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 <asm/unaligned.h>
  29 #include <net/tcp.h>
  30 #include <scsi/scsi_cmnd.h>
  31 #include <scsi/scsi_device.h>
  32 #include <scsi/scsi_eh.h>
  33 #include <scsi/scsi_tcq.h>
  34 #include <scsi/scsi_host.h>
  35 #include <scsi/scsi.h>
  36 #include <scsi/iscsi_proto.h>
  37 #include <scsi/scsi_transport.h>
  38 #include <scsi/scsi_transport_iscsi.h>
  39 #include <scsi/libiscsi.h>
  40
  41 struct iscsi_session *
  42 class_to_transport_session(struct iscsi_cls_session *cls_session)
  43 {
  44         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
  45         return iscsi_hostdata(shost->hostdata);
  46 }
  47 EXPORT_SYMBOL_GPL(class_to_transport_session);
  48
  49 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  50 #define SNA32_CHECK 2147483648UL
  51
  52 static int iscsi_sna_lt(u32 n1, u32 n2)
  53 {
  54         return n1 != n2 && ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  55                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  56 }
  57
  58 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  59 static int iscsi_sna_lte(u32 n1, u32 n2)
  60 {
  61         return n1 == n2 || ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  62                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  63 }
  64
  65 void
  66 iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
  67 {
  68         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
  69         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
  70
  71         /*
  72          * standard specifies this check for when to update expected and
  73          * max sequence numbers
  74          */
  75         if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
  76                 return;
  77
  78         if (exp_cmdsn != session->exp_cmdsn &&
  79             !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
  80                 session->exp_cmdsn = exp_cmdsn;
  81
  82         if (max_cmdsn != session->max_cmdsn &&
  83             !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
  84                 session->max_cmdsn = max_cmdsn;
  85                 /*
  86                  * if the window closed with IO queued, then kick the
  87                  * xmit thread
  88                  */
  89                 if (!list_empty(&session->leadconn->xmitqueue) ||
  90                     !list_empty(&session->leadconn->mgmtqueue))
  91                         scsi_queue_work(session->host,
  92                                         &session->leadconn->xmitwork);
  93         }
  94 }
  95 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
  96
  97 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
  98                                    struct iscsi_data *hdr)
  99 {
 100         struct iscsi_conn *conn = ctask->conn;
 101
 102         memset(hdr, 0, sizeof(struct iscsi_data));
 103         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
 104         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
 105         ctask->unsol_datasn++;
 106         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
 107         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
 108
 109         hdr->itt = ctask->hdr->itt;
 110         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 111         hdr->offset = cpu_to_be32(ctask->unsol_offset);
 112
 113         if (ctask->unsol_count > conn->max_xmit_dlength) {
 114                 hton24(hdr->dlength, conn->max_xmit_dlength);
 115                 ctask->data_count = conn->max_xmit_dlength;
 116                 ctask->unsol_offset += ctask->data_count;
 117                 hdr->flags = 0;
 118         } else {
 119                 hton24(hdr->dlength, ctask->unsol_count);
 120                 ctask->data_count = ctask->unsol_count;
 121                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
 122         }
 123 }
 124 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
 125
 126 static int iscsi_add_hdr(struct iscsi_cmd_task *ctask, unsigned len)
 127 {
 128         unsigned exp_len = ctask->hdr_len + len;
 129
 130         if (exp_len > ctask->hdr_max) {
 131                 WARN_ON(1);
 132                 return -EINVAL;
 133         }
 134
 135         WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
 136         ctask->hdr_len = exp_len;
 137         return 0;
 138 }
 139
 140 /**
 141  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 142  * @ctask: iscsi cmd task
 143  *
 144  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 145  * fields like dlength or final based on how much data it sends
 146  */
 147 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
 148 {
 149         struct iscsi_conn *conn = ctask->conn;
 150         struct iscsi_session *session = conn->session;
 151         struct iscsi_cmd *hdr = ctask->hdr;
 152         struct scsi_cmnd *sc = ctask->sc;
 153         unsigned hdrlength;
 154         int rc;
 155
 156         ctask->hdr_len = 0;
 157         rc = iscsi_add_hdr(ctask, sizeof(*hdr));
 158         if (rc)
 159                 return rc;
 160         hdr->opcode = ISCSI_OP_SCSI_CMD;
 161         hdr->flags = ISCSI_ATTR_SIMPLE;
 162         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
 163         hdr->itt = build_itt(ctask->itt, conn->id, session->age);
 164         hdr->data_length = cpu_to_be32(scsi_bufflen(sc));
 165         hdr->cmdsn = cpu_to_be32(session->cmdsn);
 166         session->cmdsn++;
 167         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 168         memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
 169         if (sc->cmd_len < MAX_COMMAND_SIZE)
 170                 memset(&hdr->cdb[sc->cmd_len], 0,
 171                         MAX_COMMAND_SIZE - sc->cmd_len);
 172
 173         ctask->imm_count = 0;
 174         if (sc->sc_data_direction == DMA_TO_DEVICE) {
 175                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 176                 /*
 177                  * Write counters:
 178                  *
 179                  *      imm_count       bytes to be sent right after
 180                  *                      SCSI PDU Header
 181                  *
 182                  *      unsol_count     bytes(as Data-Out) to be sent
 183                  *                      without R2T ack right after
 184                  *                      immediate data
 185                  *
 186                  *      r2t_data_count  bytes to be sent via R2T ack's
 187                  *
 188                  *      pad_count       bytes to be sent as zero-padding
 189                  */
 190                 ctask->unsol_count = 0;
 191                 ctask->unsol_offset = 0;
 192                 ctask->unsol_datasn = 0;
 193
 194                 if (session->imm_data_en) {
 195                         if (scsi_bufflen(sc) >= session->first_burst)
 196                                 ctask->imm_count = min(session->first_burst,
 197                                                         conn->max_xmit_dlength);
 198                         else
 199                                 ctask->imm_count = min(scsi_bufflen(sc),
 200                                                         conn->max_xmit_dlength);
 201                         hton24(hdr->dlength, ctask->imm_count);
 202                 } else
 203                         zero_data(hdr->dlength);
 204
 205                 if (!session->initial_r2t_en) {
 206                         ctask->unsol_count = min((session->first_burst),
 207                                 (scsi_bufflen(sc))) - ctask->imm_count;
 208                         ctask->unsol_offset = ctask->imm_count;
 209                 }
 210
 211                 if (!ctask->unsol_count)
 212                         /* No unsolicit Data-Out's */
 213                         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 214         } else {
 215                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 216                 zero_data(hdr->dlength);
 217
 218                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
 219                         hdr->flags |= ISCSI_FLAG_CMD_READ;
 220         }
 221
 222         /* calculate size of additional header segments (AHSs) */
 223         hdrlength = ctask->hdr_len - sizeof(*hdr);
 224
 225         WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
 226         hdrlength /= ISCSI_PAD_LEN;
 227
 228         WARN_ON(hdrlength >= 256);
 229         hdr->hlength = hdrlength & 0xFF;
 230
 231         if (conn->session->tt->init_cmd_task(conn->ctask))
 232                 return EIO;
 233
 234         conn->scsicmd_pdus_cnt++;
 235         debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x len %d "
 236                 "cmdsn %d win %d]\n",
 237                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 238                 conn->id, sc, sc->cmnd[0], ctask->itt, scsi_bufflen(sc),
 239                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 240         return 0;
 241 }
 242
 243 /**
 244  * iscsi_complete_command - return command back to scsi-ml
 245  * @ctask: iscsi cmd task
 246  *
 247  * Must be called with session lock.
 248  * This function returns the scsi command to scsi-ml and returns
 249  * the cmd task to the pool of available cmd tasks.
 250  */
 251 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
 252 {
 253         struct iscsi_conn *conn = ctask->conn;
 254         struct iscsi_session *session = conn->session;
 255         struct scsi_cmnd *sc = ctask->sc;
 256
 257         ctask->state = ISCSI_TASK_COMPLETED;
 258         ctask->sc = NULL;
 259         /* SCSI eh reuses commands to verify us */
 260         sc->SCp.ptr = NULL;
 261         if (conn->ctask == ctask)
 262                 conn->ctask = NULL;
 263         list_del_init(&ctask->running);
 264         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
 265         sc->scsi_done(sc);
 266 }
 267
 268 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
 269 {
 270         atomic_inc(&ctask->refcount);
 271 }
 272
 273 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
 274 {
 275         if (atomic_dec_and_test(&ctask->refcount))
 276                 iscsi_complete_command(ctask);
 277 }
 278
 279 /*
 280  * session lock must be held
 281  */
 282 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
 283                          int err)
 284 {
 285         struct scsi_cmnd *sc;
 286
 287         sc = ctask->sc;
 288         if (!sc)
 289                 return;
 290
 291         if (ctask->state == ISCSI_TASK_PENDING)
 292                 /*
 293                  * cmd never made it to the xmit thread, so we should not count
 294                  * the cmd in the sequencing
 295                  */
 296                 conn->session->queued_cmdsn--;
 297         else
 298                 conn->session->tt->cleanup_cmd_task(conn, ctask);
 299
 300         sc->result = err;
 301         scsi_set_resid(sc, scsi_bufflen(sc));
 302         if (conn->ctask == ctask)
 303                 conn->ctask = NULL;
 304         /* release ref from queuecommand */
 305         __iscsi_put_ctask(ctask);
 306 }
 307
 308 /**
 309  * iscsi_free_mgmt_task - return mgmt task back to pool
 310  * @conn: iscsi connection
 311  * @mtask: mtask
 312  *
 313  * Must be called with session lock.
