3502                 len = sprintf(buf, "%u\n", conn->exp_statsn);
3503                 break;
3504         case ISCSI_PARAM_PERSISTENT_PORT:
3505                 len = sprintf(buf, "%d\n", conn->persistent_port);
3506                 break;
3507         case ISCSI_PARAM_PERSISTENT_ADDRESS:
3508                 len = sprintf(buf, "%s\n", conn->persistent_address);
3509                 break;
3510         case ISCSI_PARAM_STATSN:
3511                 len = sprintf(buf, "%u\n", conn->statsn);
3512                 break;
3513         case ISCSI_PARAM_MAX_SEGMENT_SIZE:
3514                 len = sprintf(buf, "%u\n", conn->max_segment_size);
3515                 break;
3516         case ISCSI_PARAM_KEEPALIVE_TMO:
3517                 len = sprintf(buf, "%u\n", conn->keepalive_tmo);
3518                 break;
3519         case ISCSI_PARAM_LOCAL_PORT:
3520                 len = sprintf(buf, "%u\n", conn->local_port);
3521                 break;
3522         case ISCSI_PARAM_TCP_TIMESTAMP_STAT:
3523                 len = sprintf(buf, "%u\n", conn->tcp_timestamp_stat);
3524                 break;
3525         case ISCSI_PARAM_TCP_NAGLE_DISABLE:
3526                 len = sprintf(buf, "%u\n", conn->tcp_nagle_disable);
3527                 break;
3528         case ISCSI_PARAM_TCP_WSF_DISABLE:
3529                 len = sprintf(buf, "%u\n", conn->tcp_wsf_disable);
3530                 break;
3531         case ISCSI_PARAM_TCP_TIMER_SCALE:
3532                 len = sprintf(buf, "%u\n", conn->tcp_timer_scale);
3533                 break;
3534         case ISCSI_PARAM_TCP_TIMESTAMP_EN:
3535                 len = sprintf(buf, "%u\n", conn->tcp_timestamp_en);
3536                 break;
3537         case ISCSI_PARAM_IP_FRAGMENT_DISABLE:
3538                 len = sprintf(buf, "%u\n", conn->fragment_disable);
3539                 break;
3540         case ISCSI_PARAM_IPV4_TOS:
3541                 len = sprintf(buf, "%u\n", conn->ipv4_tos);
3542                 break;
3543         case ISCSI_PARAM_IPV6_TC:
3544                 len = sprintf(buf, "%u\n", conn->ipv6_traffic_class);
3545                 break;
3546         case ISCSI_PARAM_IPV6_FLOW_LABEL:
3547                 len = sprintf(buf, "%u\n", conn->ipv6_flow_label);
3548                 break;
3549         case ISCSI_PARAM_IS_FW_ASSIGNED_IPV6:
3550                 len = sprintf(buf, "%u\n", conn->is_fw_assigned_ipv6);
3551                 break;
3552         case ISCSI_PARAM_TCP_XMIT_WSF:
3553                 len = sprintf(buf, "%u\n", conn->tcp_xmit_wsf);
3554                 break;
3555         case ISCSI_PARAM_TCP_RECV_WSF:
3556                 len = sprintf(buf, "%u\n", conn->tcp_recv_wsf);
3557                 break;
3558         case ISCSI_PARAM_LOCAL_IPADDR:
3559                 len = sprintf(buf, "%s\n", conn->local_ipaddr);
3560                 break;
3561         default:
3562                 return -ENOSYS;
3563         }
3564
3565         return len;
3566 }
3567 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
3568
3569 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3570                          char *buf)
3571 {
3572         struct iscsi_host *ihost = shost_priv(shost);
3573         int len;
3574
3575         switch (param) {
3576         case ISCSI_HOST_PARAM_NETDEV_NAME:
3577                 len = sprintf(buf, "%s\n", ihost->netdev);
3578                 break;
3579         case ISCSI_HOST_PARAM_HWADDRESS:
3580                 len = sprintf(buf, "%s\n", ihost->hwaddress);
3581                 break;
3582         case ISCSI_HOST_PARAM_INITIATOR_NAME:
3583                 len = sprintf(buf, "%s\n", ihost->initiatorname);
3584                 break;
3585         default:
3586                 return -ENOSYS;
3587         }
3588
3589         return len;
3590 }
3591 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
3592
3593 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3594                          char *buf, int buflen)
3595 {
3596         struct iscsi_host *ihost = shost_priv(shost);
3597
3598         switch (param) {
3599         case ISCSI_HOST_PARAM_NETDEV_NAME:
3600                 return iscsi_switch_str_param(&ihost->netdev, buf);
3601         case ISCSI_HOST_PARAM_HWADDRESS:
3602                 return iscsi_switch_str_param(&ihost->hwaddress, buf);
3603         case ISCSI_HOST_PARAM_INITIATOR_NAME:
3604                 return iscsi_switch_str_param(&ihost->initiatorname, buf);
3605         default:
3606                 return -ENOSYS;
3607         }
3608
3609         return 0;
3610 }
3611 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
3612
3613 MODULE_AUTHOR("Mike Christie");
3614 MODULE_DESCRIPTION("iSCSI library functions");
3615 MODULE_LICENSE("GPL");