 314  */
 315 void iscsi_free_mgmt_task(struct iscsi_conn *conn,
 316                           struct iscsi_mgmt_task *mtask)
 317 {
 318         list_del_init(&mtask->running);
 319         if (conn->login_mtask == mtask)
 320                 return;
 321
 322         if (conn->ping_mtask == mtask)
 323                 conn->ping_mtask = NULL;
 324         __kfifo_put(conn->session->mgmtpool.queue,
 325                     (void*)&mtask, sizeof(void*));
 326 }
 327 EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
 328
 329 static struct iscsi_mgmt_task *
 330 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 331                       char *data, uint32_t data_size)
 332 {
 333         struct iscsi_session *session = conn->session;
 334         struct iscsi_mgmt_task *mtask;
 335
 336         if (session->state == ISCSI_STATE_TERMINATE)
 337                 return NULL;
 338
 339         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 340             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 341                 /*
 342                  * Login and Text are sent serially, in
 343                  * request-followed-by-response sequence.
 344                  * Same mtask can be used. Same ITT must be used.
 345                  * Note that login_mtask is preallocated at conn_create().
 346                  */
 347                 mtask = conn->login_mtask;
 348         else {
 349                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 350                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 351
 352                 if (!__kfifo_get(session->mgmtpool.queue,
 353                                  (void*)&mtask, sizeof(void*)))
 354                         return NULL;
 355         }
 356
 357         if (data_size) {
 358                 memcpy(mtask->data, data, data_size);
 359                 mtask->data_count = data_size;
 360         } else
 361                 mtask->data_count = 0;
 362
 363         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 364         INIT_LIST_HEAD(&mtask->running);
 365         list_add_tail(&mtask->running, &conn->mgmtqueue);
 366         return mtask;
 367 }
 368
 369 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 370                         char *data, uint32_t data_size)
 371 {
 372         struct iscsi_conn *conn = cls_conn->dd_data;
 373         struct iscsi_session *session = conn->session;
 374         int err = 0;
 375
 376         spin_lock_bh(&session->lock);
 377         if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
 378                 err = -EPERM;
 379         spin_unlock_bh(&session->lock);
 380         scsi_queue_work(session->host, &conn->xmitwork);
 381         return err;
 382 }
 383 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 384
 385 /**
 386  * iscsi_cmd_rsp - SCSI Command Response processing
 387  * @conn: iscsi connection
 388  * @hdr: iscsi header
 389  * @ctask: scsi command task
 390  * @data: cmd data buffer
 391  * @datalen: len of buffer
 392  *
 393  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 394  * then completes the command and task.
 395  **/
 396 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 397                                struct iscsi_cmd_task *ctask, char *data,
 398                                int datalen)
 399 {
 400         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
 401         struct iscsi_session *session = conn->session;
 402         struct scsi_cmnd *sc = ctask->sc;
 403
 404         iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
 405         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 406
 407         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 408
 409         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 410                 sc->result = DID_ERROR << 16;
 411                 goto out;
 412         }
 413
 414         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 415                 uint16_t senselen;
 416
 417                 if (datalen < 2) {
 418 invalid_datalen:
 419                         iscsi_conn_printk(KERN_ERR,  conn,
 420                                          "Got CHECK_CONDITION but invalid data "
 421                                          "buffer size of %d\n", datalen);
 422                         sc->result = DID_BAD_TARGET << 16;
 423                         goto out;
 424                 }
 425
 426                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
 427                 if (datalen < senselen)
 428                         goto invalid_datalen;
 429
 430                 memcpy(sc->sense_buffer, data + 2,
 431                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 432                 debug_scsi("copied %d bytes of sense\n",
 433                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 434         }
 435
 436         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 437                            ISCSI_FLAG_CMD_OVERFLOW)) {
 438                 int res_count = be32_to_cpu(rhdr->residual_count);
 439
 440                 if (res_count > 0 &&
 441                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 442                      res_count <= scsi_bufflen(sc)))
 443                         scsi_set_resid(sc, res_count);
 444                 else
 445                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 446         } else if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
 447                                   ISCSI_FLAG_CMD_BIDI_OVERFLOW))
 448                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 449
 450 out:
 451         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 452                    (long)sc, sc->result, ctask->itt);
 453         conn->scsirsp_pdus_cnt++;
 454
 455         __iscsi_put_ctask(ctask);
 456 }
 457
 458 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 459 {
 460         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 461
 462         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 463         conn->tmfrsp_pdus_cnt++;
 464
 465         if (conn->tmf_state != TMF_QUEUED)
 466                 return;
 467
 468         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 469                 conn->tmf_state = TMF_SUCCESS;
 470         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 471                 conn->tmf_state = TMF_NOT_FOUND;
 472         else
 473                 conn->tmf_state = TMF_FAILED;
 474         wake_up(&conn->ehwait);
 475 }
 476
 477 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 478 {
 479         struct iscsi_nopout hdr;
 480         struct iscsi_mgmt_task *mtask;
 481
 482         if (!rhdr && conn->ping_mtask)
 483                 return;
 484
 485         memset(&hdr, 0, sizeof(struct iscsi_nopout));
 486         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
 487         hdr.flags = ISCSI_FLAG_CMD_FINAL;
 488
 489         if (rhdr) {
 490                 memcpy(hdr.lun, rhdr->lun, 8);
 491                 hdr.ttt = rhdr->ttt;
 492                 hdr.itt = RESERVED_ITT;
 493         } else
 494                 hdr.ttt = RESERVED_ITT;
 495
 496         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
 497         if (!mtask) {
 498                 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
 499                 return;
 500         }
 501
 502         /* only track our nops */
 503         if (!rhdr) {
 504                 conn->ping_mtask = mtask;
 505                 conn->last_ping = jiffies;
 506         }
 507         scsi_queue_work(conn->session->host, &conn->xmitwork);
 508 }
 509
 510 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 511                                char *data, int datalen)
 512 {
 513         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
 514         struct iscsi_hdr rejected_pdu;
 515         uint32_t itt;
 516
 517         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
 518
 519         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
 520                 if (ntoh24(reject->dlength) > datalen)
 521                         return ISCSI_ERR_PROTO;
 522
 523                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
 524                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
 525                         itt = get_itt(rejected_pdu.itt);
 526                         iscsi_conn_printk(KERN_ERR, conn,
 527                                           "itt 0x%x had pdu (op 0x%x) rejected "
 528                                           "due to DataDigest error.\n", itt,
 529                                           rejected_pdu.opcode);
 530                 }
 531         }
 532         return 0;
 533 }
 534
 535 /**
 536  * __iscsi_complete_pdu - complete pdu
 537  * @conn: iscsi conn
 538  * @hdr: iscsi header
 539  * @data: data buffer
 540  * @datalen: len of data buffer
 541  *
 542  * Completes pdu processing by freeing any resources allocated at
 543  * queuecommand or send generic. session lock must be held and verify
 544  * itt must have been called.
 545  */
 546 static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 547                                 char *data, int datalen)
 548 {
 549         struct iscsi_session *session = conn->session;
 550         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
 551         struct iscsi_cmd_task *ctask;
 552         struct iscsi_mgmt_task *mtask;
 553         uint32_t itt;
 554
 555         conn->last_recv = jiffies;
 556         if (hdr->itt != RESERVED_ITT)
 557                 itt = get_itt(hdr->itt);
 558         else
 559                 itt = ~0U;
 560
 561         if (itt < session->cmds_max) {
 562                 ctask = session->cmds[itt];
 563
 564                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 565                            opcode, conn->id, ctask->itt, datalen);
 566
 567                 switch(opcode) {
 568                 case ISCSI_OP_SCSI_CMD_RSP:
 569                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 570                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 571                                            datalen);
 572                         break;
 573                 case ISCSI_OP_SCSI_DATA_IN:
 574                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 575                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 576                                 conn->scsirsp_pdus_cnt++;
 577                                 __iscsi_put_ctask(ctask);
 578                         }
 579                         break;
 580                 case ISCSI_OP_R2T:
 581                         /* LLD handles this for now */
 582                         break;
 583                 default:
 584                         rc = ISCSI_ERR_BAD_OPCODE;
 585                         break;
 586                 }
 587         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 588                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 589                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 590
 591                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 592                            opcode, conn->id, mtask->itt, datalen);
 593
 594                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 595                 switch(opcode) {
 596                 case ISCSI_OP_LOGOUT_RSP:
 597                         if (datalen) {
 598                                 rc = ISCSI_ERR_PROTO;
 599                                 break;
 600                         }
 601                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 602                         /* fall through */
 603                 case ISCSI_OP_LOGIN_RSP:
 604                 case ISCSI_OP_TEXT_RSP:
 605                         /*
 606                          * login related PDU's exp_statsn is handled in
 607                          * userspace
 608                          */
 609                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 610                                 rc = ISCSI_ERR_CONN_FAILED;
 611                         iscsi_free_mgmt_task(conn, mtask);
 612                         break;
 613                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 614                         if (datalen) {
 615                                 rc = ISCSI_ERR_PROTO;
 616                                 break;
 617                         }
 618
 619                         iscsi_tmf_rsp(conn, hdr);
 620                         iscsi_free_mgmt_task(conn, mtask);
 621                         break;
 622                 case ISCSI_OP_NOOP_IN:
 623                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
 624                             datalen) {
 625                                 rc = ISCSI_ERR_PROTO;
 626                                 break;
 627                         }
 628                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 629
 630                         if (conn->ping_mtask != mtask) {
 631                                 /*
 632                                  * If this is not in response to one of our
 633                                  * nops then it must be from userspace.
 634                                  */
 635                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
 636                                                    datalen))
 637                                         rc = ISCSI_ERR_CONN_FAILED;
 638                         }
 639                         iscsi_free_mgmt_task(conn, mtask);
 640                         break;
 641                 default:
 642                         rc = ISCSI_ERR_BAD_OPCODE;
 643                         break;
 644                 }
 645         } else if (itt == ~0U) {
 646                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 647
 648                 switch(opcode) {
 649                 case ISCSI_OP_NOOP_IN:
 650                         if (datalen) {
 651                                 rc = ISCSI_ERR_PROTO;
 652                                 break;
 653                         }
 654
 655                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
 656                                 break;
 657
 658                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
 659                         break;
 660                 case ISCSI_OP_REJECT:
 661                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
 662                         break;
 663                 case ISCSI_OP_ASYNC_EVENT:
 664                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 665                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 666                                 rc = ISCSI_ERR_CONN_FAILED;
 667                         break;
 668                 default:
 669                         rc = ISCSI_ERR_BAD_OPCODE;
 670                         break;
 671                 }
 672         } else
 673                 rc = ISCSI_ERR_BAD_ITT;
 674
 675         return rc;
 676 }
 677
 678 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 679                        char *data, int datalen)
 680 {
 681         int rc;
 682
 683         spin_lock(&conn->session->lock);
 684         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 685         spin_unlock(&conn->session->lock);
 686         return rc;
 687 }
 688 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 689
 690 /* verify itt (itt encoding: age+cid+itt) */
 691 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 692                      uint32_t *ret_itt)
 693 {
 694         struct iscsi_session *session = conn->session;
 695         struct iscsi_cmd_task *ctask;
 696         uint32_t itt;
 697
 698         if (hdr->itt != RESERVED_ITT) {
 699                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
 700                     (session->age << ISCSI_AGE_SHIFT)) {
 701                         iscsi_conn_printk(KERN_ERR, conn,
 702                                           "received itt %x expected session "
 703                                           "age (%x)\n", (__force u32)hdr->itt,
 704                                           session->age & ISCSI_AGE_MASK);
 705                         return ISCSI_ERR_BAD_ITT;
 706                 }
 707
 708                 if (((__force u32)hdr->itt & ISCSI_CID_MASK) !=
 709                     (conn->id << ISCSI_CID_SHIFT)) {
 710                         iscsi_conn_printk(KERN_ERR, conn,
 711                                           "iscsi: received itt %x, expected "
 712                                           "CID (%x)\n",
 713                                           (__force u32)hdr->itt, conn->id);
 714                         return ISCSI_ERR_BAD_ITT;
 715                 }
 716                 itt = get_itt(hdr->itt);
 717         } else
 718                 itt = ~0U;
 719
 720         if (itt < session->cmds_max) {
 721                 ctask = session->cmds[itt];
 722
 723                 if (!ctask->sc) {
 724                         iscsi_conn_printk(KERN_INFO, conn, "dropping ctask "
 725                                           "with itt 0x%x\n", ctask->itt);
 726                         /* force drop */
 727                         return ISCSI_ERR_NO_SCSI_CMD;
 728                 }
 729
 730                 if (ctask->sc->SCp.phase != session->age) {
 731                         iscsi_conn_printk(KERN_ERR, conn,
 732                                           "iscsi: ctask's session age %d, "
 733                                           "expected %d\n", ctask->sc->SCp.phase,
 734                                           session->age);
 735                         return ISCSI_ERR_SESSION_FAILED;
 736                 }
 737         }
 738
 739         *ret_itt = itt;
 740         return 0;
 741 }
 742 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 743
 744 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 745 {
 746         struct iscsi_session *session = conn->session;
 747         unsigned long flags;
 748
 749         spin_lock_irqsave(&session->lock, flags);
 750         if (session->state == ISCSI_STATE_FAILED) {
 751                 spin_unlock_irqrestore(&session->lock, flags);
 752                 return;
 753         }
 754
 755         if (conn->stop_stage == 0)
 756                 session->state = ISCSI_STATE_FAILED;
 757         spin_unlock_irqrestore(&session->lock, flags);
 758         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 759         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 760         iscsi_conn_error(conn->cls_conn, err);
 761 }
 762 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 763
 764 static void iscsi_prep_mtask(struct iscsi_conn *conn,
 765                              struct iscsi_mgmt_task *mtask)
 766 {
 767         struct iscsi_session *session = conn->session;
 768         struct iscsi_hdr *hdr = mtask->hdr;
 769         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 770
 771         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
 772             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 773                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 774         /*
 775          * pre-format CmdSN for outgoing PDU.
 776          */
 777         nop->cmdsn = cpu_to_be32(session->cmdsn);
 778         if (hdr->itt != RESERVED_ITT) {
 779                 hdr->itt = build_itt(mtask->itt, conn->id, session->age);
 780                 /*
 781                  * TODO: We always use immediate, so we never hit this.
 782                  * If we start to send tmfs or nops as non-immediate then
 783                  * we should start checking the cmdsn numbers for mgmt tasks.
 784                  */
 785                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 786                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 787                         session->queued_cmdsn++;
 788                         session->cmdsn++;
 789                 }
 790         }
 791
 792         if (session->tt->init_mgmt_task)
 793                 session->tt->init_mgmt_task(conn, mtask);
 794
 795         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 796                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
 797                    mtask->data_count);
 798 }
 799
 800 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
 801 {
 802         struct iscsi_hdr *hdr = conn->mtask->hdr;
 803         int rc;
 804
 805         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 806                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
 807         spin_unlock_bh(&conn->session->lock);
 808
 809         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
 810         spin_lock_bh(&conn->session->lock);
 811         if (rc)
 812                 return rc;
 813
 814         /* done with this in-progress mtask */
 815         conn->mtask = NULL;
 816         return 0;
 817 }
 818
 819 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
 820 {
 821         struct iscsi_session *session = conn->session;
 822
 823         /*
 824          * Check for iSCSI window and take care of CmdSN wrap-around
 825          */
 826         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
 827                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
 828                            "CmdSN %u/%u\n", session->exp_cmdsn,
 829                            session->max_cmdsn, session->cmdsn,
 830                            session->queued_cmdsn);
 831                 return -ENOSPC;
 832         }
 833         return 0;
 834 }
 835
 836 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
 837 {
 838         struct iscsi_cmd_task *ctask = conn->ctask;
 839         int rc;
 840
 841         __iscsi_get_ctask(ctask);
 842         spin_unlock_bh(&conn->session->lock);
 843         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
 844         spin_lock_bh(&conn->session->lock);
 845         __iscsi_put_ctask(ctask);
 846         if (!rc)
 847                 /* done with this ctask */
 848                 conn->ctask = NULL;
 849         return rc;
 850 }
 851
 852 /**
 853  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
 854  * @ctask: ctask to requeue
 855  *
 856  * LLDs that need to run a ctask from the session workqueue should call
 857  * this. The session lock must be held.
 858  */
 859 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
 860 {
 861         struct iscsi_conn *conn = ctask->conn;
 862
 863         list_move_tail(&ctask->running, &conn->requeue);
 864         scsi_queue_work(conn->session->host, &conn->xmitwork);
 865 }
 866 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
 867
 868 /**
 869  * iscsi_data_xmit - xmit any command into the scheduled connection
 870  * @conn: iscsi connection
 871  *
 872  * Notes:
 873  *      The function can return -EAGAIN in which case the caller must
 874  *      re-schedule it again later or recover. '0' return code means
 875  *      successful xmit.
 876  **/
 877 static int iscsi_data_xmit(struct iscsi_conn *conn)
 878 {
 879         int rc = 0;
 880
 881         spin_lock_bh(&conn->session->lock);
 882         if (unlikely(conn->suspend_tx)) {
 883                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 884                 spin_unlock_bh(&conn->session->lock);
 885                 return -ENODATA;
 886         }
 887
 888         if (conn->ctask) {
 889                 rc = iscsi_xmit_ctask(conn);
 890                 if (rc)
 891                         goto again;
 892         }
 893
 894         if (conn->mtask) {
 895                 rc = iscsi_xmit_mtask(conn);
 896                 if (rc)
 897                         goto again;
 898         }
 899
 900         /*
 901          * process mgmt pdus like nops before commands since we should
 902          * only have one nop-out as a ping from us and targets should not
 903          * overflow us with nop-ins
 904          */
 905 check_mgmt:
 906         while (!list_empty(&conn->mgmtqueue)) {
 907                 conn->mtask = list_entry(conn->mgmtqueue.next,
 908                                          struct iscsi_mgmt_task, running);
 909                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 910                         iscsi_free_mgmt_task(conn, conn->mtask);
 911                         conn->mtask = NULL;
 912                         continue;
 913                 }
 914
 915                 iscsi_prep_mtask(conn, conn->mtask);
 916                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
 917                 rc = iscsi_xmit_mtask(conn);
 918                 if (rc)
 919                         goto again;
 920         }
 921
 922         /* process pending command queue */
 923         while (!list_empty(&conn->xmitqueue)) {
 924                 if (conn->tmf_state == TMF_QUEUED)
 925                         break;
 926
 927                 conn->ctask = list_entry(conn->xmitqueue.next,
 928                                          struct iscsi_cmd_task, running);
 929                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 930                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
 931                         continue;
 932                 }
 933                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
 934                         fail_command(conn, conn->ctask, DID_ABORT << 16);
 935                         continue;
 936                 }
 937
 938                 conn->ctask->state = ISCSI_TASK_RUNNING;
 939                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
 940                 rc = iscsi_xmit_ctask(conn);
 941                 if (rc)
 942                         goto again;
 943                 /*
 944                  * we could continuously get new ctask requests so
 945                  * we need to check the mgmt queue for nops that need to
 946                  * be sent to aviod starvation
 947                  */
 948                 if (!list_empty(&conn->mgmtqueue))
 949                         goto check_mgmt;
 950         }
 951
 952         while (!list_empty(&conn->requeue)) {
 953                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
 954                         break;
 955
 956                 /*
 957                  * we always do fastlogout - conn stop code will clean up.
 958                  */
 959                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
 960                         break;
 961
 962                 conn->ctask = list_entry(conn->requeue.next,
 963                                          struct iscsi_cmd_task, running);
 964                 conn->ctask->state = ISCSI_TASK_RUNNING;
 965                 list_move_tail(conn->requeue.next, &conn->run_list);
 966                 rc = iscsi_xmit_ctask(conn);
 967                 if (rc)
 968                         goto again;
 969                 if (!list_empty(&conn->mgmtqueue))
 970                         goto check_mgmt;
 971         }
 972         spin_unlock_bh(&conn->session->lock);
 973         return -ENODATA;
 974
 975 again:
 976         if (unlikely(conn->suspend_tx))
 977                 rc = -ENODATA;
 978         spin_unlock_bh(&conn->session->lock);
 979         return rc;
 980 }
 981
 982 static void iscsi_xmitworker(struct work_struct *work)
 983 {
 984         struct iscsi_conn *conn =
 985                 container_of(work, struct iscsi_conn, xmitwork);
 986         int rc;
 987         /*
 988          * serialize Xmit worker on a per-connection basis.
 989          */
 990         do {
 991                 rc = iscsi_data_xmit(conn);
 992         } while (rc >= 0 || rc == -EAGAIN);
 993 }
 994
 995 enum {
 996         FAILURE_BAD_HOST = 1,
 997         FAILURE_SESSION_FAILED,
 998         FAILURE_SESSION_FREED,
 999         FAILURE_WINDOW_CLOSED,
1000         FAILURE_OOM,
1001         FAILURE_SESSION_TERMINATE,
1002         FAILURE_SESSION_IN_RECOVERY,
1003         FAILURE_SESSION_RECOVERY_TIMEOUT,
1004         FAILURE_SESSION_LOGGING_OUT,
1005         FAILURE_SESSION_NOT_READY,
1006 };
1007
1008 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1009 {
1010         struct Scsi_Host *host;
1011         int reason = 0;
1012         struct iscsi_session *session;
1013         struct iscsi_conn *conn;
1014         struct iscsi_cmd_task *ctask = NULL;
1015
1016         sc->scsi_done = done;
1017         sc->result = 0;
1018         sc->SCp.ptr = NULL;
1019
1020         host = sc->device->host;
1021         spin_unlock(host->host_lock);
1022
1023         session = iscsi_hostdata(host->hostdata);
1024         spin_lock(&session->lock);
1025
1026         reason = iscsi_session_chkready(session_to_cls(session));
1027         if (reason) {
1028                 sc->result = reason;
1029                 goto fault;
1030         }
1031
1032         /*
1033          * ISCSI_STATE_FAILED is a temp. state. The recovery
1034          * code will decide what is best to do with command queued
1035          * during this time
1036          */
1037         if (session->state != ISCSI_STATE_LOGGED_IN &&
1038             session->state != ISCSI_STATE_FAILED) {
1039                 /*
1040                  * to handle the race between when we set the recovery state
1041                  * and block the session we requeue here (commands could
1042                  * be entering our queuecommand while a block is starting
1043                  * up because the block code is not locked)
1044                  */
1045                 switch (session->state) {
1046                 case ISCSI_STATE_IN_RECOVERY:
1047                         reason = FAILURE_SESSION_IN_RECOVERY;
1048                         sc->result = DID_IMM_RETRY << 16;
1049                         break;
1050                 case ISCSI_STATE_LOGGING_OUT:
1051                         reason = FAILURE_SESSION_LOGGING_OUT;
1052                         sc->result = DID_IMM_RETRY << 16;
1053                         break;
1054                 case ISCSI_STATE_RECOVERY_FAILED:
1055                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1056                         sc->result = DID_NO_CONNECT << 16;
1057                         break;
1058                 case ISCSI_STATE_TERMINATE:
1059                         reason = FAILURE_SESSION_TERMINATE;
1060                         sc->result = DID_NO_CONNECT << 16;
1061                         break;
1062                 default:
1063                         reason = FAILURE_SESSION_FREED;
1064                         sc->result = DID_NO_CONNECT << 16;
1065                 }
1066                 goto fault;
1067         }
1068
1069         conn = session->leadconn;
1070         if (!conn) {
1071                 reason = FAILURE_SESSION_FREED;
1072                 sc->result = DID_NO_CONNECT << 16;
1073                 goto fault;
1074         }
1075
1076         if (iscsi_check_cmdsn_window_closed(conn)) {
1077                 reason = FAILURE_WINDOW_CLOSED;
1078                 goto reject;
1079         }
1080
1081         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1082                          sizeof(void*))) {
1083                 reason = FAILURE_OOM;
1084                 goto reject;
1085         }
1086         session->queued_cmdsn++;
1087
1088         sc->SCp.phase = session->age;
1089         sc->SCp.ptr = (char *)ctask;
1090
1091         atomic_set(&ctask->refcount, 1);
1092         ctask->state = ISCSI_TASK_PENDING;
1093         ctask->conn = conn;
1094         ctask->sc = sc;
1095         INIT_LIST_HEAD(&ctask->running);
1096
1097         list_add_tail(&ctask->running, &conn->xmitqueue);
1098         spin_unlock(&session->lock);
1099
1100         scsi_queue_work(host, &conn->xmitwork);
1101         spin_lock(host->host_lock);
1102         return 0;
1103
1104 reject:
1105         spin_unlock(&session->lock);
1106         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1107         spin_lock(host->host_lock);
1108         return SCSI_MLQUEUE_HOST_BUSY;
1109
1110 fault:
1111         spin_unlock(&session->lock);
1112         debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1113         scsi_set_resid(sc, scsi_bufflen(sc));
1114         sc->scsi_done(sc);
1115         spin_lock(host->host_lock);
1116         return 0;
1117 }
1118 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1119
1120 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1121 {
1122         if (depth > ISCSI_MAX_CMD_PER_LUN)
1123                 depth = ISCSI_MAX_CMD_PER_LUN;
1124         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1125         return sdev->queue_depth;
1126 }
1127 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1128
1129 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1130 {
1131         struct iscsi_session *session = class_to_transport_session(cls_session);
1132
1133         spin_lock_bh(&session->lock);
1134         if (session->state != ISCSI_STATE_LOGGED_IN) {
1135                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1136                 if (session->leadconn)
1137                         wake_up(&session->leadconn->ehwait);
1138         }
1139         spin_unlock_bh(&session->lock);
1140 }
1141 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1142
1143 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1144 {
1145         struct Scsi_Host *host = sc->device->host;
1146         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1147         struct iscsi_conn *conn = session->leadconn;
1148
1149         mutex_lock(&session->eh_mutex);
1150         spin_lock_bh(&session->lock);
1151         if (session->state == ISCSI_STATE_TERMINATE) {
1152 failed:
1153                 debug_scsi("failing host reset: session terminated "
1154                            "[CID %d age %d]\n", conn->id, session->age);
1155                 spin_unlock_bh(&session->lock);
1156                 mutex_unlock(&session->eh_mutex);
1157                 return FAILED;
1158         }
1159
1160         spin_unlock_bh(&session->lock);
1161         mutex_unlock(&session->eh_mutex);
1162         /*
1163          * we drop the lock here but the leadconn cannot be destoyed while
1164          * we are in the scsi eh
1165          */
1166         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1167
1168         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
1169         wait_event_interruptible(conn->ehwait,
1170                                  session->state == ISCSI_STATE_TERMINATE ||
1171                                  session->state == ISCSI_STATE_LOGGED_IN ||
1172                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1173         if (signal_pending(current))
1174                 flush_signals(current);
1175
1176         mutex_lock(&session->eh_mutex);
1177         spin_lock_bh(&session->lock);
1178         if (session->state == ISCSI_STATE_LOGGED_IN)
1179                 iscsi_session_printk(KERN_INFO, session,
1180                                      "host reset succeeded\n");
1181         else
1182                 goto failed;
1183         spin_unlock_bh(&session->lock);
1184         mutex_unlock(&session->eh_mutex);
1185         return SUCCESS;
1186 }
1187 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1188
1189 static void iscsi_tmf_timedout(unsigned long data)
1190 {
1191         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1192         struct iscsi_session *session = conn->session;
1193
1194         spin_lock(&session->lock);
1195         if (conn->tmf_state == TMF_QUEUED) {
1196                 conn->tmf_state = TMF_TIMEDOUT;
1197                 debug_scsi("tmf timedout\n");
1198                 /* unblock eh_abort() */
1199                 wake_up(&conn->ehwait);
1200         }
1201         spin_unlock(&session->lock);
1202 }
1203
1204 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1205                                    struct iscsi_tm *hdr, int age,
1206                                    int timeout)
1207 {
1208         struct iscsi_session *session = conn->session;
1209         struct iscsi_mgmt_task *mtask;
1210
1211         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1212                                       NULL, 0);
1213         if (!mtask) {
1214                 spin_unlock_bh(&session->lock);
1215                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1216                 spin_lock_bh(&session->lock);
1217                 debug_scsi("tmf exec failure\n");
1218                 return -EPERM;
1219         }
1220         conn->tmfcmd_pdus_cnt++;
1221         conn->tmf_timer.expires = timeout * HZ + jiffies;
1222         conn->tmf_timer.function = iscsi_tmf_timedout;
1223         conn->tmf_timer.data = (unsigned long)conn;
1224         add_timer(&conn->tmf_timer);
1225         debug_scsi("tmf set timeout\n");
1226
1227         spin_unlock_bh(&session->lock);
1228         mutex_unlock(&session->eh_mutex);
1229         scsi_queue_work(session->host, &conn->xmitwork);
1230
1231         /*
1232          * block eh thread until:
1233          *
1234          * 1) tmf response
1235          * 2) tmf timeout
1236          * 3) session is terminated or restarted or userspace has
1237          * given up on recovery
1238          */
1239         wait_event_interruptible(conn->ehwait, age != session->age ||
1240                                  session->state != ISCSI_STATE_LOGGED_IN ||
1241                                  conn->tmf_state != TMF_QUEUED);
1242         if (signal_pending(current))
1243                 flush_signals(current);
1244         del_timer_sync(&conn->tmf_timer);
1245
1246         mutex_lock(&session->eh_mutex);
1247         spin_lock_bh(&session->lock);
1248         /* if the session drops it will clean up the mtask */
1249         if (age != session->age ||
1250             session->state != ISCSI_STATE_LOGGED_IN)
1251                 return -ENOTCONN;
1252         return 0;
1253 }
1254
1255 /*
1256  * Fail commands. session lock held and recv side suspended and xmit
1257  * thread flushed
1258  */
1259 static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
1260                               int error)
1261 {
1262         struct iscsi_cmd_task *ctask, *tmp;
1263
1264         if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
1265                 conn->ctask = NULL;
1266
1267         /* flush pending */
1268         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1269                 if (lun == ctask->sc->device->lun || lun == -1) {
1270                         debug_scsi("failing pending sc %p itt 0x%x\n",
1271                                    ctask->sc, ctask->itt);
1272                         fail_command(conn, ctask, error << 16);
1273                 }
1274         }
1275
1276         list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
1277                 if (lun == ctask->sc->device->lun || lun == -1) {
1278                         debug_scsi("failing requeued sc %p itt 0x%x\n",
1279                                    ctask->sc, ctask->itt);
1280                         fail_command(conn, ctask, error << 16);
1281                 }
1282         }
1283
1284         /* fail all other running */
1285         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1286                 if (lun == ctask->sc->device->lun || lun == -1) {
1287                         debug_scsi("failing in progress sc %p itt 0x%x\n",
1288                                    ctask->sc, ctask->itt);
1289                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1290                 }
1291         }
1292 }
1293
1294 static void iscsi_suspend_tx(struct iscsi_conn *conn)
1295 {
1296         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1297         scsi_flush_work(conn->session->host);
1298 }
1299
1300 static void iscsi_start_tx(struct iscsi_conn *conn)
1301 {
1302         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1303         scsi_queue_work(conn->session->host, &conn->xmitwork);
1304 }
1305
1306 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1307 {
1308         struct iscsi_cls_session *cls_session;
1309         struct iscsi_session *session;
1310         struct iscsi_conn *conn;
1311         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1312
1313         cls_session = starget_to_session(scsi_target(scmd->device));
1314         session = class_to_transport_session(cls_session);
1315
1316         debug_scsi("scsi cmd %p timedout\n", scmd);
1317
1318         spin_lock(&session->lock);
1319         if (session->state != ISCSI_STATE_LOGGED_IN) {
1320                 /*
1321                  * We are probably in the middle of iscsi recovery so let
1322                  * that complete and handle the error.
1323                  */
1324                 rc = EH_RESET_TIMER;
1325                 goto done;
1326         }
1327
1328         conn = session->leadconn;
1329         if (!conn) {
1330                 /* In the middle of shuting down */
1331                 rc = EH_RESET_TIMER;
1332                 goto done;
1333         }
1334
1335         if (!conn->recv_timeout && !conn->ping_timeout)
1336                 goto done;
1337         /*
1338          * if the ping timedout then we are in the middle of cleaning up
1339          * and can let the iscsi eh handle it
1340          */
1341         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1342                             (conn->ping_timeout * HZ), jiffies))
1343                 rc = EH_RESET_TIMER;
1344         /*
1345          * if we are about to check the transport then give the command
1346          * more time
1347          */
1348         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1349                            jiffies))
1350                 rc = EH_RESET_TIMER;
1351         /* if in the middle of checking the transport then give us more time */
1352         if (conn->ping_mtask)
1353                 rc = EH_RESET_TIMER;
1354 done:
1355         spin_unlock(&session->lock);
1356         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1357         return rc;
1358 }
1359
1360 static void iscsi_check_transport_timeouts(unsigned long data)
1361 {
1362         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1363         struct iscsi_session *session = conn->session;
1364         unsigned long timeout, next_timeout = 0, last_recv;
1365
1366         spin_lock(&session->lock);
1367         if (session->state != ISCSI_STATE_LOGGED_IN)
1368                 goto done;
1369
1370         timeout = conn->recv_timeout;
1371         if (!timeout)
1372                 goto done;
1373
1374         timeout *= HZ;
1375         last_recv = conn->last_recv;
1376         if (time_before_eq(last_recv + timeout + (conn->ping_timeout * HZ),
1377                            jiffies)) {
1378                 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
1379                                   "expired, last rx %lu, last ping %lu, "
1380                                   "now %lu\n", conn->ping_timeout, last_recv,
1381                                   conn->last_ping, jiffies);
1382                 spin_unlock(&session->lock);
1383                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1384                 return;
1385         }
1386
1387         if (time_before_eq(last_recv + timeout, jiffies)) {
1388                 if (time_before_eq(conn->last_ping, last_recv)) {
1389                         /* send a ping to try to provoke some traffic */
1390                         debug_scsi("Sending nopout as ping on conn %p\n", conn);
1391                         iscsi_send_nopout(conn, NULL);
1392                 }
1393                 next_timeout = last_recv + timeout + (conn->ping_timeout * HZ);
1394         } else
1395                 next_timeout = last_recv + timeout;
1396
1397         debug_scsi("Setting next tmo %lu\n", next_timeout);
1398         mod_timer(&conn->transport_timer, next_timeout);
1399 done:
1400         spin_unlock(&session->lock);
1401 }
1402
1403 static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
1404                                       struct iscsi_tm *hdr)
1405 {
1406         memset(hdr, 0, sizeof(*hdr));
1407         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1408         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
1409         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1410         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1411         hdr->rtt = ctask->hdr->itt;
1412         hdr->refcmdsn = ctask->hdr->cmdsn;
1413 }
1414
1415 int iscsi_eh_abort(struct scsi_cmnd *sc)
1416 {
1417         struct Scsi_Host *host = sc->device->host;
1418         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1419         struct iscsi_conn *conn;
1420         struct iscsi_cmd_task *ctask;
1421         struct iscsi_tm *hdr;
1422         int rc, age;
1423
1424         mutex_lock(&session->eh_mutex);
1425         spin_lock_bh(&session->lock);
1426         /*
1427          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1428          * got the command.
1429          */
1430         if (!sc->SCp.ptr) {
1431                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1432                 spin_unlock_bh(&session->lock);
1433                 mutex_unlock(&session->eh_mutex);
1434                 return SUCCESS;
1435         }
1436
1437         /*
1438          * If we are not logged in or we have started a new session
1439          * then let the host reset code handle this
1440          */
1441         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1442             sc->SCp.phase != session->age) {
1443                 spin_unlock_bh(&session->lock);
1444                 mutex_unlock(&session->eh_mutex);
1445                 return FAILED;
1446         }
1447
1448         conn = session->leadconn;
1449         conn->eh_abort_cnt++;
1450         age = session->age;
1451
1452         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1453         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1454
1455         /* ctask completed before time out */
1456         if (!ctask->sc) {
1457                 debug_scsi("sc completed while abort in progress\n");
1458                 goto success;
1459         }
1460
1461         if (ctask->state == ISCSI_TASK_PENDING) {
1462                 fail_command(conn, ctask, DID_ABORT << 16);
1463                 goto success;
1464         }
1465
1466         /* only have one tmf outstanding at a time */
1467         if (conn->tmf_state != TMF_INITIAL)
1468                 goto failed;
1469         conn->tmf_state = TMF_QUEUED;
1470
1471         hdr = &conn->tmhdr;
1472         iscsi_prep_abort_task_pdu(ctask, hdr);
1473
1474         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1475                 rc = FAILED;
1476                 goto failed;
1477         }
1478
1479         switch (conn->tmf_state) {
1480         case TMF_SUCCESS:
1481                 spin_unlock_bh(&session->lock);
1482                 iscsi_suspend_tx(conn);
1483                 /*
1484                  * clean up task if aborted. grab the recv lock as a writer
1485                  */
1486                 write_lock_bh(conn->recv_lock);
1487                 spin_lock(&session->lock);
1488                 fail_command(conn, ctask, DID_ABORT << 16);
1489                 conn->tmf_state = TMF_INITIAL;
1490                 spin_unlock(&session->lock);
1491                 write_unlock_bh(conn->recv_lock);
1492                 iscsi_start_tx(conn);
1493                 goto success_unlocked;
1494         case TMF_TIMEDOUT:
1495                 spin_unlock_bh(&session->lock);
1496                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1497                 goto failed_unlocked;
1498         case TMF_NOT_FOUND:
1499                 if (!sc->SCp.ptr) {
1500                         conn->tmf_state = TMF_INITIAL;
1501                         /* ctask completed before tmf abort response */
1502                         debug_scsi("sc completed while abort in progress\n");
1503                         goto success;
1504                 }
1505                 /* fall through */
1506         default:
1507                 conn->tmf_state = TMF_INITIAL;
1508                 goto failed;
1509         }
1510
1511 success:
1512         spin_unlock_bh(&session->lock);
1513 success_unlocked:
1514         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1515         mutex_unlock(&session->eh_mutex);
1516         return SUCCESS;
1517
1518 failed:
1519         spin_unlock_bh(&session->lock);
1520 failed_unlocked:
1521         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1522                     ctask ? ctask->itt : 0);
1523         mutex_unlock(&session->eh_mutex);
1524         return FAILED;
1525 }
1526 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1527
1528 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1529 {
1530         memset(hdr, 0, sizeof(*hdr));
1531         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1532         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1533         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1534         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1535         hdr->rtt = RESERVED_ITT;
1536 }
1537
1538 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1539 {
1540         struct Scsi_Host *host = sc->device->host;
1541         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1542         struct iscsi_conn *conn;
1543         struct iscsi_tm *hdr;
1544         int rc = FAILED;
1545
1546         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1547
1548         mutex_lock(&session->eh_mutex);
1549         spin_lock_bh(&session->lock);
1550         /*
1551          * Just check if we are not logged in. We cannot check for
1552          * the phase because the reset could come from a ioctl.
1553          */
1554         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1555                 goto unlock;
1556         conn = session->leadconn;
1557
1558         /* only have one tmf outstanding at a time */
1559         if (conn->tmf_state != TMF_INITIAL)
1560                 goto unlock;
1561         conn->tmf_state = TMF_QUEUED;
1562
1563         hdr = &conn->tmhdr;
1564         iscsi_prep_lun_reset_pdu(sc, hdr);
1565
1566         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1567                                     session->lu_reset_timeout)) {
1568                 rc = FAILED;
1569                 goto unlock;
1570         }
1571
1572         switch (conn->tmf_state) {
1573         case TMF_SUCCESS:
1574                 break;
1575         case TMF_TIMEDOUT:
1576                 spin_unlock_bh(&session->lock);
1577                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1578                 goto done;
1579         default:
1580                 conn->tmf_state = TMF_INITIAL;
1581                 goto unlock;
1582         }
1583
1584         rc = SUCCESS;
1585         spin_unlock_bh(&session->lock);
1586
1587         iscsi_suspend_tx(conn);
1588         /* need to grab the recv lock then session lock */
1589         write_lock_bh(conn->recv_lock);
1590         spin_lock(&session->lock);
1591         fail_all_commands(conn, sc->device->lun, DID_ERROR);
1592         conn->tmf_state = TMF_INITIAL;
1593         spin_unlock(&session->lock);
1594         write_unlock_bh(conn->recv_lock);
1595
1596         iscsi_start_tx(conn);
1597         goto done;
1598
1599 unlock:
1600         spin_unlock_bh(&session->lock);
1601 done:
1602         debug_scsi("iscsi_eh_device_reset %s\n",
1603                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1604         mutex_unlock(&session->eh_mutex);
1605         return rc;
1606 }
1607 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1608
1609 /*
1610  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1611  * should be accessed via kfifo_{get,put} on q->queue.
1612  * Optionally, the caller can obtain the array of object pointers
1613  * by passing in a non-NULL @items pointer
1614  */
1615 int
1616 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1617 {
1618         int i, num_arrays = 1;
1619
1620         memset(q, 0, sizeof(*q));
1621
1622         q->max = max;
1623
1624         /* If the user passed an items pointer, he wants a copy of
1625          * the array. */
1626         if (items)
1627                 num_arrays++;
1628         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1629         if (q->pool == NULL)
1630                 goto enomem;
1631
1632         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1633                               GFP_KERNEL, NULL);
1634         if (q->queue == ERR_PTR(-ENOMEM))
1635                 goto enomem;
1636
1637         for (i = 0; i < max; i++) {
1638                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1639                 if (q->pool[i] == NULL) {
1640                         q->max = i;
1641                         goto enomem;
1642                 }
1643                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1644         }
1645
1646         if (items) {
1647                 *items = q->pool + max;
1648                 memcpy(*items, q->pool, max * sizeof(void *));
1649         }
1650
1651         return 0;
1652
1653 enomem:
1654         iscsi_pool_free(q);
1655         return -ENOMEM;
1656 }
1657 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1658
1659 void iscsi_pool_free(struct iscsi_pool *q)
1660 {
1661         int i;
1662
1663         for (i = 0; i < q->max; i++)
1664                 kfree(q->pool[i]);
1665         if (q->pool)
1666                 kfree(q->pool);
1667 }
1668 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1669
1670 /*
1671  * iSCSI Session's hostdata organization:
1672  *
1673  *    *------------------* <== hostdata_session(host->hostdata)
1674  *    | ptr to class sess|
1675  *    |------------------| <== iscsi_hostdata(host->hostdata)
1676  *    | iscsi_session    |
1677  *    *------------------*
1678  */
1679
1680 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1681                                  _sz % sizeof(unsigned long))
1682
1683 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1684
1685 /**
1686  * iscsi_session_setup - create iscsi cls session and host and session
1687  * @scsit: scsi transport template
1688  * @iscsit: iscsi transport template
1689  * @cmds_max: scsi host can queue
1690  * @qdepth: scsi host cmds per lun
1691  * @cmd_task_size: LLD ctask private data size
1692  * @mgmt_task_size: LLD mtask private data size
1693  * @initial_cmdsn: initial CmdSN
1694  * @hostno: host no allocated
1695  *
1696  * This can be used by software iscsi_transports that allocate
1697  * a session per scsi host.
1698  **/
1699 struct iscsi_cls_session *
1700 iscsi_session_setup(struct iscsi_transport *iscsit,
1701                     struct scsi_transport_template *scsit,
1702                     uint16_t cmds_max, uint16_t qdepth,
1703                     int cmd_task_size, int mgmt_task_size,
1704                     uint32_t initial_cmdsn, uint32_t *hostno)
1705 {
1706         struct Scsi_Host *shost;
1707         struct iscsi_session *session;
1708         struct iscsi_cls_session *cls_session;
1709         int cmd_i;
1710
1711         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1712                 if (qdepth != 0)
1713                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1714                               "Queue depth must be between 1 and %d.\n",
1715                               qdepth, ISCSI_MAX_CMD_PER_LUN);
1716                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1717         }
1718
1719         if (!is_power_of_2(cmds_max) ||
1720             cmds_max >= ISCSI_MGMT_ITT_OFFSET) {
1721                 if (cmds_max != 0)
1722                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1723                                "can_queue must be a power of 2 and between "
1724                                "2 and %d - setting to %d.\n", cmds_max,
1725                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1726                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1727         }
1728
1729         shost = scsi_host_alloc(iscsit->host_template,
1730                                 hostdata_privsize(sizeof(*session)));
1731         if (!shost)
1732                 return NULL;
1733
1734         /* the iscsi layer takes one task for reserve */
1735         shost->can_queue = cmds_max - 1;
1736         shost->cmd_per_lun = qdepth;
1737         shost->max_id = 1;
1738         shost->max_channel = 0;
1739         shost->max_lun = iscsit->max_lun;
1740         shost->max_cmd_len = iscsit->max_cmd_len;
1741         shost->transportt = scsit;
1742         shost->transportt->create_work_queue = 1;
1743         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1744         *hostno = shost->host_no;
1745
1746         session = iscsi_hostdata(shost->hostdata);
1747         memset(session, 0, sizeof(struct iscsi_session));
1748         session->host = shost;
1749         session->state = ISCSI_STATE_FREE;
1750         session->fast_abort = 1;
1751         session->lu_reset_timeout = 15;
1752         session->abort_timeout = 10;
1753         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1754         session->cmds_max = cmds_max;
1755         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1756         session->exp_cmdsn = initial_cmdsn + 1;
1757         session->max_cmdsn = initial_cmdsn + 1;
1758         session->max_r2t = 1;
1759         session->tt = iscsit;
1760         mutex_init(&session->eh_mutex);
1761
1762         /* initialize SCSI PDU commands pool */
1763         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1764                             (void***)&session->cmds,
1765                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1766                 goto cmdpool_alloc_fail;
1767
1768         /* pre-format cmds pool with ITT */
1769         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1770                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1771
1772                 if (cmd_task_size)
1773                         ctask->dd_data = &ctask[1];
1774                 ctask->itt = cmd_i;
1775                 INIT_LIST_HEAD(&ctask->running);
1776         }
1777
1778         spin_lock_init(&session->lock);
1779
1780         /* initialize immediate command pool */
1781         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1782                            (void***)&session->mgmt_cmds,
1783                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1784                 goto mgmtpool_alloc_fail;
1785
1786
1787         /* pre-format immediate cmds pool with ITT */
1788         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1789                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1790
1791                 if (mgmt_task_size)
1792                         mtask->dd_data = &mtask[1];
1793                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1794                 INIT_LIST_HEAD(&mtask->running);
1795         }
1796
1797         if (scsi_add_host(shost, NULL))
1798                 goto add_host_fail;
1799
1800         if (!try_module_get(iscsit->owner))
1801                 goto cls_session_fail;
1802
1803         cls_session = iscsi_create_session(shost, iscsit, 0);
1804         if (!cls_session)
1805                 goto module_put;
1806         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1807
1808         return cls_session;
1809
1810 module_put:
1811         module_put(iscsit->owner);
1812 cls_session_fail:
1813         scsi_remove_host(shost);
1814 add_host_fail:
1815         iscsi_pool_free(&session->mgmtpool);
1816 mgmtpool_alloc_fail:
1817         iscsi_pool_free(&session->cmdpool);
1818 cmdpool_alloc_fail:
1819         scsi_host_put(shost);
1820         return NULL;
1821 }
1822 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1823
1824 /**
1825  * iscsi_session_teardown - destroy session, host, and cls_session
1826  * shost: scsi host
1827  *
1828  * This can be used by software iscsi_transports that allocate
1829  * a session per scsi host.
1830  **/
1831 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1832 {
1833         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1834         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1835         struct module *owner = cls_session->transport->owner;
1836
1837         iscsi_remove_session(cls_session);
1838         scsi_remove_host(shost);
1839
1840         iscsi_pool_free(&session->mgmtpool);
1841         iscsi_pool_free(&session->cmdpool);
1842
1843         kfree(session->password);
1844         kfree(session->password_in);
1845         kfree(session->username);
1846         kfree(session->username_in);
1847         kfree(session->targetname);
1848         kfree(session->netdev);
1849         kfree(session->hwaddress);
1850         kfree(session->initiatorname);
1851
1852         iscsi_free_session(cls_session);
1853         scsi_host_put(shost);
1854         module_put(owner);
1855 }
1856 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1857
1858 /**
1859  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1860  * @cls_session: iscsi_cls_session
1861  * @conn_idx: cid
1862  **/
1863 struct iscsi_cls_conn *
1864 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1865 {
1866         struct iscsi_session *session = class_to_transport_session(cls_session);
1867         struct iscsi_conn *conn;
1868         struct iscsi_cls_conn *cls_conn;
1869         char *data;
1870
1871         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1872         if (!cls_conn)
1873                 return NULL;
1874         conn = cls_conn->dd_data;
1875         memset(conn, 0, sizeof(*conn));
1876
1877         conn->session = session;
1878         conn->cls_conn = cls_conn;
1879         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1880         conn->id = conn_idx;
1881         conn->exp_statsn = 0;
1882         conn->tmf_state = TMF_INITIAL;
1883
1884         init_timer(&conn->transport_timer);
1885         conn->transport_timer.data = (unsigned long)conn;
1886         conn->transport_timer.function = iscsi_check_transport_timeouts;
1887
1888         INIT_LIST_HEAD(&conn->run_list);
1889         INIT_LIST_HEAD(&conn->mgmt_run_list);
1890         INIT_LIST_HEAD(&conn->mgmtqueue);
1891         INIT_LIST_HEAD(&conn->xmitqueue);
1892         INIT_LIST_HEAD(&conn->requeue);
1893         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
1894
1895         /* allocate login_mtask used for the login/text sequences */
1896         spin_lock_bh(&session->lock);
1897         if (!__kfifo_get(session->mgmtpool.queue,
1898                          (void*)&conn->login_mtask,
1899                          sizeof(void*))) {
1900                 spin_unlock_bh(&session->lock);
1901                 goto login_mtask_alloc_fail;
1902         }
1903         spin_unlock_bh(&session->lock);
1904
1905         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
1906         if (!data)
1907                 goto login_mtask_data_alloc_fail;
1908         conn->login_mtask->data = conn->data = data;
1909
1910         init_timer(&conn->tmf_timer);
1911         init_waitqueue_head(&conn->ehwait);
1912
1913         return cls_conn;
1914
1915 login_mtask_data_alloc_fail:
1916         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1917                     sizeof(void*));
1918 login_mtask_alloc_fail:
1919         iscsi_destroy_conn(cls_conn);
1920         return NULL;
1921 }
1922 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1923
1924 /**
1925  * iscsi_conn_teardown - teardown iscsi connection
1926  * cls_conn: iscsi class connection
1927  *
1928  * TODO: we may need to make this into a two step process
1929  * like scsi-mls remove + put host
1930  */
1931 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1932 {
1933         struct iscsi_conn *conn = cls_conn->dd_data;
1934         struct iscsi_session *session = conn->session;
1935         unsigned long flags;
1936
1937         del_timer_sync(&conn->transport_timer);
1938
1939         spin_lock_bh(&session->lock);
1940         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1941         if (session->leadconn == conn) {
1942                 /*
1943                  * leading connection? then give up on recovery.
1944                  */
1945                 session->state = ISCSI_STATE_TERMINATE;
1946                 wake_up(&conn->ehwait);
1947         }
1948         spin_unlock_bh(&session->lock);
1949
1950         /*
1951          * Block until all in-progress commands for this connection
1952          * time out or fail.
1953          */
1954         for (;;) {
1955                 spin_lock_irqsave(session->host->host_lock, flags);
1956                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1957                         spin_unlock_irqrestore(session->host->host_lock, flags);
1958                         break;
1959                 }
1960                 spin_unlock_irqrestore(session->host->host_lock, flags);
1961                 msleep_interruptible(500);
1962                 iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
1963                                   "host_busy %d host_failed %d\n",
1964                                   session->host->host_busy,
1965                                   session->host->host_failed);
1966                 /*
1967                  * force eh_abort() to unblock
1968                  */
1969                 wake_up(&conn->ehwait);
1970         }
1971
1972         /* flush queued up work because we free the connection below */
1973         iscsi_suspend_tx(conn);
1974
1975         spin_lock_bh(&session->lock);
1976         kfree(conn->data);
1977         kfree(conn->persistent_address);
1978         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1979                     sizeof(void*));
1980         if (session->leadconn == conn)
1981                 session->leadconn = NULL;
1982         spin_unlock_bh(&session->lock);
1983
1984         iscsi_destroy_conn(cls_conn);
1985 }
1986 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1987
1988 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1989 {
1990         struct iscsi_conn *conn = cls_conn->dd_data;
1991         struct iscsi_session *session = conn->session;
1992
1993         if (!session) {
1994                 iscsi_conn_printk(KERN_ERR, conn,
1995                                   "can't start unbound connection\n");
1996                 return -EPERM;
1997         }
1998
1999         if ((session->imm_data_en || !session->initial_r2t_en) &&
2000              session->first_burst > session->max_burst) {
2001                 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
2002                                   "first_burst %d max_burst %d\n",
2003                                   session->first_burst, session->max_burst);
2004                 return -EINVAL;
2005         }
2006
2007         if (conn->ping_timeout && !conn->recv_timeout) {
2008                 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
2009                                   "zero. Using 5 seconds\n.");
2010                 conn->recv_timeout = 5;
2011         }
2012
2013         if (conn->recv_timeout && !conn->ping_timeout) {
2014                 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
2015                                   "zero. Using 5 seconds.\n");
2016                 conn->ping_timeout = 5;
2017         }
2018
2019         spin_lock_bh(&session->lock);
2020         conn->c_stage = ISCSI_CONN_STARTED;
2021         session->state = ISCSI_STATE_LOGGED_IN;
2022         session->queued_cmdsn = session->cmdsn;
2023
2024         conn->last_recv = jiffies;
2025         conn->last_ping = jiffies;
2026         if (conn->recv_timeout && conn->ping_timeout)
2027                 mod_timer(&conn->transport_timer,
2028                           jiffies + (conn->recv_timeout * HZ));
2029
2030         switch(conn->stop_stage) {
2031         case STOP_CONN_RECOVER:
2032                 /*
2033                  * unblock eh_abort() if it is blocked. re-try all
2034                  * commands after successful recovery
2035                  */
2036                 conn->stop_stage = 0;
2037                 conn->tmf_state = TMF_INITIAL;
2038                 session->age++;
2039                 break;
2040         case STOP_CONN_TERM:
2041                 conn->stop_stage = 0;
2042                 break;
2043         default:
2044                 break;
2045         }
2046         spin_unlock_bh(&session->lock);
2047
2048         iscsi_unblock_session(session_to_cls(session));
2049         wake_up(&conn->ehwait);
2050         return 0;
2051 }
2052 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2053
2054 static void
2055 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2056 {
2057         struct iscsi_mgmt_task *mtask, *tmp;
2058
2059         /* handle pending */
2060         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2061                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2062                 iscsi_free_mgmt_task(conn, mtask);
2063         }
2064
2065         /* handle running */
2066         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2067                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2068                 iscsi_free_mgmt_task(conn, mtask);
2069         }
2070
2071         conn->mtask = NULL;
2072 }
2073
2074 static void iscsi_start_session_recovery(struct iscsi_session *session,
2075                                          struct iscsi_conn *conn, int flag)
2076 {
2077         int old_stop_stage;
2078
2079         del_timer_sync(&conn->transport_timer);
2080
2081         mutex_lock(&session->eh_mutex);
2082         spin_lock_bh(&session->lock);
2083         if (conn->stop_stage == STOP_CONN_TERM) {
2084                 spin_unlock_bh(&session->lock);
2085                 mutex_unlock(&session->eh_mutex);
2086                 return;
2087         }
2088
2089         /*
2090          * The LLD either freed/unset the lock on us, or userspace called
2091          * stop but did not create a proper connection (connection was never
2092          * bound or it was unbound then stop was called).
2093          */
2094         if (!conn->recv_lock) {
2095                 spin_unlock_bh(&session->lock);
2096                 mutex_unlock(&session->eh_mutex);
2097                 return;
2098         }
2099
2100         /*
2101          * When this is called for the in_login state, we only want to clean
2102          * up the login task and connection. We do not need to block and set
2103          * the recovery state again
2104          */
2105         if (flag == STOP_CONN_TERM)
2106                 session->state = ISCSI_STATE_TERMINATE;
2107         else if (conn->stop_stage != STOP_CONN_RECOVER)
2108                 session->state = ISCSI_STATE_IN_RECOVERY;
2109
2110         old_stop_stage = conn->stop_stage;
2111         conn->stop_stage = flag;
2112         conn->c_stage = ISCSI_CONN_STOPPED;
2113         spin_unlock_bh(&session->lock);
2114
2115         iscsi_suspend_tx(conn);
2116
2117         write_lock_bh(conn->recv_lock);
2118         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2119         write_unlock_bh(conn->recv_lock);
2120
2121         /*
2122          * for connection level recovery we should not calculate
2123          * header digest. conn->hdr_size used for optimization
2124          * in hdr_extract() and will be re-negotiated at
2125          * set_param() time.
2126          */
2127         if (flag == STOP_CONN_RECOVER) {
2128                 conn->hdrdgst_en = 0;
2129                 conn->datadgst_en = 0;
2130                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2131                     old_stop_stage != STOP_CONN_RECOVER) {
2132                         debug_scsi("blocking session\n");
2133                         iscsi_block_session(session_to_cls(session));
2134                 }
2135         }
2136
2137         /*
2138          * flush queues.
2139          */
2140         spin_lock_bh(&session->lock);
2141         fail_all_commands(conn, -1,
2142                         STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR);
2143         flush_control_queues(session, conn);
2144         spin_unlock_bh(&session->lock);
2145         mutex_unlock(&session->eh_mutex);
2146 }
2147
2148 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2149 {
2150         struct iscsi_conn *conn = cls_conn->dd_data;
2151         struct iscsi_session *session = conn->session;
2152
2153         switch (flag) {
2154         case STOP_CONN_RECOVER:
2155         case STOP_CONN_TERM:
2156                 iscsi_start_session_recovery(session, conn, flag);
2157                 break;
2158         default:
2159                 iscsi_conn_printk(KERN_ERR, conn,
2160                                   "invalid stop flag %d\n", flag);
2161         }
2162 }
2163 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2164
2165 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2166                     struct iscsi_cls_conn *cls_conn, int is_leading)
2167 {
2168         struct iscsi_session *session = class_to_transport_session(cls_session);
2169         struct iscsi_conn *conn = cls_conn->dd_data;
2170
2171         spin_lock_bh(&session->lock);
2172         if (is_leading)
2173                 session->leadconn = conn;
2174         spin_unlock_bh(&session->lock);
2175
2176         /*
2177          * Unblock xmitworker(), Login Phase will pass through.
2178          */
2179         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2180         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2181         return 0;
2182 }
2183 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2184
2185
2186 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2187                     enum iscsi_param param, char *buf, int buflen)
2188 {
2189         struct iscsi_conn *conn = cls_conn->dd_data;
2190         struct iscsi_session *session = conn->session;
2191         uint32_t value;
2192
2193         switch(param) {
2194         case ISCSI_PARAM_FAST_ABORT:
2195                 sscanf(buf, "%d", &session->fast_abort);
2196                 break;
2197         case ISCSI_PARAM_ABORT_TMO:
2198                 sscanf(buf, "%d", &session->abort_timeout);
2199                 break;
2200         case ISCSI_PARAM_LU_RESET_TMO:
2201                 sscanf(buf, "%d", &session->lu_reset_timeout);
2202                 break;
2203         case ISCSI_PARAM_PING_TMO:
2204                 sscanf(buf, "%d", &conn->ping_timeout);
2205                 break;
2206         case ISCSI_PARAM_RECV_TMO:
2207                 sscanf(buf, "%d", &conn->recv_timeout);
2208                 break;
2209         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2210                 sscanf(buf, "%d", &conn->max_recv_dlength);
2211                 break;
2212         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2213                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2214                 break;
2215         case ISCSI_PARAM_HDRDGST_EN:
2216                 sscanf(buf, "%d", &conn->hdrdgst_en);
2217                 break;
2218         case ISCSI_PARAM_DATADGST_EN:
2219                 sscanf(buf, "%d", &conn->datadgst_en);
2220                 break;
2221         case ISCSI_PARAM_INITIAL_R2T_EN:
2222                 sscanf(buf, "%d", &session->initial_r2t_en);
2223                 break;
2224         case ISCSI_PARAM_MAX_R2T:
2225                 sscanf(buf, "%d", &session->max_r2t);
2226                 break;
2227         case ISCSI_PARAM_IMM_DATA_EN:
2228                 sscanf(buf, "%d", &session->imm_data_en);
2229                 break;
2230         case ISCSI_PARAM_FIRST_BURST:
2231                 sscanf(buf, "%d", &session->first_burst);
2232                 break;
2233         case ISCSI_PARAM_MAX_BURST:
2234                 sscanf(buf, "%d", &session->max_burst);
2235                 break;
2236         case ISCSI_PARAM_PDU_INORDER_EN:
2237                 sscanf(buf, "%d", &session->pdu_inorder_en);
2238                 break;
2239         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2240                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2241                 break;
2242         case ISCSI_PARAM_ERL:
2243                 sscanf(buf, "%d", &session->erl);
2244                 break;
2245         case ISCSI_PARAM_IFMARKER_EN:
2246                 sscanf(buf, "%d", &value);
2247                 BUG_ON(value);
2248                 break;
2249         case ISCSI_PARAM_OFMARKER_EN:
2250                 sscanf(buf, "%d", &value);
2251                 BUG_ON(value);
2252                 break;
2253         case ISCSI_PARAM_EXP_STATSN:
2254                 sscanf(buf, "%u", &conn->exp_statsn);
2255                 break;
2256         case ISCSI_PARAM_USERNAME:
2257                 kfree(session->username);
2258                 session->username = kstrdup(buf, GFP_KERNEL);
2259                 if (!session->username)
2260                         return -ENOMEM;
2261                 break;
2262         case ISCSI_PARAM_USERNAME_IN:
2263                 kfree(session->username_in);
2264                 session->username_in = kstrdup(buf, GFP_KERNEL);
2265                 if (!session->username_in)
2266                         return -ENOMEM;
2267                 break;
2268         case ISCSI_PARAM_PASSWORD:
2269                 kfree(session->password);
2270                 session->password = kstrdup(buf, GFP_KERNEL);
2271                 if (!session->password)
2272                         return -ENOMEM;
2273                 break;
2274         case ISCSI_PARAM_PASSWORD_IN:
2275                 kfree(session->password_in);
2276                 session->password_in = kstrdup(buf, GFP_KERNEL);
2277                 if (!session->password_in)
2278                         return -ENOMEM;
2279                 break;
2280         case ISCSI_PARAM_TARGET_NAME:
2281                 /* this should not change between logins */
2282                 if (session->targetname)
2283                         break;
2284
2285                 session->targetname = kstrdup(buf, GFP_KERNEL);
2286                 if (!session->targetname)
2287                         return -ENOMEM;
2288                 break;
2289         case ISCSI_PARAM_TPGT:
2290                 sscanf(buf, "%d", &session->tpgt);
2291                 break;
2292         case ISCSI_PARAM_PERSISTENT_PORT:
2293                 sscanf(buf, "%d", &conn->persistent_port);
2294                 break;
2295         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2296                 /*
2297                  * this is the address returned in discovery so it should
2298                  * not change between logins.
2299                  */
2300                 if (conn->persistent_address)
2301                         break;
2302
2303                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2304                 if (!conn->persistent_address)
2305                         return -ENOMEM;
2306                 break;
2307         default:
2308                 return -ENOSYS;
2309         }
2310
2311         return 0;
2312 }
2313 EXPORT_SYMBOL_GPL(iscsi_set_param);
2314
2315 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2316                             enum iscsi_param param, char *buf)
2317 {
2318         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
2319         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2320         int len;
2321
2322         switch(param) {
2323         case ISCSI_PARAM_FAST_ABORT:
2324                 len = sprintf(buf, "%d\n", session->fast_abort);
2325                 break;
2326         case ISCSI_PARAM_ABORT_TMO:
2327                 len = sprintf(buf, "%d\n", session->abort_timeout);
2328                 break;
2329         case ISCSI_PARAM_LU_RESET_TMO:
2330                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2331                 break;
2332         case ISCSI_PARAM_INITIAL_R2T_EN:
2333                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2334                 break;
2335         case ISCSI_PARAM_MAX_R2T:
2336                 len = sprintf(buf, "%hu\n", session->max_r2t);
2337                 break;
2338         case ISCSI_PARAM_IMM_DATA_EN:
2339                 len = sprintf(buf, "%d\n", session->imm_data_en);
2340                 break;
2341         case ISCSI_PARAM_FIRST_BURST:
2342                 len = sprintf(buf, "%u\n", session->first_burst);
2343                 break;
2344         case ISCSI_PARAM_MAX_BURST:
2345                 len = sprintf(buf, "%u\n", session->max_burst);
2346                 break;
2347         case ISCSI_PARAM_PDU_INORDER_EN:
2348                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2349                 break;
2350         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2351                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2352                 break;
2353         case ISCSI_PARAM_ERL:
2354                 len = sprintf(buf, "%d\n", session->erl);
2355                 break;
2356         case ISCSI_PARAM_TARGET_NAME:
2357                 len = sprintf(buf, "%s\n", session->targetname);
2358                 break;
2359         case ISCSI_PARAM_TPGT:
2360                 len = sprintf(buf, "%d\n", session->tpgt);
2361                 break;
2362         case ISCSI_PARAM_USERNAME:
2363                 len = sprintf(buf, "%s\n", session->username);
2364                 break;
2365         case ISCSI_PARAM_USERNAME_IN:
2366                 len = sprintf(buf, "%s\n", session->username_in);
2367                 break;
2368         case ISCSI_PARAM_PASSWORD:
2369                 len = sprintf(buf, "%s\n", session->password);
2370                 break;
2371         case ISCSI_PARAM_PASSWORD_IN:
2372                 len = sprintf(buf, "%s\n", session->password_in);
2373                 break;
2374         default:
2375                 return -ENOSYS;
2376         }
2377
2378         return len;
2379 }
2380 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2381
2382 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2383                          enum iscsi_param param, char *buf)
2384 {
2385         struct iscsi_conn *conn = cls_conn->dd_data;
2386         int len;
2387
2388         switch(param) {
2389         case ISCSI_PARAM_PING_TMO:
2390                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2391                 break;
2392         case ISCSI_PARAM_RECV_TMO:
2393                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2394                 break;
2395         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2396                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2397                 break;
2398         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2399                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2400                 break;
2401         case ISCSI_PARAM_HDRDGST_EN:
2402                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2403                 break;
2404         case ISCSI_PARAM_DATADGST_EN:
2405                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2406                 break;
2407         case ISCSI_PARAM_IFMARKER_EN:
2408                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2409                 break;
2410         case ISCSI_PARAM_OFMARKER_EN:
2411                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2412                 break;
2413         case ISCSI_PARAM_EXP_STATSN:
2414                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2415                 break;
2416         case ISCSI_PARAM_PERSISTENT_PORT:
2417                 len = sprintf(buf, "%d\n", conn->persistent_port);
2418                 break;
2419         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2420                 len = sprintf(buf, "%s\n", conn->persistent_address);
2421                 break;
2422         default:
2423                 return -ENOSYS;
2424         }
2425
2426         return len;
2427 }
2428 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2429
2430 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2431                          char *buf)
2432 {
2433         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2434         int len;
2435
2436         switch (param) {
2437         case ISCSI_HOST_PARAM_NETDEV_NAME:
2438                 if (!session->netdev)
2439                         len = sprintf(buf, "%s\n", "default");
2440                 else
2441                         len = sprintf(buf, "%s\n", session->netdev);
2442                 break;
2443         case ISCSI_HOST_PARAM_HWADDRESS:
2444                 if (!session->hwaddress)
2445                         len = sprintf(buf, "%s\n", "default");
2446                 else
2447                         len = sprintf(buf, "%s\n", session->hwaddress);
2448                 break;
2449         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2450                 if (!session->initiatorname)
2451                         len = sprintf(buf, "%s\n", "unknown");
2452                 else
2453                         len = sprintf(buf, "%s\n", session->initiatorname);
2454                 break;
2455
2456         default:
2457                 return -ENOSYS;
2458         }
2459
2460         return len;
2461 }
2462 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2463
2464 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2465                          char *buf, int buflen)
2466 {
2467         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2468
2469         switch (param) {
2470         case ISCSI_HOST_PARAM_NETDEV_NAME:
2471                 if (!session->netdev)
2472                         session->netdev = kstrdup(buf, GFP_KERNEL);
2473                 break;
2474         case ISCSI_HOST_PARAM_HWADDRESS:
2475                 if (!session->hwaddress)
2476                         session->hwaddress = kstrdup(buf, GFP_KERNEL);
2477                 break;
2478         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2479                 if (!session->initiatorname)
2480                         session->initiatorname = kstrdup(buf, GFP_KERNEL);
2481                 break;
2482         default:
2483                 return -ENOSYS;
2484         }
2485
2486         return 0;
2487 }
2488 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2489
2490 MODULE_AUTHOR("Mike Christie");
2491 MODULE_DESCRIPTION("iSCSI library functions");
2492 MODULE_LICENSE("GPL");